For contact info, please see the Sci.Electronics.Repair FAQ Email Links Page.
Copyright © 1994-2004
All Rights Reserved
Reproduction of this document in whole or in part is permitted if both of the following conditions are satisfied:
1. This notice is included in its entirety at the beginning.
2. There is no charge except to cover the costs of copying.
Note that many of the problems and solutions are listed with respect to specific models. Even though your model and problem may not be included, there is a good chance your problem is covered but with respect to some other model printer or copier. Therefore, search for a generic description of the symptoms and you may get lucky.
Since the operation of laser printers and photocopiers is very similar, check both chapters to see if your problem is covered when dealing with either type equipment.
There is also a chapter on fax machine problems though it is pretty sparse at the moment.
Eventually, this document may be expanded into a full "Notes on the Troubleshooting and Repair of Printers and Photocopiers". For now, be happy that it exists at all! :-)
As always, comments, suggestions, and corrections are welcome.
Portions of this document also appear at PrinterCartridgesInk.com under "Printer Advice". As far as I know, this was done without my permission but since he included the appropriate attribution and copyright notices, I'm not complaining. The formatting may even be a bit better. :)
See the document: Troubleshooting and Repair of Consumer Electronics Equipment for general information on tools, test equipment, tips, techniques, and much more.
While printers are not generally considered dangerous pieces of equipment (compared to TV, monitors, and microwave ovens, at least), some types - laser printers in particular - present a variety of hazards that should not be underestimated. In addition, photocopiers - particularly larger high speed machines - need to be treated with great respect while servicing.
There are minimal dangers in servicing most printers. However, there may be exposed line voltage near the line cord and long hair or neck-ties may be sucked in along with paper! Laser printers have their lasers but these are generally located such that accidental exposure to the beam is minimized. The toner in copiers, plain paper faxes, and laser printers may be harmful if inhaled and is a potential fire/explosion risk if carelessly vacuumed. Each of these possible safety issues is discussed below with additional specific information in the chapters for the equipment to which it applies. All in all, working on printers is relatively low risk.
The first set of items applies to all line operated printers:
The following apply to laser printers and photocopiers:
And finally, for laser printers and laser photocopiers:
Fortunately, under normal conditions, the laser beam will not be turned on unless all interlocks are closed and a page is actually being printed and/or will be in constant motion as a result of the scanning mirror (which reduces the risk considerably). (It is virtually impossible to get to the laser beam before the scanning mirror without total disassembly.) However, certain failure modes could result in a stationary beam which ignores the interlocks so take care whenever working on a laser printer with the covers removed.
For text, an internal character generator (ROM) converts ASCII codes to pin firing patterns. For arbitrary graphics, the actual bit map is read out and used to control the pin drive.
The paper, carriage, and sometimes ribbon movement use stepper motors. These, their drivers, or interconnect cables, are common problem areas.
Instead of pins, these use a wheel with all the possible characters molded on 'leaves' around the perimeter. The wheel spins to the correct character position and a hammer than taps the leaf to impress the character (via a ribbon) on the paper. Carriage and printhead movement is similar to that of dot matrix printers.
(From: Peter (hedgieus@yahoo.com).)
Some history/trivia:
The daisy wheel printer (interestingly) was patented before World War II! It was GE or a GE engineer, but only commercialized by Diablo, which was later bought by Xerox in its expansion to California. Later spinoff was Qume, and then lot of companies got into it, some Japanese, some local (California). Daisy wheel technology was killed by the laser printer becoming cheap and having better quality. Original impetus for it was speed: IBM Selectric was able to print at 10 char/s (good for 110 baud modems!). It moved the whole ball (big inertia). Daisy wheel only moves one spoke, (to print one character) and got 30 chars/s.
Near the end of the era, 'on the fly' printers got as fast as 80 char/sec.
There is a US publication called 'The Hard Copy OBSERVER' from Lyra Research Inc. Tel: (617) 322-0708.
This discusses the latest technologies and who does what. It may not cover the print head technology very much but is a good read if you are into print technology in general.
There are many companies that sell variable print processes. One I have heard of is RALFLATAC. They do a brochure that does an excellent brief of most technologies available for printing. They have UK (and many other sites in europe) and US sites. UK Tel 01732-583661, US Tel (704) 684-3931.
I have no idea if you can easily get copies of either publication from them so here goes a very very brief description.
Ink jet printing has two main types, continuous ink jet (CIJ) and impulse printing (DOD) (drop on demand). Each of these can be a single jet, or an array of jets.
CIJ is a continuous jet of ink cycling round a system and occasionally (when required) a drop is deflected out of the stream onto the paper. The stream is modulated to break it into a consistent drop size. The deflection works like the beam on an oscilloscope. If you charge 1 drop and pass it between two high voltage plates it is deflected. This system also requires cunning mechanics, but the support electronics is much more complex, and probably one of the reasons for its performance limitations being not up to what you might expect. The calculations of the aerodynamics of drops being deflected is no small task, even if look up tables are used.
DOD works in principal like an old Dot Matrix pin printer. Instead of firing a pin at a ribbon, a drop of ink is fired at the paper. The drop is fired by either a piezo crystal squeezing the ink out of a small tube, or by boiling the ink and the vapor forces the ink out of the chamber. The key to both of these processes is in the mechanical design of very small components if 300 dpi is required. The control electronics is a bit cunning, but I figure it is the easy bit.
Priming and cleaning are normally done automatically upon power-on and possibly between pages. However, additional cycles may be needed at times.
With the water based ink, even if the printer is powered off properly which seats the cartridge(s) on a rubber seal, some evaporation occurs so priming will often be needed after it sits idle for a while. Note: Don't kill power to an ink-jet printer as soon as your printout pops free - it needs to position the printhead and cartridge(s) on the rubber boots. Wait until the printhead stops moving and clunking. Some (older) printers don't even have a seal in which case letting it sit idle is even more likely to result in problems.
If there has been ink spilled into the priming area, it may clog up the little hose connecting the priming station to the pump - I have used a wooden toothpick to clear the hole though this may be risky if it should break off. With care, a wire rounded off at the end so as not to puncture the tubing can also be used. Complete disassembly and washing of the parts is probably the best but is probably a pain.
The original ink jet printer of this type was the Teletype Inktronic, which introduced the concept of video-type distortions to printing. It appeared around 1970, and was so bad nobody tried again for years.
(From: Tony Hardman (AHED_CIJ@f54x19.demon.co.uk).)
I guess that is why it was used in industrial applications I guess. Were the 'video-type distortions' a deliberate feature or just a coincidence of how they turned out?
Who are/were Inktronic???(apologies to anyone connected with them) I guess that may have been spin off development from some work contracted out by IBM, but it was so....?? (costly/low res/unreliable - choose one) they lost interest. Although one of the very early machines still runs well on a textile mill. It had a large number of jets side by side, and may be multi color too. I've only seen the patents so don't know exactly what it looks like.
I thought original ink jet printer was a chart recorder developed in the last century. It was just a nozzle on deflection mechanism, and was not modulated so it was always printing. It was a lighter mechanism than actually trying to move a pen and so had some performance advantages over other technology available at the time...
The same reason CIJ still sells world wide, even when high resolution DOD is biting at its heals.
Here are history/trivia. (I used to work at Xerox marking technology group, working on ink-jets and daisy printers.)
Type 1 was commercialized first for printing postal labels and other similar applications. It was a big machine - 5x5x5 meters! Clumsy but fast. This was before laser printers. IBM published detailed (and definitive) research paper on this - circa 1985.
(From: John Eaton (johne@vcd.hp.com).)
The trick is that a lot of the energy that you pump into the resistor leaves the printhead with the fired dot. One way to detect Out_of_Ink is to mount a thermistor on the printhead and watch for a sudden rise in temperature as you are firing.
"I use a HP680C in the office, and it have two cartridges, one for black and one for color (yellow/cian/magenta?). If the printer fire one drop of each ink at a given point, we can have only 6 different colors (ignoring white and black). If it can fire two or more drops at a given point, maybe we can have more colors, but I suspect that the printer use this to control quality of the presentation, not the number of colors. Anybody knows for sure? With dithering it can make more colors, with reduced resolution."
Like most print processes you only have a limited selection of inks to use. Full colour can be derived from three primary colors, just like a monitor. For monitors, these are Red, Green, and Blue because monitors emit light resulting in an additive color process. Inks, on the other hand, absorb light so printing is a subtractive process. The resulting inks should then be cyan (blue+green or -red), magenta (red+blue or -green), and yellow (red+green or -blue).
Therefore, the colors used in common ink-jet printers are not really capable of producing true full spectrum photorealistic quality results since they are red (not magenta), blue (not cyan), and yellow. These are optimized for nice saturated primary colors when used independently. Also see the section: Why are red, blue, and yellow inkjet primaries?.
In addition, the combination of the three primary colors should be capable of being combined to produce black but due to misregistration and the pigments used, this black would be somewhat muddy and brown. Therefore, a separate black ink cartridge is normally used for black printing.
(From: Tony Hardman (AHED_CIJ@f54x19.demon.co.uk).)
With printing there are more problems than solutions and I do not know which method HP use in their printing.
If you can vary the drop size, you can change the drop spread on the paper. This can be done by firing bigger slugs of ink, or multiples of the drop at the same position. As you can figure the ink will either spread and make a bigger drop, or stay the same size and become denser. Depending on the resolution you want these could both improve colour density. This depends on two key components.. The ink, and the paper.
The problems with laying down multiple drops on paper is that if you do a large block the paper will curl up and the overall image becomes worse. This is why you can pay 1$ a sheet for 'quality' paper.
Another problem with this is speed. Firing two drops in the exact same place is difficult... Unless the head is stationary but that is not good either. You may notice that most DOD printers in high resolution mode do a number of passes over the same place. This does allow dithering and other techniques for resolution / colour enhancement. They usually only print while going in one direction for improved mechanical control.
In the 1600 printer there is a heater to assist with the drying times and reduce the curling problem.
Inks are a problem too. They can dry at different times because of the different dyes used, or they may not mix how you expect if you place two colours on top of each other. Its only ink ... but to get the best balance of surface tension, drying time, viscosity, colour, stability.... and more is not as straight forward as it might seam. I have noticed that the water based inks are improving, and there are some that do not run if they get wet (after drying on the paper).
I think the spec in your manual may suggest what method they use.. The printer resolution (best) is 600dpi (I guess), and I recon the best full colour resolution is lower. Also the print head is only 300dpi so you must do two passes to get 600dpi black (single black ink cartridge). This suggests a partial step of 1/600 inch between the passes. What happens when you print black using the colour head? How many passes, how much slower? The resolutions quoted may also be 600 * 300, or what ever. If they make blocks of colour from a potential 600dpi machine, the resultant image is probably only 75dpi (possibly less). This still might be called 600dpi, because the drop placement uses this resolution, but it is not 600dpi at full colour. The resolution of quality picturers / poster is several thousand dpi, but not a variable image (not ink jet).
In the Lyra publications they did publish the real print head specifications for the machines they review. They also include some of the methods of colour printing.
After all this I have noticed that I have not answered the question of how do HP et all get their colour resolutions. All I have mentioned is a few of the parameters that the designers have to deal with.
I don't know the precise answer but it is no doubt a tradeoff between cost and which colors are used most often. For non-photo printing, the straight red, blue, and yellow are far more useful since they can be use by themselves or in simple combination to produce a wide range of vibrant, if not realistic colors. For example, pure red is far more likely to be used for simple graphics than magenta. To make something that looks like pure red using magenta and yellow requires a precise combination - not easy to do with an inkjet printer!
(The following is from someone who also sells inkjet refill kits so this may not be an entirely unbiased writeup.)
(From: John Connolly (toner@idirect.com).)
There are at least 10 ingredients in inkjet ink, starting with triple distilled, de-ionized water, dye or pigment color of a known particle size, humectants such as glycol to minimize evaporation (and head clogging), surfactants to balance the surface tension and paper wetting, resins to get good paper adhesion, biocides and fungicides and buffering agents for the correct pH. These considerations ensure that properly reverse engineered inks not only work, but produce a print comparable to the OEM. For printers like Epson, with fixed permanent print heads in the printer, expensive repairs are also avoided.
To make matters worse HP has rigged their most popular black cartridges for the Deskjet 500 & 600 series to curb refilling, with air bladders, constantly changing maze/ venting assemblies at the bottom, and logic to change the signals to the micro-resistor jets on the 3rd or subsequent reinstallation of the cartridge. The color cartridges for these MUST be refilled before air locks occur, particularly in the yellow chamber.
Some people still manage to get an acceptable refilling success rate with these Deskjets, but we feel it is a bad introduction to refilling for the first time refiller. Deskjet series 700, 800 & 900 are better bets to refill.
But, the current Lexmark, Canon, Xerox and Epson cartridges are by far the easiest to refill.
Image Control's refill kits for the Canon 4000 series refill the BCI-21 black 40 times, or the BCI-21, 12 times EACH color.
More details on inkjet inks, a description of our refill kits which are larger than most offered, references and printer/cartridge tips are available at Image Control's Web Site.
The digital image is generated from a bit map stored in the printer's memory and modulates the laser beam. Scanning is mechanical - a high speed motor spins a multifaceted deflection mirror to get the X-axis and the paper moves to get the Y axis.
LED printers use a large array of LEDs as the image source but are otherwise similar to laser printers.
Plain paper fax machines use similar techniques in their printing mechanism.
Beyond this, copiers and laser printers are nearly identical (at least in principle) except that copiers use a positive process (dark areas in the original result in marks on the paper) and laser printers commonly use a negative process (a spot of light results in a dark mark on the paper).
The most sophisticated machines are now actually scanner-laser printer combinations with buffer memory so that multiple copies can be made without rescanning the original, sorting and collating is more flexible, scaling and rotation can be done digitally, and other features not possible with simple copiers.
(Portions from: Copenhagen Cowboy (cowboy@fastlane.net).)
The photosensitive drum is the heart of the laser printer or copier. In larger machines, it may be a separately replaceable unit. In most laser printers and smaller copiers, it is part of the 'toner cartridge' and is a throw-away (or may be recycled).
The drum is coated with a photosensitive material which has an extremely high resistance when in darkness. It's resistance drops to a low value when illuminated.
All of the following takes place as a continuous process as the drum rotates. Note that the actual photosensitive drum in most copiers and laser printers has a circumference that is much smaller than the length of the printed page. Therefore, only a portion fits at any given time and the charging, exposure, transfer to the paper, cleaning, and erasing is a continuous process:
Where the light hits the drum's surface, its resistance drops dramatically and the charge in these areas is dissipated.
At this point, a swath of the image of your ultimate copied or printed page resides as areas of electrostatic charge on the drum. This is a 'latent' image and must be 'developed'.
Depending on design, the developer material may be separate or actually combined with the toner.
A magnet in the developer unit which is as long as the page is wide causes the developer along with trapped toner to stand out following its lines of force off of its long N-S pole pieces. This forms a kind of brush of toner and developer material which is in contact with the drum as it rotates with its latent image. Normally, the developer material brush is C-shaped, and toner particles are carried in the C-shape (the back of the 'C' is against the drum).
Here is where the developing processes of copiers and laser printers differ:
Below the paper is another corona, the 'transfer corona'. Another high voltage is applied to the back of the paper (once again, around 7 or 8 kV DC) to draw the toner from the drum to the paper. (Remember, all this is going on in a continual cycle and it is all in motion).
That is the basic process. Many variations are possible and depending upon the machine and manufacturer, some of this may be a little different. Where a (disposable) toner cartridge is used, many of these components are replaced with the cartridge - typically the drum, toner itself and developer (usually combined into a single powder), developer magnet (really neat!), cleaning blades, some of the corona wires.
There is also some photocopier information at:
In general the principle of electrostatic laser printing is as follows:
The laser steering engine is combined of the following components:
If you need to scan or to print in high resolution 500 dpi or higher, you end up using a glass F-Theta lens.
(From: David Kuhajda (dkuhajda@locl.net).)
Whatever you do, do NOT use alcohol on an organically based drum, it will ruin it. The alcohol causes the material to crystalize. I use to do copier service and this was stressed a lot by the manufacture as they switched from the old selenium drums to the new opc drums. Direct sunlight will immediately destroy the drum. A couple of minutes under normal lighting is no problem, just place it in a dark area and put a black cloth over the top of the drum while it is out. If you are replacing the drum cleaning blade or cleaning the crud off the blade, make sure you powder up the drum completely and the blade before reapplying power. The toner actually is a slight lubricant and the rubber cleaning blade directly on the drum will also ruin it. Just print a few low text copies after reassembling to allow the blade to reseat properly.
(From: hapticz@email.msn.com.)
Short periods (less than 5 min) under fluorescent lighting is safe.
Direct sunlight kills them immediately.
Just have a clean brown paper bag to shove it into while it sits on the table outside the machine.
Often more damage is done to them physically during insertion/removal. just be careful.
Xerox used to clean the 10" diameter drums with 90% isopropyl alcohol and some kind of "Kim Wipes" in our office, that was years ago though.
Get the book: "Easy Laser Printer Maintenance and Repair by Stephen J. Bigelow".
Your local library should have it or be able to get it. Stephen J. Bigelow has several other books on printer repair, both laser and non laser types. All are very good.
"I just acquired the optics from a dead laser printer and have been trying to understand it. There are two functions I have yet to grasp. One is something which it has but for which I see no need. There seems to be a heater (Contains mica) and a thermometer, with PCB markings like "T1" and H2" or something similar. If these the laser is temperature controlled, why? There seems to be a control photodetector to monitor the laser diode so temperature control appears like overkill unless the photodiode itself has too much temperature dependence and the drum exposure is very critical."
(From: Jonathan M. Elson (jmelson@artsci.wustl.edu).)
There is a heater inside the fuser roller. This is what melts the toner into the paper. It is thermostatically controlled, and then has a safety thermostat in case the control fails.
There are two photodetectors for the laser. One compensates for dimming of the laser over years of use, the other picks up the beam at a particular angle of the polygon mirror, and synchronizes the raster electronics to the polygon rotation.
"The other thing is something I cannot find, the aperture defining the nice well-formed pixel. So far I must admit the study has been a bit superficial but the aperture ought to be pretty obvious if there is one!"
The laser is the aperture. With an optical path of 0.5 m or so, the laser is a pretty good approximation of a true point source. A simple lens makes it look like a very good point source.
"Finally, how are the correction lens made? They look like slices out of the middle of some fair sized lenses, but that would be a very wasteful way to make them. Can they be diamond formed to nearly the final shape and with such good finish so only a simple polish completes them. Grinding the old-fashioned way on a sliver of glass looks doomed to generating all sorts of defective approximations to a sphere. (As far as I can tell they are glass, or some wonderfully hard plastic I would like to know more about!) Can they be molded to sufficient precision? (The sides are ground or sawn.) Thanks to anyone who can bring me up to date on lens fabrication technique."
I think they mold these lenses to near correct shape, then grind and polish to the desired aspheric shape with specialty machines for that purpose. (Note that almost all eyeglasses are aspheric for astigmatism correction.) Yes, these lenses are glass, I've had a few printers apart myself.
There are two basic kinds of toner: magnetic and non-magnetic. If your laser printer has a Cannon 'engine' it most likely uses magnetic. NEVER use the wrong type. The imaging process is extremely delicate and specific toners are important. Use of toner that is slightly different could result in all black or all white copies.
"I have a 3M Model 6312 copier. I believe it is a re-badged Lanier. I didn't pay much for it but it worked well. When the toner warning light came on, I made the mistake of adding the wrong kind of toner. I removed the wrong toner as much as I could by vacuum. Is there anything I should do before adding the right type of toner? Did I do serious damage to the system? What to do if the warning light remained on even with the right type of toner added? Any suggestion will be greatly appreciated."
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
If your copier uses non-magnetic toner, it is mixed with iron powder, called the Developer. Both have to be removed and all residue vacuumed out. If the copier uses magnetic toner, less of it will remain in the machine. Try to get as much as possible out. Do not scratch the roller on which the toner sits.
WARNING: See the section: Warnings about vacuuming laser printer toner before using a household vacuum cleaner to do this!
"I stupidly took apart my Panasonic KX-P1123 to attempt a head swap (the cable was too short!), now that it's back together it just beeps when I try to print. The only things I touched were the rod that the head assembly slides on and the toothed belt also had to come off (I don't think it's a timing belt.. there's no clear markings suggesting that). When I try to print, the head moves to the center, there's no pin action and it starts beeping at two second intervals (and won't stop). It's not the paper sensors because they seem to work properly...any ideas?"
(From: Filip M. Gieszczykiewicz (filipg@repairfaq.org).)
Greetings. A few:
BTW, move the carriage all the way to the right, close the cover and turn it on - does the print head move or does it just sit there and beep?
More depends on the answers and results of the above. BTW, most newer dot-patrix printers just need 2 screws to be removed to release the head. I know the Epson LQ-1050 works like that (and many of that Stars as well). Anyones needs parts from the former? I have one with a dead head (and it's not economical to repair).
"I have a few Epson dot matrix print heads with stuck or sunken pins. Does anyone have experience with disassembling these things for cleaning/repairs? It looks like you just have to pop a few clips to get them apart."
(From: Chris Serrano (brace@loop.com).)
I resurrected one by hanging it pins downs in an ultrasonic cleaner. A lot of old dried up ink floated right out and the stuck pin became obedient again.
(From: Filip M. Gieszczykiewicz (filipg@repairfaq.org).)
Greetings. If one does not have the use of an ultrasonic cleaner, I have found a different way to get these suckers working again.
Go to your local plumbing store and look in the chemicals department for 'CPVC-PVC-ABS CLEANER' (used to clean plastic pipes). This stuff is a combination of groovy chemicals Methyl Ethyl Ketone and Acetone. It will 'melt' most plastics so be sure the print-head's any plastic parts are safely taken off.
Pour some of this stuff into a GLASS container and put the print head, business-end first, in it and leave it there for a few minutes. When the stuff turns dark-purple (all the ink and goo from the print head) you are done. Let it dry (few minutes) and then oil it with LIGHT OIL. Note: Do NOT use WD40 - we're interested with something that sticks around for a few months... WD40 just leaves a 'protective layer' with almost zilch lubricating properties (it's a Water Displacer (WD), after all).
I have done this for a few DataSouth DS-180, Infoscribe 1000s, and Xerox [monster] printers that see a box of 132 column paper a month (each) for a number of years with excellent results. Note: YMMV... these printers have rugged print heads (7/9 pin)... I don't know how a 24-pin Made-in-China feather will respond.
(From: Ralph Wade Phillips (ralphp@gcstation.net).)
What's common in some older Okidata 32x's and 39x's is that the lithium battery *above* the stepper driver will spring a leak, and drop the lithium compound onto the legs of the stepper. I do not know for sure if it's corrosive, conductive, or just plain nasty, but it kills the stepper deader'n'snot.
I'd LOVE to find a replacement - I've got a service customer that has about 2,500(!!!) 320's and 321's in the field, and I am not looking forward to having to exchange all those boards over the next several years.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
I'm going to guess (based on what I've seen in other printers) that there's a set of power transistors (either H-bridge drivers or 1 per coil, depending on the motor) that drive the stepper. These transistors are driven from the printer's microcontroller via an output port - in this case the '273.
Now, if a TTL chips is getting very hot, then either something is drawing too much current from it, or something is overvoltaging one of the pins. A particularly unpleasant failure mode is when a PNP power transistor, with the emitter tied to the V++ rail (the 20V + rail that supplies the motors) decides to short and apply said voltage to the output of whatever device is driving it. If you're unlucky, the next stage is that the output port device breaks down as well, and the CPU data bus gets 20V or more on it. The result is blown chips all over the printer. Please don't ask how I found that out ;-)
My guess is that there's at least one shorted transistor in the stepper motor drive circuit. If the system uses an H-bridge driver (an equal number of NPN and PNP transistors) then if one transistor shorts, its companion is connected across the power rails. When it turns on, the supply is effectively shorted.
I think you'll have to trace out the driver circuit for the stepper motor. Figure out what drives what. Test the transistors, and then replace the defective ones _and_ that '273, which is probably now blown.
"My wife has a "Smith Corona" Model SD800 electronic typewriter that will not advance the ribbon. Everything else seems to work fine. We have been unable to find a local repair for this unit. I think I can fix it with some advice from someone familiar with these machines."
Can you determine if it is a mechanical or electronic problem? For example, with the ribbon removed, does the gear or post that drives it appear to try to turn or not at all?
Modern electronic typewriters are a combination of keyboard, microprocessor, and printer. Therefore, the same sort of troubleshooting approachs can be used as for computer printers.
Common electronic problems include bad connections to the motor that advances the ribbon (cold solder joints, cracks in traces on flex cable to carriage), bad motor driver chip, or bad motor.
Mechanical problems include stripped or broken gears, misalignment preventing advance mechanism from engaging, and defective ribbon cartridge.
(From: Roger D. Waddell (rwaddell@peachnet.campus.mci.net).)
This problem is usually caused by a broken 'E' clip on the bottom of the print hammer solenoid. The clip holds on a lever that works in conjunction with the ribbon/correction feed solenoid near the right front of the print carrier.
When the clip breaks, the lever falls out of position and never trips the lever that assists in feeding the ribbon.
I have seen this problem many times!!
"My Imagewriter II, after many years of faithful service (~8), is starting to squeal. It squeals when the carriage moves. It still prints perfectly fine, but....a new noise can only mean trouble. Does anyone have any experience with this problem and his solution? I imagine it would take only a drop or two of lubricant. But where?"
(From: Chris Jardine (cjardine@wctc.net).)
I would suggest that you might have a problem with the ribbon mask. A few years ago I was the service manager at an Apple dealership. I can't tell you how many ribbon masks I replaced for many different problems, including wierd noises. It could also be a problem with the carriage drive motor. I can't remember which side of the printer it is on, but, it is below the gear/pulley that drives the toothed belt. You might try some very fine (maybe silicone) oil there and you might want to clean and then re-oil the carriage guide bar (the shiny round bar) and the bushings on the carriage that ride on the bar. The only other possibility would be a problem in the gears below the ribbon that are responsible for driving the ribbon.
Try powering on while holding escape, this will put you into service mode. Press the up arrow to start the engine test, if this works you may have a problem with the xerox controller board.
Try disconnecting all the n/w cables and reseating the cables on the system board. Remove this by the two thumbscrews at the back and slide out as far as you can then pull the cable off.
I have a Compaq Pagemarq 15/20 service manual that I am selling, but I am in the UK, where are you?
"I just received the above printer in a non-working condition. It exhibits the following symptoms:When power is applied, the head appears to try and move, but will not unless you manually get it started. Then it goes to its home position. You then hear three beeps, and nothing else can be done to elicit any response from the printer. The power LED comes on, but the paper-out will not, regardless if there is paper installed or not. The paper detect switch is working properly (checked with ohmmeter by inserting/removing paper while across switch). Also, I hooked up a resistor and +5 V to the paper-out LED, and it lit up ok. I have also mapped out the stepper motor leads, and resistance checks show that it appears to be ok.
MY question is if perhaps I lost one of the outputs for one of the stepper phases. The controller seems to be one large power-ic from what I've traced out."
Could be. Do you have a scope? You could check the phases.
"I know if you keep voltage across one phase, you can lock a stepper. If you lose power to one phase, will the other phases keep it going provided you manually start it like I'm doing?"
Also check for bad connections to the stepper from the logic board - I have seen these on printers.
It doesn't explain your other problems, however. Once initialized, even though the print head doesn't move properly, I would expect the printer to work in other respects.
(From: Joe Wagg (jwagg@fs.cei.net).)
The 3 beeps tell you there's a carriage error, probably from an incorrect number of steps needed to reach the home position. Since you've already checked the motor, the next step is to check the motor drivers. Using a meter with a diode check function, put the red lead on ground and the black lead on each phase coming from the board (disconnect the motor first). The readings should be within 20 percent of each other, not open or shorted. Also make sure the motor, pulleys, and carriage are all relatively clean and move freely. The other symptoms are caused by the carriage error, which halts the cpu to prevent damage. Clear up the carriage error and the other problems should go away. You should also make sure that all socketed chips are properly seated and don't have dirty contacts.
"I have an Epson LQ-570 series dot-matrix printer that has developed an intermittent paper feed problem over the past year or so. It uses a push tractor for sprocket-feed paper, and paper tends to bunch up under the platen. There doesn't seem to be an obvious way to remove the platen to see what the paper's catching on, indeed the FAQ on Epson's website says it can't be removed, and to bring it in to the dealer for repair."
(From: Asimov (Asimov@juxta.mn.pubnix.net).)
Remove everything that is normally accessible. Then flip the printer on its back and play a vigorous drum roll all over it. This should dislodge a huge amount of "holes". Didn't you always wonder where those perforations went? Well, some of them make it into clogging up under the platten.
Flip the printer on its side and with a thin brush dust the remaining grime away. If the jam didn't clear up you might try manually inserting a stiffer paper (postcard, greeting card, etc) a few times before dismantling the platen assembly any further.
"Got a problem with a real nice 24 pin dot matrix printer I bought used. Was working fine for awhile then all of a sudden it will be printing fine an the printhead intermittently will jump to the center of the carriage and start printing from there. Also, when you turn it on, many times the printhead jams over to the right side of the carriage and the gears grind and you have to cycle it on and off to get it to start up right. Then you now almost for sure it will have problems printing. Help, any ideas? Do I just change a control chip? How do you scope out something like that? Can I get a manual somewhere? I want to keep the printer."
Also check for bad connections. If the printhead motor is a servo (DC instead of stepper), you have an intermittent feedback problem, again could be bad connections or bad parts.
(From: Ralph Wade Phillips (ralphp@gcstation.net).)
First off, have you changed the RIBBON? Second, clean the print head carriage rails. They need a VERY LIGHT coat of VERY LIGHT oil, then wiped clean.
Usually, when I see this, either the printer is just plain wore out, or the ribbon is snagging. Since the ProPrinter family drive the ribbon off of the carriage drive, if it ever snags, you'll get these symptoms.
"I have a NEC printer that has an intermittent CE (ribbon cartridge empty) problem, only the cartridge is new and good. Anyone knows what senses this condition and what part could be affecting this? NEC wants $20.00 just to talk to me. Thanks for any help."
(From: Paul Weber (webpa@aol.com).)
Look at the old ribbon. Does it have a short piece of transparent tape at the end of the ribbon? If so, the printer probably has an optical end-of-ribbon sensor; a LED/phototransistor pair that looks through the ribbon. Does it have a short patch of aluminum foil tape (probably on the back side of the ribbon) ? If so, there is probably a pair of contact fingers that rub the back of the ribbon as it feeds. Look for bent contacts or debris in the ribbon holder mechanism.
Look at the ribbon holder mechanism in the printer. Is there switch or contact pair that could sense the motion of the ribbon cartridge's feed reel? If so, check for free movement and cleanliness. Does the ribbon holder move with the printhead on this machine? If so, check that the ribbon cable connecting the carriage with the remainder isn't damaged and is connected properly at both ends.
"I am having a problem with a OKI Microline 391 Elite. I opened it up and cleaned out the dust and paper from inside. On putting it back together and powering up, The SEL light, the COURIER font light, LW and 10 cp light are all flashing and the stepper motor for the platen is jigging back and fore about once every 3 secs."
(From: Glenn Allen (pclogic@xtra.co.nz).)
These printers generally need just a clean out and put back together.
I would try to reseat the main logic board first, also try cleaning the edge connectors. There is a plastic joining bracket between the print head cable and the main logic board.
If you are getting bad carriage movement then check that the carriage can move freely back and forth, also check the black teethed guide lying on the bottom for clogged teeth. The print head ribbon can be removed for better testing. if the carriage doesn't move freely then you may need to adjust it's position by loosening the two screws on either side of the print head carriage and then adjusting back and forth until good movement is achieved.
"This printer has a problem I am lost with. When I power it up and attempt to have it perform the self-test printout (FF on power up), the print head moves back and forth, the paper feeds, but the pins don't actually fire. However, if I connect the printer to a computer, the printing is just fine."
You are complaining? :-) Usually, it is the other way around!
(From: Ralph Wade Phillips (ralphp@gcstation.net).)
Eh? On the SD-15, the FF SelfTest is for checking HEAD MOVEMENT only. It sounds like it passes just fine!
Try holding down LINEFEED button instead. :-)
Hewlett Packard has on-line information and documentation at:
The PaintJet printers are 180 DPI and the DeskJet printers are 300 DPI. The resolution of the PaintJet is about that of a poor 24 pin printer. The PaintJet and ThinkJet printers are also PCL, so you can use a HP laser printer driver set to 150 DPI.
There seem to be currently four levels of HP ink-jet printers:
(From: Paul Grohe (grohe@galaxy.nsc.com).)
I've dealt with a few of these buggers before! ;^)
Is yours a DeskJet, DeskJet Plus, or any of the DeskJet 500 or 600 series?
If not, then ...well....then I may as well tell you this anyways because you will probably run into these some day....(some of the below can apply to other ink-jet printers).
Try holding down 'FF' during power-up, you may get a different test page. One of the pages should have a jet-test pattern (A slanted diagonal line separated by 11 vertical marker lines and little jet ID numbers).
The first page of the standard self test results in that pattern.
I first tried the cartridge that looks exactly the same as the one that came with the printer (though the part number is different). Then, I tried another somewhat larger one that apparently has identical connections.
The different part numbers are the 'standard capacity' and the 'high capacity' cartridges. They're interchangeable.
I assume you have cleaned the contacts (with a Q-tip, on both cartridge and socket). Use a magnifying glass and check *each* of the gold 'bump' contacts. Repeated cartridge swapping, or improper insertion, can cause a crack to form around the base of the 'bump' and the pad (or the pad and the trace). The 'bumps' can also be 'flattened' by cartridges that were forced in at too much of an angle. There should also be some 'give' or 'sponginess' to the contact area to assure even contact with the cartridge.
Check for broken/bad traces in the flex-cable that goes from the driver board to the cartridge. Ohm out the cable between the supply commons and the individual driver lines (at the PCB) with the cartridge in place. I think the jet resistance was about 50 ohms (It's been a while). There were four separate jet sections (commons). All four commons were tied to the +20V supply through four separate (12 ohm?) series current limiting resistors. The driver outputs seemed to be grounded emitter, open collector (w/clamp diode?). The jets themselves are driven individually and are not multiplexed.
To test, I printed an all-black page (with an empty, but installed cartridge) and watched for activity on each of the lines at the PCB end. Good pulses are 'bi-levelish'. Normally negative going 20V, with pulses down around 15 V, and going all the way near ground for that particular jet. The commons 'bounce' because of the shared series current limiting resistor, causing the numerous smaller pulses around 15 V (caused by the firing of other jets sharing that common). A bad connection will show up as a weak or distorted pulse. An open or broken line will show up as 0 V. I theorize that a bad driver would show just the smaller 'line bounce' 15 V pulses and a shorted driver would show 'GND' (and also would blow out that jet!).
The current involved to drive the 'jets' is a pulse of short duration and pretty high current. Any poor connections will cause excessive I/R drop and the jet may not fire hard enough. A sign of this is drops (dribbles) of ink that form on the head during printing.
While you are in there, check and clean the rectangular rubber seat that the cartridge rests on in the 'parked' position. Dry ink can cake up on it, causing a faulty seal and resulting in dried-up cartridges ($$$!). The rubber seat pulls off and is easily cleaned with a wet paper towel (wear gloves, or you will suffer the dreaded 'black finger syndrome'). Also clean the 'nose wiper' that sticks up about a centimeter to the left of the cartridge seat. This always cakes up and can cause printing problems.
To manually prime an uncooperative cartridge, you do not have to suck on the business end. You can gently blow into the top vent (located on the top of the cartridge, inside the green arrow) to prime it. But be careful!; If the jets are severely plugged, ink may blow out the check-valve on the bottom (under the plastic 'flap' with the 'maze-like' area). Very messy! Have a towel ready!
The old DeskJets were (and still are) notorious for paper feed problems as they age. This is caused by the three big paper pick-up rollers drying out and becoming hard and smooth. Roughen them up with some rough sandpaper. The HP FTP site has a article about this in the DeskJet DOC directory. A free kit is available from HP (to qualifying S/N#'s) that 'dresses' the rollers (basically forces the rollers to turn and sandpapers them).
OH! Biggie! Another big 'failure mode' of the early printers is that the paper sensor lever will jump out of position and jam if the printer has suffered some rough handling (especially if it was turned upside-down or on it's side). The paper sensor lever (pivot) is located on top above the middle roller. The other end breaks the beam of a photosensor. The 'interrupter' end will move over just enough to wedge itself above the photosensor. This is cured by simply raising the lid and wiggling it until it drops back into position (I have 'fixed' many an alleged 'broken' printer this way). The 'interrupter' end seems to have been made larger on the later printers to prevent this.
From time-to-time, the cartridge's nose should be wiped clean with a soft, moderately damp cloth (~ every 100 pages). Keep the 'business' end pointed down when handling/cleaning the cartridge (Yes, this means hold it above you and clean it from the bottom!). This keeps the galleys and jets primed.
I concur. If just *one* jet is not firing, then it is on the driver/flex- cable/connector/cartridge side. All the nozzle decoding is done on the driver board, so the 20 pin interconnect cable is okay. The DC (well..really 20VAC) power connector does take some abuse in normal service, this could have aggravated the cold joint.
Don't forget to check the buttons for water damage/contamination.
Do you know what the difference is between the DeskJet and PaintJet cartridges? There is at least one contact that is open on a DeskJet cartridge and wired to something on a PaintJet cartridge.
I also have a color PaintJet 300 with a possible "dead" driver line, but I focused my attention to the ailing DJ500, so I did not have a chance to "buzz-out" the PaintJet cartridge. From looking at it, it looks like the PaintJets are multiplexed in some way (there are more jets/contacts than wires in the flex-cable). I never got around to fixing/looking into it (it's still sitting there).
BTW 1; The DeskJet, DeskJet Plus and DeskJet 500 (non 'C' models) are basically the same (except for some internal fonts). The DeskJets speak PCL, so if a driver for a DeskJet is not available, you can use a basic HP LaserJet driver (but the margins may be cut off, as the DeskJets print area is not as big).
These things are so damn simple that not much can happen to them. I have yet to run across one with a severe electrical problem. They are always minor mechanical failures (or missing power bricks...$35 from HP).
All the DeskJet/DeskWriter printers, up to and including the 6X0 series, use the same B&W cartridge as the original DeskJet. Those cartridges will still be available for some time. Your printers life is not over any time soon!
The DeskJets are good, sturdy and reliable printers (as long as they are well maintained) You did clean the rubber cartridge seat and flap. Right?.
BTW 2: For maximum cartridge life, make liberal use of the "draft" setting for "not-so-important" printouts (or, er, um, drafts!). It also prints faster because it "swipes" once per line instead of twice.
BTW 3: Use the cheap 'Shark' brand inkjet paper for best results. Pretty near laser quality! Regular copy paper tends to bleed, but is fine for general use.
Can you tell I have a 'few' of these printers around???? ;^)
At random times, the print will fade out and require priming by mouth to restore operation. This can be anywhere from a few lines to a few pages. Until it quits there is no evidence of a problem. Blowing into the vent hole will restore operation. This happens with more than one cartridge. It appears as though the ink is just not refilling after being vaporized.
Is the cartridge full? As you get down to the last 20% or so of the cartridges capacity, it tends to start doing this. I guess there is not enough pressure "from above" to force the ink down. If you can start seeing through the cartridge, you are probably near this point.
In troubleshooting the printer, you tend to "burn up" cartridges a *lot* faster than in normal use.
This can be a symptom of the print head not seating firmly when in the "parked" position. Use a dental mirror and make sure the seat presses firmly against the head. One cause of this can be turning off the printer before it has a chance to run through all of it's "housekeeping" cycles at power-up, reset (re-boot), or after printing. During certain parts of the cycle, the head is moved slightly, or the cover is moved. Turning off the printer too soon may leave the head exposed. Always let it finish, then turn it off (warn others about this).
If you haven't already, just pull the thing apart and give it a good overhaul (get your favorite pair of Torx bits ready!). Clean all the rubber tires, seals and "nose wipers". Wipe off the slider bar to remove any old lubrication. If there was a serious ink leak and the printer was involved in some "circus acrobatics", some of the ink can get on the slider bar and contaminate the factory lubrication, causing it to become "pasty". I wipe the slider bar clean with a cloth then apply a *light* coating of a light, teflon-type machine oil with a cloth (I use "Tri-Flow", a spray-on type usually found in bike shops).
BTW 4: In the winter months, with it's low humidity, the rollers will shrink even more, causing even more paper feed problems. This is also compounded by the fact that the paper sometimes develops a static charge and tends to "stick" together. Sometimes it pulls two or three sheets in at once, or the paper sticks firmly together in the tray and the weak, dry rollers cannot pull the paper in. Just remove the stack of paper and "fan" it out to loosen it (especially if it has been sitting there unused for a couple of weeks).
These printers are, like some other things we won't mention, 'Use `em or loose `em'! They work best with frequent use. They do not like sitting around for months unused. Three months seems to be the limit before a 'good' printer will start to dry up from no use.
How is pulse width determined in these things?
I never really investigated the timing of the pulses. I'm not sure how they vary the pulse width. I looked at the pulses when it was doing the first page of the self test, which is mostly text, and all the pulses seemed to be the same width.
Happy printing!
The ThinkJet is VERY simple. The ThinkJet printers (and clones) do not employ any type of printhead covers or 'priming stations', so the cartridges are prone to drying out if not used for a while. A quick 'priming' is usually required, even after only a week or two of non-use.
The cartridges also tend to leak if placed in odd positions or subjected to rapid temperature changes. Make sure the cartridge has not drooled on itself and caused ink to cake down on the contacts in the holder. Clean the gold contacts *gently* with a cotton swab moistened with rubbing alcohol.
BTW: Like motor oil, fresh ink is great for cleaning up old, dried-up ink.
The ink is contained in a rubber bladder inside the plastic shell. There is a hole in the 'butt-end' of the cartridge. *Gently* stick a bent paper clip in and push on the bladder to prime it. A drop of ink should form on the printhead. Use a piece of tissue to wipe the drop off and re-install the cartridge.
Note that there are two types of HP ThinkJet printheads. One is the older, original type meant for printing on special 'ThinkJet' paper, and the newer 'Plain Paper' ones meant for, well, plain paper! ('PLAIN' will be printed on the side of the cartridge).
The older cartridges printing will appear very light if printed on plain paper. Make sure you have the 'Plain' type. Note that even with a 'plain' paper cartridge, the printing is lighter than a Laserjet or DeskJet, especially in draft or single pass modes. Don't expect razor sharp printouts. This was the first Inkjet printer!
As for the missing jets, eyeball the cartridge contacts and see if they appear straight and aligned correctly. The contact area could have slipped and may be out of alignment (although rare).
The flex cable/connector assembly is held in place with a pair of plastic bars. The "bars" have two pins that snap into the 'carriage' (they also provide alignment).
If the contacts appear to be out of alignment, carefully pull out the plastic bars to release the contact pad, realign the holes and press them back into position. Make sure the rubber 'bumps' behind the contacts are clean and undamaged.
(This makes more sense when you actually see it :^))
Be careful! Nothing needs to be forced.
"I have an HP ThinkJet 2225C printer. I just replaced the print cartridge. It still doesn't print dark enough, and even after I primed the cartridge a few times, it still also misses a dot at the top and the second one from the bottom.I'm wondering, could the voltage to the cartridge be too low?"
(From: Kevin).
I have seen on rare occaisions the cartridge bad out of the box! Try wiping down the cartridge head & contact points on the printer with a Q-tip & alcohol. Sometimes blowing in the vent holes will force ink out the head, wipe off excess and try it. You may have to repeat the procedure a few times. If this doesn't work get another cartridge. You may want to try swopping the bad cartridge into a working unit or taking a working cartridge and putting it in the suspect printer.
(From: Frank Reid (reid@indiana.edu).)
I agree with all Kevin said. I use blue window-cleaner (e.g. Windex) instead of alcohol; the ink is very soluble in that stuff, and it penetrates the tiny holes in the printhead. After cleaning, hold a rag over the printhead and sling it downward a few times (as if throwing, but don't let go), such that centrifugal force pushes some ink out. If that doesn't work, try blowing on the upper vent.
On a few rare occasions I've encountered bad connections at the fixed end of the printhead cable, fixed by reseating the connectors. Also, if the cartridge has leaked, there may be ink on the gold pads in the moving end of the printhead connector, causing bad contact. Clean as above.
Some of the later models, including the type which takes two cartridges (3-color and black), have screws at the end of the carriage rod which allow adjusting the clearance between printhead and paper. Those may need adjusting if the ink is smearing. If too light, it's probably a printhead problem.
(From: Richard M. (Digitech@bogus.net).)
It is a water based ink. There is no need for any solvent other than water. Warm water works well. Use it all the time on my 1200C and DJ750C... BTW, I never have to touch my Epson. Use lint free cloths to tamp dry. NEVER wipe.
(From: R. Wagner (rwagner@ncn.net).)
I found the cable from the computer to the print head had some open places close to the head. The want 35 dollars for a new one. I went to the auto parts store and got some a rear window defroster repare kit. I got it working but for how long I dont know.
The paper feed problem afflicts the HP DeskJet 550C and 560C, DeskJet 520 and DeskWriter 520 printers produced between June 1993 and March 1994. The affected units have serial numbers beginning with 'US3' through 'US43.'
The problem seems to be that the rubber rollers become slick over time and then the paper doesn't always feed properly. Last year HP offered a free paper-feed cleaning kit to fix the problem. Try contacting HP at 800/656-2324 or 510/657-1473 (FAX) to find out if the free kits are still available.
(From: Allen E. Amey (a_amey@ix.netcom.com).)
Try contacting the manufacturer. I have heard that HP has a free kit for the 500 series printers. The kit dresses the rollers and is supposed to be a fix for the type of problem that you are experiencing. BTW, using alcohol can actually compound the problem by prematurely drying out the rollers.
(From: FaxRepair (faxrepair@aol.com).)
I believe the only replacement part would be the entire paper pickup assembly which may need to be replaced because the gear train is damaged from ink having dripped onto it. Once the gear train is out of timing there is no known cure. Clean the rollers with rubbing alcohol and a soft cloth. If it doesn't pick up the paper after cleaning the rollers, then remove the entire print assembly and look for signs of ink on the gears at a location directly below the ink cartridge's home position. On a few occasions I have had success by flushing the gear mechanism with warm water to wash away dried ink.
(From: James E. Burke, Jr. (jeburke@ibm.net).)
I fixed one for a friend a couple of months ago. Parts are not available (well, you can get them, but they're too expensive).
In the one I fixed, it was a broken plastic part that caused the misfeeds. To get to the part, I had to disassemble the whole printer.
If you decide to to this, check the two 'fingers' that are behind the print head when it's in the parked position. The hook on the tip of one of them was broken off. I found the broken part inside the printer and glued it back on with JB Weld (twice--first time backwards). The pair of 'fingers' are identical so you could probably swap parts from one of the other machines instead of attempting the repair of the "fingers".
(From: Paul Grohe (grohe@galaxy.nsc.com).)
I have the same problem.
The rollers dry up and become glazed-over and smooth. You need to 'rough' them up.
Try sandpapering the wheels with coarse sandpaper (100 to 200 grit).
You'll need to trick the paper sensor. Take the cover off and lift-up on the black paper sensor lever. Then hold the piece of sandpaper firmly against the wheel and hit 'FF'. You'll need to do this repeatedly, as the wheels will only spin a sheets' worth each time.
Do this until the wheels feel 'sticky' again.
It also helps to keep the paper tray full at all times (but not overloaded).
Unfortunately, they'll never be like new.
(From: Frank Reid (reid@indiana.edu).)
I've had very good results cleaning the rollers with naphtha or mineral spirits, no sanding. It removes the glaze from the clay content of the paper, and makes the rollers softer.
(From: (Egiglious Giggles" (chsoccer@prodigy.net).)
The thing I have come across, is the spring which is directly under the roller itself. The purpose is to allow tension on the roller for pulling the paper in one sheet at a time. If you look directly in the middle under the roller from the front there is a guide that is spring tensioned. You have to take the roller assembly apart to get to it. But, if cleaning the rollers doesn't do the job, this is probably the culprit.
(From: Tony Dunlap (tdunlap@odot.dot.ohio.gov).)
The "Glaze" that gets on the rollers is often due to the rag content of many cheaper papers (especially "Recycled"). To clean the rollers:
(From: Paul Weber (webpa@aol.com).)
HP had a free upgrade kit for the 560 to solve this, maybe for the 500 as well. It was a replacement for the silicone rubber park-position nozzle seal. Also remember that the 500 came with a cartridge storage box with an elaborate rubber seal in the bottom; they encouraged you to remove the cartridge from the printer and put in the box whenever it wasn't in active use to prevent dry-outs. Finally, HP cartridges have expiration dates - and they mean what they say: If they're out dated, they work poorly or not at all.
"Whenever I send a heavily formatted print job to a DJ340 printer, it prints 1/3 to 1/2 a page and then power shuts off! This so far has happened in TTAX97 and Netscape 4.03. OS is Win95 and I'm using the latest driver for this printer. The printer otherwise prints test pages and simple jobs OK."
(From: Paul Grohe (grohe@galaxy.nsc.com).)
I know this sounds silly, but how old are the batteries?
My guess is that the battery is probably getting weak. Heavy graphic content and "fancy" fonts users (of which TTax and Netscape qualify) will "swipe" the head more per line than the "text and lines" of the test pages. Moving that print head uses a lot of power!
Does the unit work on the adapter - without the battery? If not, then it relies mainly on the battery for power, and the adapter just charges the battery in between jobs. A weak battery could be drained after a short time.
If it works without the battery, then the battery could be going bad, causing the charger to dump too much current into the battery and "rob" some of the power from the printer.
There is a "Troubleshooting" note in the printers "FAQ" on HP's site.
It basically says to check the batteries and make sure you are using the correct power supply.
Try replacing the battery. If you bought it at a local store, take it back and see if they have another battery to check it with.
"I just picked up an HP DeskJet 520 printer that doesn't work. On startup, the print head moves right an inch, then all the way left, where it slams into the left side of the carriage and grinds away for about a tenth of a second before stopping."
(From: Tech Guy (patrickmcardle@sprintmail.com).)
You may wish to check the undercarriage (no pun intended).
The printhead location sensor microswitch may be on the fritz The printer uses this switch to determine the starting point of the printhead after which it uses assumed location by how far the data has sent the head every time the unit gets a reset code, it checks this switch and if the signal is not detected, it may slam the head to either rail end or not move at all. If this is the case you can make sure that the platen is not clogged with label or paper debris. Gently move the head by hand to the right. If you shine a bright light into the area where the printhead usually calls "home" you may be able to see this switch (it may however be located under a cover triggered by the belt) if the switch is defective, replace it. If in fact it is jammed by debris, simply clear it and you may have solved the problem. Beyond this, you may have a logic problem (bad chip or other component) I make a good practice of doing a thorough cleaning of all machines that have left my shop to reduce the possibility of other problems during my warranty period. (it also makes the customer think that they have gotten something for their money)
I have replace a switch or a fuse on many machines, charged my base fee and heard the response upon their pick-up by customers that, "I can tell right away that you have found and fixed the problem" without even so much as a demo.
(From: michae98@ix.netcom.com).
There is a clear plastic strip strung between the both ends of the printhead pathway. This strip of plastic has microscopic vertical bars which the printhead can read and sense what position its in the pathway. The strip may be contaminated with excess ink which may confused the printhead. Take a soft cloth or Q-tip dampened with water and wipe of the strip (the ink is water soluble) and the printer should work.
(From: Raymond Carlsen (rrcc@u.washington.edu).)
Closely examine the toothed belt that drives the printhead. Look for a few missing teeth at one end. I managed to make one work again by shifting the belt over a bit (past the bad teeth). If that's it, the belt should of course be replaced.
"I have a HP DeskJet 560C, Model C2168A that is behaving badly. When I power it on initially, it appears to run through a diagnostic self-test (as evidenced by the sequence of LEDs on the control panel). It gets to the point where it moves the print head and that is where things go bad. I think it is attempting to report some sort of error code because it then flashes some of the LEDs in a repeating pattern (more on that later).First let me describe mechanically what it is doing. When it gets to the point in the power-up routine where it moves the print head, it should do the following:
- Move print head to the extreme right.
- Prime the print head (???), a stepper motor on the right raises a mechanism to contact the print head.
- Position the print head in a ready position.
OK, here is what it is doing (please forgive my feeble attempts to describe in words what is happening):
- I hear three distinct sounds (whirring of various stepper motors I think) before the print head moves.
- The first two sounds seem normal from what I can remember when the printer used to work.
- The third sound is the loudest and doesn't sound at all normal. It sounds as if the stepper motor that does the priming is oscillating back and forth between two "steps" (the sound is like a stripping gear).
- The print head moves approx. 1" to the right.
- The print head immediately moves approx. 1.5" to the left (note, this sequence of print head movements happens bang-bang (no delays between movements).
The end result is that the print head winds up about 0.5" to left of the position it was in when the unit was powered on. If I continue the power on sequences enough times it will end up at the extreme left and will be accompanied by a much uglier, more sinister sound of the print head slapping against the leftmost guard (as if the printer is attempting to throw the print head through the case).
Now let me describe the sequence that happens with the LEDs. The control panel has 9 LEDs arranged in three columns of three LEDs each. The leftmost column of LEDs lies between the "CLEAN" button at the top and the "Font" button at the bottom. The middle column of LEDs lies between the "Alignment Test" button and the "Status" button. Finally, the rightmost column of LEDs lies between the "Install Print Cartridge" button and the "Quality" button. Here is some ASCII art:
CONTROL PANEL =========================================================================== || || || Alignment Install Print || || RESET CLEAN Test Cartridge || || || || ,--, ,--, ,--, || || ( #1 ) ( #4 ) ( #7 ) o o o || || '--' '--' '--' || || || || ,--, ,--, ,--, || || ( #2 ) ( #5 )Busy ( #8 ) o || || '--' '--' '--' || || || || ,--, ,--, ,--, || || ( #3 )Condensed ( #6 )Ready ( #9 )Econo Mode || || '--' '--' '--' || || || || Load/Eject Font Status Quality || || Paper || || || ===========================================================================I have numbered the LEDs (using my own numbering scheme) so that I can reference them below.Here is the sequence that the LEDs progress through each time the unit>is powered on. The sequence is always the same.
LEDs On Duration Description ----------- ---------- --------------------------------------- 1. 123456789 2.5 secs Happens immediately when I switch the power on. Then LEDs 234789 turn off. 2. 1 56 0.5 secs This is a flash (longer than a blink). Then LED 5 turns off. 3. 1 6 2 secs Then LED 7 flashes on. 4. 1 67 0.5 secs This is a flash. Then LED 7 turns off, LED 5 blinks on. **5. 1 56 ---- Here LED 5 just blinks on then off. 6. 234 789 This starts the alternating sequence where I believe the printer is trying to report an error code. 7. 1 6 This is the rest of the alternating sequence. The printer then repeats these two patterns forever (LEDs 234789, followed by 16).** Step 5 is the point where the printer starts moving the print head."
(From: Jason D. Pero (JDP6640@ritvax.isc.rit.edu).)
The grinding sound from priming area is the jammed lever black stick that is pushed towards a bit towards right. If it good, it should be in upright position. If stuck too very right, unstick it by pushing it back to upright position towards left. This stick can be seen between the carriage rod and the printhead's purging rubber nipples and wipers. Also clean (gently!) the clear plastic strip with that fine black lines on it. First the clear strip must be removed first before doing this operation: The sensor is behind the printhead riding the clear strip, remove it by unengaging two triangular fingers inwards from outside and pull the sensor unit outwards towards back. Dust off inside that sensor gap and snap it back in.
Finally clean and oil both carriage rod and the angled underside area where the bearing block contacts upward onto it. Oil that carriage motor carefully and all stepper motors.
That should solve everything. This have happened to my 520, and my friends' 540 and 560C. Pretty common problem! Usual action when misbehaving is slamming either stops or do a "rushed start/stop" and some odd scary noises. All complains with pretty, interesting alterating flashes from the LED's on the control panel.
Pure or almost pure alcohol stuff is best as it does not melt anything or rub marks off and some 2 in 1 heavy duty oil "blue band" can. Top and bottom white shells comes apart easily after unengaging four snaps, doing one at a time and pulling gently and with a small flat screwdriver. Top off, the engine is free. disconnect with care to both ribbon cables one for carriage motor, and the flat white ribbon, or in some models that uses dual printheads, unplug another stepper motor. All connections you need to worry about is only from the mainboard side. Then the print engine lifts out without any fastening hardware.
WELL DESIGNED 5xx series compared to many printers past and now! I have a 520 chugging away after this fix and real cheap for that printer from a owner who does not want it.
Only problem is cost of cartridges. :( $50 of two versus $13 can of toner powder for an Okidata 400 that will last thousands of papers. Only problem is Oki. 400 LED laser thinks (processing graphics) very slowly. Is there a hack to swap the proper circuit boards from other similar Oki 400/800 series to make it work faster and more useful than a pokey 186 cpu equipped Oki 400???
Your comments and suggestions on which brand of refill inks that is perfect for those cartridges. I know how to refill it right after experimenting on a bad cartridge and successfully refilling one good cartridge from a bad cartridge (dead jet out of 48 jets I think).
(From: Glenn Allen (glenn@manawatu.gen.nz).)
It is not a stripped gear is it?
The old DJ500 used to have 2 levers on the right hand side at the back that went up and down. Sometimes these got stuck and noises could be heard. Normal paper feed problems here.
A problem with a DJ850 was that paper got stuck and to get it out I had to remove the paper feed motor on the drive shaft, when put back it would bang the left hand side of the case. Needles to say it needed the cog setup back to right place it expects when powered on.
Those printers have an index strip that the printhead follows doesn't it? Is this clean, i.e. Not ink all over the place.?
Lastly if you are repairing and turning your printer up and down, check you do not lose the rubber cap where the printhead sits, and clears the guns, If you do your cartridges will become clogged in no time.
Also clean the print head shaft, any gunk on it will cause the printhead head to stick thus giving error light or worst powers down the printer.
The HP printers test for the presence of a cartridge by checking the electrical voltages on the contacts between the cartridge and the cable. The slightest amount of dirt on the contacts can give a false reading making the printer think that no cartridge is present. If cleaning the contacts does not work you will have to buy a new cartridge.
"My HP Deskwriter is just over the warranty of one year and when I print text instead of white lines through the type which would indicate to clean cartridges or replace them, I get black thin lines almost smearing slightly the text."
(From: Dennis Bathory-Kitsz (bathory@maltedmedia.com).)
For this last, there may be some diagrams accessible via the HP Support Page.
The bad news is that the plastic these parts are made of seem to be a Teflon hybrid and even the best epoxy doesn't last real well.
The even worse news is that DeskJets are disposable, just like Bic lighters.
HP will NOT sell you any internal parts.
They will not sell them to your dealer.
They will not even sell then to a so called HP service center.
All DeskJet service takes place in Corvallis, Oregon. A second possible location is Mississauga, Ontario but I think they just forward printers to Corvallis.
Here's the deal as I've been told; you pack up your printer and courier it to Mississauga, ($40 Cdn.), pay $175 Cdn. for a refurbished version of your Deskjet, and then pay another $40 Cdn. to ship the refurb back to you. That's $255 Cdn for a used printer when there are any number of new printers that can be had for a comparable price (and would also have a warranty).
That, to me, means DeskJets must be disposable because nobody in their right mind would pay that much for a three or four year old printer. It's bad enough when you consider 540's, which back then had a 3 year warranty, think about all the poor suckers buying newer HP's with only a 1 year warranty...
That's got to be enough harping on my part, the short of it would be that if you've got it working and your cartridge parks okay, it might be best to leave it alone. You won't get any worthwhile out-of-warranty help from HP. Check on parts availability on any future new printers you might ever buy. You can't assume that they won't forget you the day your warranty expires.
"Does anyone know where the problem might lie with my HP printer? The problem is that when it is turned on, it goes through the reset sequence until it reaches the park zone, then it seems to miss a gear or something by the sound of stripping gears, then the lights flash alternately. My workaround to this is to turn it on, let it start across on it's reset sequence, turn it off, then right back on, and it will initiate just fine. Another anomoly is that when printing large color graphic files, occasionally, it will make it part way through the page and just stop with the same flashing error. After resetting it, it of course will print garbage unless I resend the data to the printer all over again. Any ideas? I've left a message on the HP site, but there has been no response."
Call HP - After much hassle they finally admitted it was a defect and replaced it with a new 600 series. I had the same problem - but had to call Idaho to get results.
(From: Ralph Wade Phillips (ralphp@techie.com).)
Did you also clean the cartridge HOLDER? See HP's web page for more details, but I've seen SEVERAL of the 600 family that have "dust" collected under the cartridge holder. Since the black hits at a different angle than the tricolor cartridge, it is more prone to hitting the dust buildup, causing excessive smearing.
BTW, beware of flipping the entire printer over to unlatch the top - you may get a shower of the last n years excess ink from the holding tank!
(From: Paul Grohe (grohe@galaxy.nsc.com).)
Go to this page below, scroll down to the "power module options" section, and pick the correct adapter part number for the UK.
Then do a net search for that part number, or, contact HP directly. Last time we ordered some, they were about $35US from HP.
I had a similar problem with a HP 693C. The problem was the spacing between the paper and the carriage. A suggestion: if you're not mechanically adept, don't tackle this, get someone who works on printers to lend a hand.
I have not taken my 600C apart, and will not do so unless it fails, so the following information is based on the 693C, a similar printer.
The top cover is held in place by some latches, and a couple of screws under the paper tray. Be careful while tipping the printer, there is a catch-basin for the ink, and if this spills you will have ink dripping inside the printer. Remove the upper cover. Be careful with the thin cable to the electronics board. At this point you should be able to check for any gobs of ink that have turned to paste. Clean the dried ink off of everything, especially the bottom of the carriage, and print a test page. If it still smears, it's time to try adjusting the carriage height.
On the 693C the carriage slides on a rod that runs the width of the printer. The anchors consist of a screw through a slotted hole. On the one I fixed, the screws had obviously been loosened (they're torx screws, and it was obvious that something such as a jeweler's screwdriver had been used on them). Anyway, loosen the screw at one end, lift the rod slightly, and retighten. Print a test page, and repeat if it still smears. Of course, if it now smears only at the other end, it's time to switch ends.
I'm sure at the factory they use a gauge to adjust this to within a micron but the empirical approach worked for me.
I did a search when BOTH of my HP692C DeskJet printers started getting flaky. I didn't find much except for a post mentioning that cleaning the small plastic 'barcode' may solve most problems. While this is exactly what HP customer service suggested as well, it didn't solve my problems.
What the printers were doing, were randomly locking up. They also started making a 'knock' sound while they were printing. But, the 'knock' sound was more prevalent than the actual 'locking up' problems. But they would still lock up more than twice a day.
What I found was happening was that the stepper motor belt was skipping a tooth when the print head was changing directions. There is a black plastic tensioner arm on the left side of the printer that holds the belt tight and this was getting yanked in enough to let the stepper belt have some slack.
What I did to fix this was to take the spring out from behind the black tensioner arm and stretch it out to put more tension onto the stepper motor belt.
Both of these printers have had heavy use, they both are just over 1 year old right now too. I only moderately stretched the first spring and it still made the 'clicking' noise every so often. On the second one, I probably stretched it about 1/2" to 3/4" in it's fully relaxed position, but I think when putting it back into place it probably bent back a small amount. This worked well, the belt did not feel overly tight and I have not had ANY problems whatsoever. :-)
I've been having a problem with the black cartridge in my HP 820Cxi printer getting all gummed up with ink on the bottom, making lousy print. Clean it off, and it comes right back. It also was missing a horizontal line or two - thin but noticeable. The "clean" instructions with HP troubleshooting didn't help at all. Interesting that they say there is another thing you can try, but don't do it except with NEW ink cartridges! At $30 or so each, I wasn't interested in trying that except as a last resort.
The other day, after cleaning and refilling, I got an error message telling me that my black cartridge was no longer usable, and that continued use would possibly damage the printer. I purchased a new cartridge, and replaced. The old cartridge again had the buildup of ink on the bottom. So now I got the same "unusable" message, with recommendation that the cartridge be returned for replacement. And again, the bottom was loaded with ink. Obviously this was not just leakage from a faulty cartridge.
Information found on the web indicated that HP has only one repair location, and will not sell repair parts to even their dealers. Probable repair costs, added to shipping two ways, lead me to believe that I would be money ahead by either repairing it myself, or junking the printer. It has been in service (I am a retiree using it at home) for just over three years.
There should be information on this printer accessible on-line which is not included with their on-screen maintenance information:
I also referred to this document at a Sci.Electronics.Repair FAQ site.
I removed the cartridges, and stood them upright on a multi-thickness pad of paper towel that was moistened with distilled water (from dehumidifier), figuring that this might open any ink jets with dried ink in them. A flashlight helped to see the area at the far right of the printer, where the cartridges park. Those wipers were a real mess. The Q-tip swab technique proved quite unhandy, but with a larger wad of cotton on the tip of a long and narrow needle nose pliers, I was able to clean them. There is a well to the left of the wipers that appears to have a spongy material in it - well soaked with black ink. When I tried to clean it, it just depressed down into the well and stayed that way. The pads that rest against the cartridge bottoms when in the park position were inaccessible, as they retract when the carrier moves away.
The paper toweling soaked up a little ink (I had some plastic under it). I wiped the cartridge bottoms, then replaced them in the printer. Alignment worked well - no skips or smudges. But I kept getting the error message telling me to cancel printing and align whenever I started printing, until the computer had been shut down and restarted.
The printouts are now first class, and there are no more error messages. The "unusable" cartridges both work fine. Of course it has only been one day so far though!
(From: Someone who wishes to remain anonymous.)
I can only add that the cover comes off quite nicely by unscrewing the two screws found on the top of the printer toward the back and by wedging back with wads of folded paper the four plastic clips on the printer's bottom. With the cover off you have good access to the area that needs cleaning. Also, I used rubbing alcohol rather than water. The ink well is just that. There is no spongy material there. Mine was just full of waxy ink that had accumulated there over time. Needless to say, I dug that all out. Hopefully the printer should work well for another two or three years.
(From: Marc Geyskens mgeysken@innet.be).)
A while back, I got this broken down printer, most of the time the power supply wouldn't kick in after pressing the standby switch. After checking elementary things, I got stuck on the PCB that holds the standby switch, on it reside passive components, a few LM431 and a UN3854 all of the components where ok except for the LM and UN chips. Since I had no schematic and no sheet on the UN3854 I turned to the chip directory which led, via a few stops, to the Unitrode site and yes, a data sheet for the UN3851. Plugged my scope (power supply on isolation transformer) onto the ucc line for the UNxxxx, noticed that the voltage was almost 0 raising slowly to 12 V and then fast to 20V after that time the PS worked normal. So I traced the supply back to a FET 2SK537 on the power supply mainboard which is part of a protection, its gate pulled up by a zener ZD1 and a resistor of 680k from 400V and pulled down by a transistor in case of the transformer's output voltage gets to high. Well, it was the 680k resistor, infinitive resistance yet not a scratch on it.
Thanks to the Chipdir site, and the Unitrode people.
"My HP PaintJet printer has a problem! When I turn the printer on, the print head moves as if it's cleaning the head but thats it! The "on" light stays on but the "SET TOF", "LF", and "FF" buttons don't work. I've tried a test page by holding down the "FF" button and turning on the printer but it won't print. It just goes through the head cleaning stage again and then stops. If I turn the printer off and manually move the print head to the other end of the carriage and then turn it back on again the print head will move back to it's home position."
(Responses from: Paul Grohe (grohe@galaxy.nsc.com))
I am assuming you have the original tractor-feed "PaintJet", and not the sheet-feed 300XL.
It sounds like you have a problem with the "paper out" detector.
Is the second lamp on, even when there is paper loaded?
Here's a clue: If the other light is *on* after you do the self-test key sequence, then it thinks there is no paper loaded, so it does not print. The buttons are useless at this point, too. I have confirmed this with my PaintJet by removing the paper, and it does exactly what you describe. During normal "self test" printing, the paper out lamp is off.
It is very common with DeskJets and PaintJets to have their "paper out" detectors jam after rough handling.
Looking down into where the paper goes in, there is a little black lever sticking up (about 8cm to the right of the left end of the platen). This is the paper detect lever. The other end is a "flap" that goes between a photodetector.
Make sure this lever moves freely.
Open up the case (don't worry, it is very simple). Pull the big platen knob off. Then there are two rubber "wedges" stuck in two oval-ish latch holes on the bottom under the front "lip". Pull out the wedges and squeeze the latches. The cover then lifts right off (nothing is connected to it).
With the cover removed and viewing the printer from the front, look at the bottom left corner of the circuit board. You can see the "flap" end of the paper detect lever and photosensor, right above the "made in USA" sticker. Make sure it moves freely and that it is situated between the two detector "blocks" (I have seen these levers "wedge" themselves against the outside edge of the detector).
My guess is that you will either find paper jamming the lever, the lever itself mechanically jammed, or a piece of paper wedged in the sensor.
While you have the top off, notice that there is a long, plastic strip with fine lines on it running along the front. This is used for sensing the head position. Move the head over and make sure that strip is clean and that no ink has spilled anywhere on it. Also clean out any paper dust or spilled ink.
Don't be afraid to plug in the printer to test it with the cover off. The input voltage is only 20VAC, so you will not get shocked. Just be careful of the orientation of the power plug and watch out for the moving parts.
BTW1: The PaintJet printer is very stupid. It will 'print even with the cartridges removed or the platen motor unplugged, so there are no other sensors that could be causing a problem.
"The symptoms are that first the color cartridge got weak and stopped working and now the same has happened to the black cartridge. It's not out of ink or clogged and the contacts are all clean."
The 3630 (aka: "PaintJet") was one of, if not *the* first, color ink jet printer. As such, it was plagued by the usual "first-of-it's-kind" problems. HP learned from their mistakes on this one!
We have a few of them around here, and your experience is not unusual. They tend to "dry up" more often than the newer printers. I seriously doubt it is an electrical failure.
Even though the cartridge appears "full", the ink gallies will clog if not used after a certain amount of time. After a week or two, you will need to clean and prime the cartridges.
This printer does not have the automatic "priming" that the DeskJets have. Instead, you have to remove the cartridges and manually prime them with the "plunger" located under the "flap" on the top-left. Then "wipe" them with the rubber "nose-wiper" located on the underside of the cartridge access door.
There is (supposed to be) a slide-out card located on the bottom of the printer with the "cleaning and priming" instructions (The little tab with the "i" on it).
The PaintJet also lacks a rubber-sealed "cover" for the cartridge head when it is in the "park" position. This greatly adds to the "dry-out" problem.
The head connector also creates some problems. The 3930 uses two rows of individual long, gold-plated "fingers" to make contact with the cartridge. These "contacts" can bend back, or become mis-aligned, due to improper cartridge insertion or wear.
Take a look at these "fingers", and just make sure they are even and straight. Don't bend them too much, as they are brittle. Also make sure there is no leftover ink on the contacts. Don't press
It should be easy to fix. However, you may go bankrupt replacing the cartridges.
There are ink "refill" kits available, however, the problem is usually with the clogging of the internal passageways and jets. So new ink won't help much.
My suggestions:
Check the contact "fingers".
Try "priming" and "cleaning" the cartridges.
Try replacing the cartridges with known good ones (or new).
If you will not be using the cartridges for a while, remove them and place them in a sealed container or baggie for storage (place them in the same position as they are in the printer).
"What other printers are compatible with the PaintJet if I cannot get mine working and I need to use existing software"?
The "PaintJet" is a 180 DPI, "PCL" language printer. Just like the "newer" DeskJets.
If your unit has a parallel or serial interface, you can use any one of the older DeskJet printers (500/600 "C" series, DJ plus) - any that use the "PCL" language) or almost any laser printer (HPII compatible - B&W only). However, the newer printers are 300DPI printers, so the printouts will be 30-40% smaller.
If it is a HPIB interface, look for a HPIB ThinkJet.
(From: John Hudak (jhudak@sei.cmu.edu).)
Here are a few suggestions:
(From: Richard J. Scott (rjscott@telus.net).)
I have a Cannon BJC400 inkjet printer which I only use when I get home every week or so. Of course the ink clogs up the cartridge as always.
In my frustration, when I couldn't even blow the ink through this time, I took about 4 ounces of windshield washer fluid added about 1 ounce of isopropyl alcohol got it near boiling in the microwave and set the cartridge into it for about 1 hour. Bingo it came clean on blowing through the breather hole and printed beautifully. Nice cheap fix!!!
"I have a canon BJ330 that starts printing light and prints nothing. This only happens approx once every 2 months. The unit has ink and it still thinks it's printing but there is no ink on the paper. This has happened a couple of times and so far I haven't figured out what it is that I do to 'correct' the problem.I was thinking that there must be a way to clean the printhead that is not in the service manual. Which I do not have, anyway."
On my DeskJet, I just blow gently into the vent hole on the ink cartridge. I then wipe off blob of ink that forms on on the head and it works like a charm - if you don't get ink all over everything. Perhaps, try the following first:
(From: russrite@magmacom.com).
Remove the sponge from the purge cap carefully, try washing in water carefully, and reinstall it:
Take out the cartridge that you want cleaned. Find that hole that ink comes out of, squeeze the cartridge until ink comes out of that hole - actually drips. Put it back in the machine, clean it at least FOUR times. Usually on the fourth time for some reason, it works. Just clean the one that you think needs cleaning.
I have found that sometimes the BJC 600 series gets confused and needs to be reinitialized. If you haven't already done so, unplug it from the wall, wait 60 seconds for the internal supply capacitors to completely discharge, then plug it back in and try again. When you remove it from the AC line it goes through a complete warm up cycle and resets itself.
Also, the contacts that mate with the print head are notorious for oxidizing. You might want to carefully clean them (lightly) with a pencil eraser and some isopropyl.
If these remedies don't work, the Canon 1-800 number will put you in touch with their tech department, and they are really quite good at determining what the problem is over the phone.
(From: Al Savage (asavage@iname.com).)
When I was working on printers, we'd see a few of the 600s in with corrosion on the ribbon cable end under the printhead. NewKote apparently had a venting problem with their copykat ink cartridges, where in some situations ink would spurt (leak? drip?) and somehow corrode the ribbon cable.
I never tried to replace one and see if it could actually be repaired with just the cable, but I did try vigorously cleaning the cable end: no conclusive repair.
"Upon powering up the printer the two lights flash indicating a print head error. However by cleaning the electrical contacts (with alcohol) on both the print head and the printer the printer works,,, temporarily. Within a day or two the problem resurfaces. When the printer does print it prints excellent quality. The nozzles seem to be is good working order."
(From: Al Savage (asavage@iname.com).)
Although printhead failures are common on the 600 series, so is failure of the ribbon cable to the printhead. This is an acknowledged problem from Canon, when aftermarket ink reservoirs are used (i.e. Pirana or NewKote). Somehow the ink gets up to the cable/printhead interface and corrodes it. When I was working on them (about 18 months ago) Canon and NewKote were pointing fingers at each other. It appeared to be a reservoir venting problem.
"The error light on the Epson Stylus color IIs keeps blinking. The color cartridge is new. The black and white prints perfect."
(From: Robert J. Brancatelli (bronco@mkol2.dseg.ti.com).)
Most likely, the new color cartridge is not seating all the way. Move the print head to where you normally do to swap the heads. Now, without removing the color print head, lift the most forward lever up as far as it will go, then bring it down to reseat the ink cartridge.
The symptom is missing horizontal lines through text or graphics -- or no print at all. This occurs when the water based inks dry at the print heads in amounts that the head cleaning routine cannot dislodge.
The newer Epson Stylus Color series print heads are particularly affected.
It can happen whether you refill your inkjet cartridges or not.
One contributing factor is turning off the printer from a power bar. This prevents a complete shutdown and docking of the heads at their docking stations. You will notice some activity even after turning the printer off by its switch, as it continues to take a trickle charge.
To unclog the heads:
We've saved 14 printers this way.
I have an Epson Stylus Colour II printer which had similar problems- this time, which the magenta head.
After running about 50 cleaning cycles, and having no improvement, I disassembled the unit (I am WAY out of warranty already ;-) and manually mopped out the cleaning apparatus- the rubber heads were VERY gummed up, so I wipe them off... the suction tubes were clogged, so I squeezed them out, the sponges were full, so I mopped them up with a kleenex. I then put on a pair of elbow length kleenex gloves, and pulled the cotton cleaning tray/absorbent reservoir out of the base of the unit, and rung it out into the toilet. There was a three year accumulation of wasted ink in there- this printer gets extremely heavy use, but it was amazing at the amount of ink that gets wasted, compared to what goes on paper! I would guess that it's about 30/70, 70% ending up on paper. Incredible wastage. I just don't buy cheap refills. I buy better ones with guarantees on them. I also replace the cartridges that I am refilling every four to six refills. There will be an accumulation of 'junk' if you don't.
The cure to my problem? Pay the price for the genuine epson cartridge and do another fifty cleaning cycles. It worked for me. I had to wring out that @#$%liner again....
(BTW, If anyone else has an epson inkjet, I recommend that they get the liner replaced or at least wrung out. It's a horrible mess which can overflow if you use an awful lot of ink... mine was saturated... you may have a nasty surprise next time you decide to move the printer- all down the front of your shirt. ;-)
"I have an Epson Stylus 800 printer which is only used infrequently. I seem to have a problem with some of the jets clogging up after a while producing a banding effect and/or a blurring of text.The built in cleaning cycle does not clear the problem. Running the head over a pad soaked in Isopropyl Alcohol clears the problem, but after a week or so things start getting bad again.
The user manual does not mention the need to change any cleaning pads. How does the cleaning cycle work and are there any checks or adjustments which might improve things?"
(From: Paul Grohe (grohe@galaxy.nsc.com).)
Inkjet printers do not like 'infrequent' use. They need to be 'exercised' every once and a while. Use 'em or loose 'em!
I'm not familiar with the Epson products, but on the HP DeskJets, there is a little rubber "seat" that the cartridge sits on when it is 'parked'. If it is gummed-up or damaged, it can cause the cartridge to slowly dry out.
The HP's have a little oval-shaped rubber 'do-hikey' that seals the area around the ink jets. It generally gets gummed up with dry ink, and does not seal completely anymore.
Check and see if there is something similar that covers the print head when it is not in use.
The "banding" can also occur as the cartridge starts getting towards the end of it's life. Also try cleaning the contact areas with a soft cloth. Poor contacts can cause similar problems.
If large ink droplets are forming on the head during printing, this is a sign of poor contacts or a physically damaged head.
However, most of the time it is caused by "clots" in the areas supplying the jets, or in the jets themselves. Sometimes soaking the jets in a tray of alcohol or water for a while can dissolve these "clots", but the success rate is not that great. Better to fix the root of the problem.
BTW: Avoid turning the cartridge upside-down. Always hold it so gravity pulls the ink down to the jets and keeps them primed. Turning it upside-down can allow air to be drawn back into the jets.
Then again, it may be time for a new cartridge!
Sorry to be the bearer of bad news, but the both the purge pump and the printhead in the Stylus series (300, 400, 800, ColorII) are very trouble prone. I've scrapped a couple dozen of them. The cost of a replacement printhead is more than the printer on sale.
They do print nicely when they're working, though. My experience is that they don't work for very long.
PROBLEM: Dryed black ink clog-up in the tube leading from the black ink cartridge to the print head. Black ink flow totally halted. New cartridges won't work.
BACKGROUND: Epson uses very fast-drying, water-soluble, inks in this printer, and if the printer sits idle for some length of time the ink feed tubes and the print heads become clogged with dry ink. Epson issues dire warnings about potential damage to the printer if attempts are made to flush these parts with any solvent, and recommends factory repair only.
On the advice of someone who has vast experience with such problems, I successfully used the following repair. procedure.
REPAIR PROCEDURE: Use a clean small hypodermic syringe with NO needle. Press on to the syringe nozzle, a 3/4 inch long piece of model airplane gas engine fuel tubing. This tubing is available cheaply from your local model hobby shop. It is a pale light blue colored plastic tubing. The MEDIUM size is the right one. The bore (ID) of the tubing is less than 1/16 of an inch. It makes a very tight fit when pushed onto the syringe nozzle.
Remove the cartridge from the printer, and pull the power plug immediately to prevent any further printer movement.
Load the syringe with 2-3 CC's of scalding hot water, preferably distilled water available at your grocery store. Then press the other end of the tubing down over the little black nozzle in the bottom of the cartridge holder. It must be a very tight fit.
Forcibly inject the hot water into the printer. If the clogging is really severe, you may have to press the syringe plunger very hard. Continue injecting until the syringe is empty, while making sure that the tubing does not slip off the syringe or the printer nozzle. Repeat this injection procedure 1-2 more times with more hot water if necessary.
Once the hot water goes through easily, the clog has been dissolved. It may be necessary to wait 24 hours for the water to evaporate, but in my case it was not. I simply replaced the black ink cartridge, and ran the Epson's head-cleaning utility several times until the black ink started coming through. Running the nozzle-check utility, to make a test pattern print, will let you know when the ink flow is OK.
This same procedure should work equally well for the colored inks of this printer. I suspect that the procedure will also probably work for some other Epson inkjet printers as well.
Use this procedure at your own risk. All I can tell you is that it worked beautifully for me. There was NO printer damage.
The people who talk about clogging, etc. must have never seen a BJC-620, in which the printhead and ink tanks are separate. I've had a 620 for about 16 months and having printed almost nothing on it (have a laser for most needs) have noticed that the ink tanks last about 5 months. My third set of cartridges at $40 per set have just recently gone dry. (Actually only the color ones are dry. The larger black one lasts longer.) I foolishly threw away the first set of empties, but I still have two sets. I decided that I've sent enough money to Canon and searched the web for a more economical solution. What I found was Bob Nedved and his re.ink.kit refill kit at:
where, for $74.50 I got an amount of bulk ink equivalent to about $800 worth of new cartridges. Included also are 4 syringes and 4 small screws. The procedure is to make a small hole in each tank tank and seal it with a screw. To refill, you remove the screw, inject a few cc of ink, replace the screw, and clean the syringe with a little alcohol or distilled water. Filling the first cartridge was a little messy, but once you get the hang of it, it's a snap. The kit doesn't completely eliminate buying new tanks, because the tanks themselves eventually need to be replaced, but it sure does cut the annual maintenance cost, whether you only use the printer a little or if you use it a lot.
(From: Bill Sloman (sloman@sci.kun.nl).)
Epson uses a piezo-electric print head, and an alcohol-based ink. If you don't like paying for Epson's ink cartridges, use Pelikan's (I think that is the brand I use - it is certainly one of the old-fashioned ink manufacturers). They seem to use a higher molecular weight alcohol than Epson, so the cartridges last me more like six months than three in the old (1993) Epson Stylus Q800.
HP and Canon use a water-based ink, that is actually heated to boiling in the print-head to spit out droplets - so the print head corrodes rapidly, which is why their "ink cartridges" contain an new print-head and only about 15 ml ink, as much as the print-head can reliably spit out.
Having worked at Epson, Canon, and HP warranty service centers, I tell anyone who asks me for advice about buying an ink jet printer to always choose one where getting more ink also gets you a fresh printhead. The number one service problem with all inkjets is printhead clogging failures. On the Stylus 800 series, for example, the printhead retail cost was $170, and the labor was about half an hour. On the Canon BJC-600, the P/H cost was $250, but the head could be changed by the owner. And with so many folks using third party ink that works like it was brewed up in someone's bathtub (NuKote, Piranha (sp?), etc.), printhead failures scrapped more inkjets than any other three causes combined.
Cheap, owner-replaceable printheads help keep cheap inkjet printers out of the landfill.
(From: Roger Hamlett (roger@ttelmah.demon.co.uk).)
I disagree with the comments about chosing one where getting ink gets you a printhead. I have a bin full of 'dead' HP cartridges, that have resisted various attempts to get them printing again, yet also have an Epson here, that is four years old, and has never given any problems. The bill for cartridges on the HP, (allowing for the part use), would have paid to replace the printer a couple of times over.
One other thing about HP inkjet printers (DJ 550, 560, 850): Before you buy an ink cartridge, look at the expiration date on the box. Don't buy it unless you expect to use it before the printed date. That number really means that the cartridge will NOT work after the date...no matter how it is stored. Water and/or hot water rejuvenation rarely works on cartridges that are outdated. The reservoir evidently turns to crap and won't wick the water in or the ink out.
(From: Jim Steel (procomputer@telisphere.com).)
Repair instructions.
The power supply is encased in a bonded 2-piece ABS plastic housing. There is a fuse inside but no way to access the fuse without splitting the case.
Splitting the case:
Unplug the power supply and secure the power supply in a utility vice. Use a short-blade utility knife or linoleum knife to slowly and carefully and cut along the seam where the 2 halves of the power supply are joined. Don't try to cut the seam all at once. Work a little at a time until the case halves can be separated.
Replacing the fuse:
On a power supply with an unsoldered fuse socket, simply replace the fuse and test the power supply. Alternately, a leaded fuse may be soldered in.
On a power supply with the fuse soldered into the fuse socket, leave the fuse in the socket and solder in a leaded fuse. (A leaded fuse has lead wires extending from each end of the fuse.)
On a power supply with a leaded fuse, unsolder the old fuse solder in a new leaded fuse.
Testing the power supply:
Ensure that the power supply and printer work before bothering to close the case.
Closing the case:
ABS plastic cement may be used to bond the power supply case halves. Alternately, electrical tape may be used to hold the case halves together.
Note: also see the chapter on Photocopiers as the operation and problems of the two types of equipment are very similar.
While this doesn't have much electronic repair information, it certainly would seem to cover just about everything else including some discussion of common image quality and mechanical problems. Note that this on-line book was present awhile back and disappeared. Now it's back but for how long, I have no idea. So, download what you need and save it!
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
Firstly the health/safety warning. Toner, because it's a very fine powder, is (a) carcinogenic, and (b) explosive. However, provided you don't make clouds of the stuff, you should be OK. It can't be *that* harmful, as some photocopiers take 'loose' toner, and some printers have separate toner/drum/waste toner units.
I've fixed mechanical problems on the SX and CX cartridges. I also once moved a good drum from an empty cartridge to an almost-new cartridge with a scored drum (don't ask...).
There are 2 things you need to do to refill one - empty out the waste toner tank and (obviously) add some new toner.
The SX cartridge is easy to dismantle. Unclip a little triangular plate on the side, pull out 4 plastic pegs, and the case comes off. The plastic bung for filling the toner tank is obvious. To empty the waste toner, you have to take the cartridge apart, remove a plate (2 screws) and empty the toner into something. I worked inside a plastic bag last time I opened one of these cartridges.
These printers use a combined toner and developer. The toner mix must be magnetic for the printer to work at all.
I've seen bottles of loose toner for some photocopiers. I have not idea which brands would be suitable (if any), but I might experiment sometime.
As for inspection/testing:
Well, the main test is probably drum sensitivity (but this won't change unless you are swaping drums). Now, if you get that wrong, all that happens is that the image is too light or too dark. There are some little plastic clips on the side of the cartridge that operate microswitches in the printer. And there are only 3 settings!. Believe it or not, I've found some remanufactured cartridges that work better when these blocks have been moved - in other words, the drum sensitivity wasn't checked properly.
Everything else should be mechanical inspection - condition of bearings/gears, leaks, primary corona, etc. Nothing that's impossible to do at home. Of course it's rather different if you're selling remanufactured cartridges - in that case you need to be sure the parts will last another 4000 pages or whatever. But if you're fixing up your own printer, and don't care if you have to fiddle with something else in 1000 pages time, then there's no real problem.
About the worse that can happen to the printer is that the cartridge dumps toner all over the insides. I've had that happen - once. And it wasn't from a cartridge that I'd had in bits. It was from a remanufactured cartridge. That, together with the incident where a CX cartridge had had the door assembly incorrectly assembled, which caused damage to the transfer corona assembly, convinced me to avoid remanufactured cartridges that I'd not rebuilt myself, or at least checked.
You do need to avoid mixing waste toner (which will probably have a higher concentration of developer) with the new toner. Empty out the waste toner tank, but don't add the contents to the new toner. But if the toner you are adding is similar (or better still the same) as the original stuff, there is no problem from the residual toner in the cartridge.
Plenty of printers (Ricoh engine?) use 'loose' toner + drum/belt as separate parts. In those, you do add new toner on top of the old, and it all mixes up. Now, why should Canon printers be so different?
(From: David H. (textool@aol.com).)
It's always a good idea to clean the entire optical path from the laser (diode) forward. Most of this is inside the scanner module and there may also be a long external mirror.
With time these surfaces become coated with a film of toner/dirt and the laser beam reaching the drum gets weaker and diffused. Print quality suffers and later "beam detect" or "scanner failure" errors will occur, which may be intermittent at first, but eventually they will shut the printer down completely.
So open up the scanner module and gently clean all the prisms, mirrors and lenses. I say gently because the mirrors are front coated and the lenses may be plastic which can be scratched by aggressive cleaning with cotton swabs. Clean the external mirror if there is one. There is also a beam detection sensor which will have it's own small lens or prism which must be cleaned. Good luck.
In my experience dirty optics has been the they most common failure in 4+ year old laser printers with Canon engines.
Yes, with extended exposure. I remanufacture toner cartridges for a time. Long term exposure to light will effect the photoconductive layer. We even cover areas of some (scratched) after-market drums and exposed them to sunlight to see how it effected them. It takes extended exposure to show an effect. No, the printer will not detect the problem and the printer will probably print dark for the basic 'positive' image (a dark area is exposed to light) laser printer. A scanner or copier might print light (reflective light of the 'white' surface exposes the surface of the drum. Good Luck.
Depending on where the problem originates, this could be a bad wiper (cleaning) blade, faulty corona, or incomplete fusing.
A residual latent image or residual toner is sticking to the drum and not being properly cleared.
It is easy to determine where the problem is located: Interrupt a printout in mid-stride (where part of the paper is between the toner/developer and fuser. If the un-fused image has ghosting, it is a fault in the area of the drum. Also see the section: Previous copy doesn't erase from drum.
90% of the time it is the toner cartridge (or drum), If it is still exactly the same condition with the new cartridge, here is one exception: The fuser assembly has a rubber roller, I had one with an indentation in one spot, allowing toner to pack in the indentation & actually transfer a small character impression onto the fuser roller and then transfer it to the paper several times on each sheet. The fuser is very easy to remove(2 screws at the back). I temporarily worked the indent out of the soft rubber, but eventually replaced the fuser assembly.
(From: Dave Lee (leedj@uwec.edu).)
According to "Image Defects, Repetitive image defect ruler in LJ4", the cause would me the "Primary Charging Roller", is 1.5 inches or 38 mm around. Start with that, swap with another printer is possible, or order one, try Parts Now, Inc, 800/886-6688 or The Printer Works, 800/235-6116 or Global Printer Service, 800/588-3554.
"I would like to remove the mirror in order to clean it well. It mounts on a plastic bar that runs the width of the printer. The bar mounts by screws (2) at either end. I am worried that I will need some kind of aligning jig to get it back properly."
The short answer is: DON'T. Some aspects of the alignment are impossible to adjust/correct/reinstall without factory jigs and test equipment. The best you can hope for at home is trial-and-error. Most of the optics is probably solidly glued in place anyhow so disassembly is difficult or impossible - but it doesn't move much either! The long mirror itself is probably less critical than the rest but there is no real need to disturb it.
To clean the optics, use (low pressure) compressed air, alcohol and lens tissue, or as a last resort, alcohol and cotton swabs (Q-tips). However, some lens and mirror coatings may be easily damaged - test in a corner first.
(From: Pete (PTCull@lbl.gov).)
You are correct in being worried. Alignment marks closest to the muffin fan side of the engine should be noted before removal of the Beam-to-Drum Assembly. Better yet, just blow the mirror clean with a filtered compressed air source, leaving the mirror mounted.
Unless the mirror is very contaminated, I really wonder if you'll see the improvement you believe you might? Some of these mirrors have very soft surfaces and only should be touched with lens cleaner or cotton swabs.
If you still choose to remove the mirror from the engine, check to see if the two extreme sides of the page seem even when referenced to the top edge, using the "Engine Test print".
I used to fix lots and lots of HP II and HP III here in Brazil. So, with time, I developed a "checklist" for HP II and III repairing, that is safe enough to keep the printer working for years (4 years and NO defects whatsoever) and customers were happy. I'll include things not necessary for Americans (Brazil is HOT. Hotter than USA!) because friends all over the world may need this info.
What you need: Isopropyl alcohol, toner sucker, good screwdrivers, cotton, cotton swabs, screw picker (that little handy tool to pick/put screws in tight places), some rags - and lots of space!
I'll take the HP III as an example, The HP II is equal, with very minor differences. Please apologize me for any incorrections, since I'm telling everything from memory.
Well, this completes my "HP Refurbishing method". To reassemble it, you do the following:
And so you have a healthy HP III. It will last for YEARS if you did it right. don'ts forget to put a fresh new cart of toner and it will last forever. Of course, you want to clean everything externally too.
The common disclaimers apply here. Do it at your own risk. I've fixed some 500 HP LaserJet IIs and IIIs, and never had a problem, return or anything doing that. Your mileage may vary. Greetings for Brazilian friends, and for all around the world that uses that guide. :o)
I fell in love with this printer but this puppy got some Coke in her fuser and messed things a little. So I was obligated to do a complete disassembly of it, to clean up the mess and change a gear. So, here we go:
To disassemble the fuser:
This is my method of "Refurbishing" the HP4+. Note I have one with 400,000 pages printed and NO problems. The gear I changed was INTACT (as the others on the main gear module) with only 2 broken teeth caused by the roller, that was completely locked!!! It was SO Glued with coke that a small gear on the fuser, after unassembling, was completely unable to move, before taking it out with great force, and cleaning with alcohol. After that, it was free as a bird. Go figure...
Just a little fun: This one cost US$30. :o) Spent more US$40 to fix. The parts were more expensive than the printer itself he he he :o)
There's a very quick test for the erase lamps in these printers (SX engine). Open the cover, and swing it right open. There's a plastic post that comes down from the cover at the back left with 2 contacts in it. It goes into a slot on the left side of the fuser when the printer is closed.
Check for continuity between the 2 contacts in the cover. I have no idea what the right resistance would be, but it's less than 1k. If it's open-circuit then most likely one of the lamps is burnt out. There are 5 of them, in series.
If the lamps are good and there are still erase lamp problems, then remove the fuser, take the cover off the left side of it (1 screw on top) and unscrew the PCB under it. Check the 2SD1414 power transistor Q331 on this board (it's the erase lamp driver). If that doesn't do it, check the components around it. R335 (1.8 Ohm) is the current sense resistor in Q331's emitter circuit, L331 is a filter choke in series with the lamp supply, and Q331 is a current sense transistor that removes the base drive from Q331 if the thing overcurrents.
I suppose it could be a problem with the cable back to the DC controller or even the DC controller itself, but that's unlikely.
If you've still not found the problem, though, post again and I'll think again.
"On self-test, pulls in paper, pauses, indicates "51 err." Then pulls paper through mechanism while "02 warming up" is displayed. Nothing prints, except for 2 horizontal black bars about an inch apart with grey in between them, about 1/3 from top of page. Since we stole this fair and square, and since we have a number of good (but _not_ laser printer) techs around, I'm wondering where we might dig. The book simply says error 51 means we should call HP service."
(Note: In the discussion below, the specific cable and parts IDs may not match your model.)
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
It's called a 'beam detect error'. Let me explain what that means:
The laser beam is reflected off a spinning hexagonal (I think) mirror, and scanned across the drum. At one end of the scan the laser is turned on, and the reflected beam hits a fixed mirror (not the drum) and is reflected down an optical fiber to a photodiode on the DC controller board. The electronics on that board detects the pulse from that photodiode and provides a sync signal for the data sent to the laser
So the fault can be the laser, the scanner motor, assorted optical bits, the photodiode, or bits on the DC controller board. I think we can eliminate the motor for the moment, as that tends to give Error 52s.
Look at the PrinterWorks Web site (http://www.printerworks.com/) for exploded diagrams. Also read the section: SAFETY since you will be inside the printer near high voltage and possible exposure to laser light.
The official fix is to replace the scanner, the cables (electrical and fiber optic) between the scanner and the DC controller, and then the DC controller until the fault goes away. But you can often fix things
Start by pulling the casing. Over the paper tray there's a flat black box. Start be reseating the 2 cables (one under the flap) that go to this unit.
If you have an IR detector (as used for testing remote controls) then undo the screw on the scanner - not the fixing screws that hold the scanner in place - remove the grey optical fiber, and hold the sensor over the channel that the fiber fitted in to. Do not look up this channel - it can output laser light. Turn on, and try to print a test page - which will fail.
If you get IR light out of the scanner unit:
Reconnect the fiber at that end, remove the base of the printer, and arrange some way to prop it upright with the interlock switch pressed in. Unplug the fiber from J201 (a DNP-like connector) on the DC controller board. Put your IR sensor on the end of that and test again. No IR light now, time to replace the fiber.
Reconnect the fiber to J201 and hook a logic probe or 'scope to TP208 on the DC controller. This is the output of the photodiode amplifier. Do you get pulses here? If not, check the photodiode and the transistors Q202, Q204, Q208. If you do, then, alas the problem is most likely in a custom chip, and it's time to replace the DC controller.
If you get no light from the scanner, then it's time to inspect it:
Carefully trim back the moulded clips that hold the cover on the scanner and open it up. Clean the optics with a soft brush or lens tissue. The mirrors are front-silvered of course. There's a little shutter in the laser beam, opened when a toner cartridge is locked in place - is this opening correctly when you close the printer? If not, find out why not.
Unplug the cable from the laser PCB, power up the printer and try a test page. Does the scanner motor rotate? If not, we'll debug that.
The last possibility is that the laser isn't coming on for some reason. Debugging that is going to be interesting (read Sam's laser diode notes next :-), and I'll do the same) and I'll try to talk you through that when I know it's necessary. (Note: Sam's laser diode notes -- Diode Laser chapter of Sam's Laser FAQ.)
(From: Tom Dunn (dunnt@cco.caltech.edu).)
Error code 51 indicates loss of laser beam for over 2 seconds. Check -5 V, also make sure there is no interlock mechanism damage, and +5 V at J451-1 on Laser Drive PCA. You may need new laser unit. Good hunting.
(From: John Holcepl (john_holcepl@nls.net).)
This is a very common error on a HP Series II. An error code 51 is loss of beam detect. The cause is a bad cable between the DC Controller and the laser/scanner assy. P/N RG1-0908-000CN. Sometimes just reseating the cable will make this error go away but it will come back eventually.
(From: Eric Liber (liberes@westinghouse.com).)
Here is the description of the possible 51 errors:
51 ERROR (Loss of Beam Detect)
What you need to do (if you're going to remove the whole assembly) is to remove the (brown) cover that's flat on the printer chassis just behind the 'tower' at the front that contains the interlock switch and AC control boards (where you removed the fuser heater wires from). Under that cover there's a little 4-way connector that links the fuser thermistor back to the engine control PCB (DC controller). Unplug that.
Then you can remove the 4 screws that hold the fuser in place, lift it up a bit, and free the heater wiring from the channel in the baseplate. The whole fuser then comes out.
These fusers can be stripped and rebuilt - I've done it. If the old one still heats up, keep it for the heater lamp that's in it - that lamp does fail, and it's not that hard to replace. It's a quartz-halogen bulb, so you shouldn't touch the 'glass'. The safest place to store it is in the old fuser.
These printers are that bad. I've had one stripped down to individual components (even dismantled the optical assembly), and have it running now. But the SX engine (LJ2, etc) are a lot easier to dismantle into modules (and in some cases harder to replace individual components on...)
"Got one that started making unpleasant noises about two weeks ago. It is in a church office environment, so they have to turn it off unless they need it for a short while. I took part of the cover off and decided it wasn't the top fan or the small motor on the right side. The sound comes from the right rear at the grilles at the bottom of the machine. It sounds like a bad bearing or something rubbing a fan."
(From: Ralph Wade Phillips (ralphp@techie.com).)
Bad lower fan. Part number RH7-1056. I'd check at http://www.pcservice.com and register and order XX-RH7-1056 (it's under $20) and just replace that fan.
I'd also consider replacing the upper fan (go look for it with the search engine - it's about the same $ for the generic 3rd party version) since a failure there will ALSO cost you the fuser gears, thereby costing a fuser assembly.
As to removing the bottom cover - Eh? Put the top back on, flip it over, and remove those screws you see around the rim. Remove all cartridges also. Slip the metal cover off, and viola - There she is!
Big warning - Do NOT run the machine with the lower fan disconnected. This is
known to damage the DC controller board (at least a $60 part, EXCHANGE - over
$300 purchase!), and can cause massive problems later down the road ...
(From: Al Savage (asavage@iname.com).)
Probably the most-commonly-replaced part is the lower fan on the 33440A. Yes,
it's very noisy when bad, right up until it becomes extremely quiet
Well, buying 10 year old hardware and then wanting to depend on it not
breaking isn't very realistic. As reliable as the LJII/III is, they DO break,
especially lower fans, the 14T fuser gear, paper pickup roller, pickup
photosensor, AC power supply, registration assy. It's just that they'll
commonly print half a million pages in the process, and many contemporary
printers aren't designed for a service life a third as long.
To replace the lower fan, have a vacuum cleaner with a brush handy (or an air
compressor). Remove toner cartridge/drum unit. Close lid, remove all cables
(power, data), flip printer upside down. On a LJII, you're looking at steel
square pan; on a LJIII, you're looking at a large plastic tray and you have to
remove four Phillips-head screws to get it off first.
On both models: remove any optional memory card(s) by first removing the
access hatch for them on the left side. This hatch is the one *without* the
1/4" hole in it. Remove any circuit board you find under there: they just
pull straight out.
On the back of the printer, remove any optional I/O card (HP JetDirect,
Appletalk, etc) that may be installed next to the normal Centronics data port.
This isn't always *necessary* but when it isn't it just makes things easier.
Once again, just remove two screws and pull on the I/O card.
Now you can remove the lower pan. Nine Phillips head screws later, lift the
front edge of the pan, wiggle it to get it off over the Centronics port cable
clips.
Vacuum the pan out -- it will be filled with dust bunnies -- and any dust you
see collected on the mainboard. You can now see the lower fan. It's a
squirrel cage design. Remove the short wire harness and the four screws to
remove it. Note the position of the small bracket under two of the screws, as
you will need to put that bracket back!
Reassemble in reverse order. One screw on the lower pan does NOT go in the
left rear corner, but that's only a problem is you have the upper plastic off
as well. You can't put it in wrong if the upper half is still assembled.
The fan is about $20 wholesale, often close to $40 retail. Do NOT attempt to
disassemble and clean it. I've tried several times, and no matter what I try
it will either still be noisy, or will fail again within months.
Check the daughter board in the PSU at fault. On mine it had deteriorated
solder connections on *both* ends of the connecting pins. Remove it, resolder
the pins on the daughter board, then remount it. It's worked like a charm ever
since.
I have a LJ II that has the following problem:
Swapping cartridges has no effect."
The problem turned out to be the chassis wiring harness from the DCA
controller to the HV module. There was a bad connection between the HV module
and the chassis connector only when the module was inserted. I ended up
extracting and soldering all the crimped pins in the connector. I suspect that
it was probably the HV reset line that was the problem.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
I think you've got 2 problems here - the false paper jam with the tray open,
and a problem with the drive to the top rollers.
Let's look a them in that order.
There's only one paper sensor in the SX engine that I know about, and that's
part of the fuser. On the PCB at the left side of the fuser there's a slotted
opto-switch with a lever that detects paper in the fuser. There's also a single
transistor on said PCB that buffers/amplifies the output from the opto-switch,
Q332, I think. This sensor must change state one way (to indicate paper has
got to the fuser) shortly after the registration clutch operates and then
change state the other way when the paper has got out of the fuser.
You might start by reseating the cable at J206 of the DC controller board
(just in case it's bad connections) and then look at the sensor (mechanically
and electrically) on the fuser PCB.
Silly question: If the paper tray switches (on the DC controller board) aren't
operating properly, could the printer think it was feeding a shorter piece of
paper than it actually has, and then give a paper jam error? It's always
possible... Alas I don't know the coding for these 3 switches (SW201-SW203)
The other problem is almost certainly mechanical. Look at the gears on the
right hand side of the fuser (stripped teeth do occur here) and in the top
cover of the printer. Shouldn't be too hard to find where the drive has
failed. I suppose you could remove the outer casing and AC block, re-insert
the fuser and close the cover, and look at things while turning the machine by
hand.
Can someone tell me how to test the DC controller to see if it is
defective or maybe shed a little light on what may be causing the unit
not to make it to the "ready" mode?"
Any number of simple faults can result in the warmup sequence not completing.
Check these first before suspecting a blown power supply or controller.
It may indeed be as simple as a burned out bulb or broken door interlock.
(From: Dave Lee (leedj@uwec.edu).)
Here is what I found in my notes concerning your very same problem, Hope it
helps......
New "Service Today" from Parts Now, volume IV, number 1, issued in
Feb 95 is devoted to the "LX" engine units, IIP/IIP Plus/IIIP Series,
the Cannon LBP-4, Apple Personal LaserWriter. Lots of good stuff, error
50's, error 41's, fuser upgrades, "moaning", other squeaks etc.
Here is what it says:
(From: Jeff Churchvara (jeffc@pond.com).)
Experience would have diagnosed this one in about 10 seconds. I just
didn't know what I was looking at.
I started reading the FAQ and figured the worst. At first, I did not
have the service manual to go over this code. When I finally did get a
copy, I started checking the voltages and did not have +24 V at the DC
Controller PCA.
All of what I was reading said to defeat the door interlock. At first,
this didn't make sense to me because the bar that should be attached
to the door was instead, laying on top of the switch and wasn't even
moving when the door opened. I didn't know enough not to look any
further.
Once I realized the bar should've been attached to the door, I started
looking for it's correct mounting. The screw holding the bar must have
loosened up and over time it broke the mounting nut right out of the
door.
I ended up resetting the nut (threaded sleeve) by adding a screw from
the outside. Then I pinched it in place with a second screw when I
re-anchored the bar. This made the bar pull away when the door opened
and then correctly contact the interlock switch when the door closed.
I forgot the basics of troubleshooting when I posted this one and was
making it more difficult than it actually was.
Thanks to all of you who responded and kept me looking in the right
direction.
Check to see if the image of the printout to be, is on the image drum. If it
is there and isn't being transfered to the paper then something like the high
voltage corona wire or hight voltage supply isn't charging the paper.
(From: FAXFIXR (justdfax@cdepot.net).)
There are two corona wires, the charge corona and the transfer corona. The
charge corona is the one you should look at. It is located in the toner
cartridge so the easiest way to check is try another cartridge, even one
that is out (or almost) of toner. If you don't have another, then you can
check yours. If you look at the cartridge in it's operating position, there
is a black mylar plastic film that covers a slit on top from end to end.
The mylar covers the corona wire but allows you to insert the little green
tool, found inside the copier, to wipe the corona. If the tool is there,
stick the pad into the slot and wipe it back and forth. If you hear a
slight screeching sound (like a violin) then the corona is there. If it's
not there, then the cartridge must be replaced.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
(The following was written for HP LaserJet III but it is generally applicable
to other laser printers and photocopiers.)
For starters, try a new toner cartridge. I've found these can cause
all sorts of problems...
Now, blank pages are due to one or more of :
Start it printing a test page (the 'engine test' switch on the DC
controller is useful for this). When the paper is still going through the
printer, turn it off, open the lid and pull back the cover over the drum
in the cartridge. Is there a 'latent image' on the drum? If so, check the
EHT power supply and transfer corona assemblies.
Check that you plugged the cables into the scanner properly. They don't
always make good contact. This will normally cause a 'beam detect'
problem - I forget what the error is for that (51? 52?). It's possible
that there's an O/C in the cable, of course.
If you have an IR detector (of the type used for testing remote
controls), unplug the optical fibre from the DC controller and point the
end at the IR detector. Again print a test page. If the laser and scanner
are working, you'll get some IR (laser light, so take care) out of the
end of the fibre.
There is a mechanical shutter in front of the laser in the scanner that's
opened by a lever under the scanner when the cover is closed with a toner
cartridge in place. The idea is to prevent any laser light getting out if
the printer is run with the cover open/no cartridge. Is this working
correctly. Did you get the scanner correctly on top of it.
My (donated) Laserjet II series printed black horizontal lines after about
the third sheet. It then occasionally spit out "error 41".
Solution:
The ball bearings of the scanner unit were defective (now I know that my
printer was MUCH louder than other HP 2s).
That caused the scanner unit to get "out of sync" and print black lines and
occasionally spit out "error 41".
I just replaced the ball bearings and everything was fine again.
As far as I know, no Laserjet error codes service page mentions this yet.
(They only say that "the scanner unit may be defective", but not HOW that
may be.)
I had a LaserJet series II with exactly the same symptoms: 50 SERVICE and
that very clicking sound. I fixed that printer last week after quite a bit of
troubleshooting.
First: the clicking sound comes from a mechanical relay in the PSU, which
controls, together with an SCR solid-state relay, the sequence in which
power is applied to the heating lamp in the fuser. The sound itself is not a
problem, it is a symptom. You probably have a bad thermistor in the fuser
assembly, or the signal path from the thermistor to the control board is
corrupted.
If you are good with electronic troubleshooting, try the following:
(From: Mark Wolfe (markw@wwa.com).)
Just to speed things up a little, override the printer open switch, and remove
the plastic cover from the right end of the fuser to get at the power
connector for the bulb. Turn the thing on, and read this connector, should
see about 115 VAC, if you don't, check Q101 in the Power Supply. The problem
you had sounded like a rarity, as it's usually the halogen light in the fuser,
or Q101 in the power supply. Yours was the sensors going back to control
Q101. Anyway, if you ever have one of the power supplies opened, it looks as
if HP intended this triac to fail with it's whimpy heat sink. Hope this helps.
I had the same thing happen to me on a IID, check the connections on
the fuser. I swapped fusers with my III, and both printers worked,
swapped them back and both printers worked. The power connector on
the right end of the fuser seemed a bit loose, could've had a bad
connection. Anyway, IID is still going, and this was in august when
I did this.
(From: Chris Holmes (holmesc@sedgehill.lewisham.sch.uk).)
I dont know if Error code 50 is the same as Service 50 on the HP Laserjet II
but if it is you are in luck.
I once had this and spent about an hour and a half stripping cleaning
and reassembling it, and it worked! When I got back to civilisation I
checked the manual. The official HP action for Service 50 is - switch
off for 10 Mins!
Still i'm sure the clean did it good.
(From: Frank Reid (reid@indiana.edu))
A fuser-heating fault in HP Laserjet II or III (or the Apple equivalent)
causes a capacitor on the dc controller board to charge. Discharge takes
10 to 30 minutes. If you repair the problem and restart the machine before
the capacitor discharges, the error indication remains.
(From: Stuart Elflett (stuarte@OntheNet.com.au).)
Does the 50 error now stay on constantly, e.g. if you turn the machine
on after a 30 minute wait, does it still say 50 error without doing
its self test?? If so, I'd head towards the D.C. Controller. If the
bulb in the fuser comes straight on, and the delivery rollers don't
turn a little before hand, I'd be looking at the AC Supply. Is your
fan spinning?? A stalled fan can often result in a 50 error. Is the
fuser heating up?? If you're technically minded, you could remove the
fuser and check the bulb for continuity.
Parts are commonly available almost world wide now.... you could check
my links page for some sites that provide parts.... there's plenty
more out there that aren't on my list..... try a web search for Laser
Printer Parts....... They're not too expensive, as long as you get
exchange parts where possible!! A manual would be a good purchase if
you intend doing the work yourself, however they are still relatively
expensive compared to parts!!
(From: David Gardner (gardneda@www.gc.cc.fl.us).)
Error 50 is called a fuser error, which it is, but I have found that it can
also be caused by a bad High Voltage power supply or by a bad cable that runs
from the power supply to the fuser.
When confronted with a code 50 - after checking lamp, lower fan operation,
thermal cutoff, wire connections etc. I always, as a precaution against
call-backs, 1. remove solder from wire ends at thermistor, clean and resolder
with silver solder, 2. replace 1k ohm resistor under pin connector (thermal
protector board on end of fusing unit), 3. replace Q101 (triac on power
supply board ) and add more heat sink, 4. replace D155 on dc control board. 5.
restake all wire end connectors with stake type wire connections. All of
these are prone to happen and you can cut them off at the pass by taking care
of these common offenders while you have the machine open. The voice of
experience, I hate call backs!
Problem: In multipage printing, the first page will print fine. But, the top
line of the second and subsequent pages will be shifted about 1/2".
Cause: There is a solenoid on the right side of the printer which stops the
toothed gear. You can see this if you open the printer cover exposing
the inside of the printer. On the solenoid there is a thin piece of foam
which becomes sticky with age and temperature inside the printer. When
the second and subsequent pages are printed, the solenoid the metal flap
sticks to the solenoid and hence the timing of the feeding of paper is
messed up and hence the shifting of printing.
Fix: This is very simple. In the hardware section of your store you will find
thin felt squares or rounds with self-adhesive back normally used on the
bottoms of lamps etc to prevent them from sliding as well as scratching
polished surface of table etc. All you need is one such piece (about
1/2" round) which is stuck on the solenoid side of the solenoid. Thin
felt is preferred. (Cost of a sheet of felt rounds/squares at Walmart is
less than $1.00. All you need is one round).
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
A service manual probably wouldn't be a lot of help. The SX printers (HP LJII,
Apple Laserwriter 2, etc.) are very modular, and AFAIK, the official way to
repair them is to replace the defective module. Of course it's possible to
repair them at a much lower level than that, which is what I do to my pair.
There are 3 motors:
By finding out when the noise occurs, it's possible to figure out what is
causing it.
Firstly the good news. I have never had a main motor bearing fail. They're ball
races anyway (Yes, you can strip the motor down and rebuild it). I've never had
noise from the gear train either.
Now the bad news. Fan failure is common. The bearings are bronze bushes, and
they fail. Sometimes lubrication helps a lot, sometimes things are just too far
gone.
Lower fan. Remove the toner cartridge and paper tray. Turn the printer
upside-down and remove the screws that hold the base cover on. Remove the
cover. The fan is obvious, and is held down by 4 screws (there's a bracket at
one side that comes off as well), and it plugs into the smaller of the PCBs in
the machine. Remove it. You can then unscrew the motor from the fan and slide
the motor + blades out. Then pull the blades off the motor, remove the
circlip, and pull the motor apart. Examine the shafts and bearings. If they're
not too badly worn, a drop of oil (3-in-1 or similar) will probably cure the
fault. Otherwise you need a new fan - parts are impossible to obtain.
Upper fan. Remove the paper tray and toner cartridge. Undo the screws and
remove the outer casing. Remove the 2 screws and lift out the fan duct + ozone
filter (on top of the AC block). The fan is under it and is held down by 3
more screws and a 2-pin plug on the upper (fuser protection) PCB in the AC
block. There are at least 3 different upper fans in use, so I can't give
directions for dismantling them. But in general, the motor can be unscrewed
from the side of the fan, and the bearing on the other side pulled out.
Inspect them as above, and try a drop of oil.
Editor's note: If you buy a replacement for this, it will likely be a 24 VDC
muffin style fan (like in your PC, except that is 12 VDC). HP or Apple will
likely charge you $70 or more for this part!
(From: Frank Reid (reid@indiana.edu).)
If the upper fan fails, the fuser assembly will overheat and do about $200
damage. Cleaning the bronze bushing often solves the problem.
An obscure and obnoxious squeak sometimes comes from the anti-static brush
on the end of the upper fuser roller (end opposite drive gear). A bit of
high-temperature grease on the nearby felt pad will fix it.
I had this problem on my HP LJII. I traced it to D155 shorted on the Fixing
Heater Saftey PCB , this is in the same casing as the AC Power Assembly where
the power cord plugs in. There was some sort of corrosion there.
I replaced it with a IN4148 diode as it is only a signal diode.
We have been replacing these with a SK10466 (800 V, 8 A, Vgt 2 V, Igt 50 mA).
(From: dhickey@knox.edu).
If it is in the AC Powersupply, try a NTE 56006.
Also check for 2 open resistors.
It works fine for a while, then starts to cycle between "12 Printer
Open" and "00 Ready" before the fan in the power supply area drops in
speed at the same time. I notice that the lamp on my desk flickers
occasionally, even when the printer shows "00 Ready". Tapping the
cover at any time immediately brings on the "12 Printer Open" message
and fan speed drop-off. The cycle eventually ends with a "67 Service"
message."
(From: Larry Sabo (lsabo@freenet.carleton.ca).)
The cause of the problem was an intermittent connection in the DC power
supply, where the daughter board is attached to the pcb with a right-angle
connector. I got so tired of removing and reassembling the power supply,
I just jammed an empty plastic scotch tape role to hold it in position, and
it has worked like a charm ever since.
Your problem is likely to be the "Density Control PCB" that if you had the top
cover off the unit, it would be a little board with a lot of wires (mainly
purple, I think) going to it. It is in the front on the top.
About $40. Not saying that's it for sure, but I've seen it three times in the
last 4 months.
(From: Frank Reid (reid@indiana.edu).)
I agree, but it could also be the assembly of photoelectric sensors and
their wiring harness (about $25). Before replacing components, clean the
sensors with compressed air and re-seat their connectors on the DC
Controller board.
(From: Greg Smith (n6nyx@cox.net).)
Check the 10 uF electrolytic capacitor on the Density Control PCA board
to clear Error 12 Open or No EP.
The capacitor on my printer went open-circuit big time! It started off
with an intermittent error message. Percussive maintenance brings it back
for a while, then it dies for good! The capacitor is only rated at about
16 V. I put in a 10 microfarad, 50 volt unit to replace it and still
had plenty of room to clear obstructions after I bent it over a bit!
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
I am not sure how the printer detects that the cover is closed - there
are 2 obvious ways : from the +24 V interlock switch or from the toner
cartridge microswitches. Since, I believe, it'll claim the cover is
closed even without a toner cartridge in place, I think it's the former.
OK, things to check:
Firstly, there should be a little peg on the cover (on the right hand
side under the edge) that goes into a slot on a metal housing on the LV
power supply module. This presses a microswitch inside that housing. This
peg often breaks off.
If that's not it, then take off the bottom cover from the printer and
stand the printer on one side. It's safe to power it up like this. Connect
a voltmeter between the 2 outside pins (1 and 14) on J212 (a long 14 pin
socket on the DC controller board). Power up. If you don't get 24 V here,
you have a LV power supply problem.
Now connect the meter between pins 2 and 13 on the same connector. If you
don't get 24 V now, then the problem is almost certainly the microswitch
in the LV power supply, or the peg that operates it, or something like
that. You can probably fix that by taking out the LV power supply, taking
it apart and examining the switch and its connections.
If you do get 24 V there, then assuming the printer uses the +24 V sensing
as the method of detecting when the cover is one, the problem is possibly
R817, R818 or C760 on the DC controller board. If it's not those, then
it's IC218, a custom microcontroller.
As I said, it _might_ use the toner cartridge switches to detect when the
cover is closed. Take off the upper casing, the frame round the front,
and the LV power supply module. On the side of the power supply there's a
PCB with the paper sensors, the clutch solenoids, and the cartridge
switches on it. Check the latter (SW301 and SW302) and the spring leaf
that operates them.
(From: Erik Welander (erikwelander@hotmail.com).)
I have written a detailed description of how to repair the "Error 12 OPEN or no
EP-L" problem of the Lasejet IIP that seem to be very common on this
printer (cost of approximately $1 for the capacitor). This, and some
general maintenance advice can be found at:
HP Laserjet Maintenance and
Repair.
(From: Terry (tmredding@worldnet.att.net).)
Sometimes the spring tabs on the left side of the printer that are the sensor
for the cartridge get bent or are dirty. Also you get this error if the fan
is not working.
(From: Dave Lee (leedj@uwec.edu).)
Most times I find that its the Density PCA that causes the problem. Sometimes
its just dirt/dust in the two sensors on the right side above the toner
cartridge, blow these out and give it a try. Density Board is avail through
most laser parts houses, these are the ones I use:
(I finally found the cause of the problem described below: One of the voltage
outputs on the main power supply was blown. Had the power supply refurbished
and everything works perfectly.)
I didn't do this. Instead, I took the unit back home and pulled the DC
controller card. I tested all the discrete parts (simple diode tests on
the transistors), and they all test OK. Two questions:
(From: Dave Lee (leedj@uwec.edu).)
Had almost the same problem about a year ago, problem was the AC Power Module,
just needed reseating. ACPM is located in right rear corner, just under ozone
filter and upper cooling fan. Fuser assembly must also be removed to get to
one of the 4 screws that hold the ACPM to frame. Remove the ACPM and then put
back in place, thats all I had to do. Has been working since Feb 1995.
But another thought about this, are you sure that something isn't jammed where
paper from botton tray comes up just in front of the registration assembly.
If you remove the reg. assembly, there is a clear plastic guide that is held
in place by 2 screws. Remove this and check to see if maybe something is
jammed by that sensor.
As far as a good price on DC Controller board, I would call Parts Now, Inc. at
1-800-886-6688 or The Printer Works, 1-800-235-6116. I know that Parts Now
sells either repaired or used or exchanged boards, probably a LOT less than
what you were quoted.
(From: John Meyer (john.meyer@worldnet.att.net).)
Thanks for very complete reply. Your message sparks a lightbulb. When I first
took the cover off when this problems initially surfaced, I took the power
unit apart from the top (took of the little fan, and then started disassembling
it). When I put it back together, things worked. I then put the top main cover
back on, and things didn't work again. Nothing has worked since. However, I
never took the whole assembly out and therefore never got to the connector.
I'll try this and let you know what happens.
I don't use the bottom tray because the bottom paper path is prone to jamming,
and has been for years. However, it is possible that someone (I have a four
year old boy) may have jammed something in there. I have looked for such a jam
and haven't seen it, but based on your input, I will try again.
(From: Dave Lee (leedj@uwec.edu).)
As far as the jamming from bottom tray goes, 2 areas to look at:
Do this after you get the error 13 fixed so you don't compound the problem.
(From: srob@iprolink.co.nz and Michael Schuster (schuster@panix.com).)
Totally different. Different cases, electronics, toner cartridge and system.
(From: Lewis King (echo@infogo.com).)
Error code 52 is 'Scanner Malfunction' and there have been posts on the
USENET newsgroup sci.electronics.repair that indicate that this is fairly
common and is usually the cable leading to the scanner mechanism. These
printers, and the CX before them, use insulation displacement connectors.
Quite often the connection gets flaky and pressing down on the wires where
they enter the connector will fix a problem (worked on my Xante Accel-a-writer
when it was telling me I needed a new DC controller board).
The part you need is the scanner motor... I can't remember the part
number, but it is the same as the scanner motor for a IIP+ and a
IIIP. The scanner motor has three screws holding it in, in the box
where the laser attaches to the side. As you pull off the scanner you
will notice a square microprocessor on it's board. the bottom side of
that board will probably have a dark spot where that processor got too
hot. I fixed about 50 of them that way.
I will find out what the error code means and get back to you.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
That sounds like the classic scanner motor failure on these printers. It's a
very common fault, alas.
The 'Official' repair is to replace the scanner assembly (the entire unit -
the black plastic box - on top of the printer), and if that fails to cure it,
then change the DC controller board. But you can normally fix it a lot cheaper
than that.
Here's how (I believe) the unit should work:
There's a frequency generator (FG) coil on the motor PCB, just like the one in
a VCR. The signal is fed down the cable to J203 on the DC controller and then
converted to a TTL signal by IC202A (LM393 comparator). It enters the gate
array (IC206) and comes out again when it is fed to a TC9142 chip (IC203)
which compares it to a reference clock also from the gate array. The error
output from the PPL is conditioned by IC201b (LM358) and fed back to the
scanner motor. There is feeds the control input of the TA7259 (IC401) chip
which drives the motor windings.
First check that the cables are connected to J203 and J401 (inside the scanner
unit). The most common fault is that IC401 has failed and probably burnt out
R401 (8R2) with it. Fortunately, this chip is not custom - in the UK it's
available from (e.g.) Grandata, so a VCR spares place might have one.
If you've still not got it working, get back to me, and I'll talk you through
the test points on the PLL on the DC controller board. Hopefully the gate array
is still good, since I've not found a source of those.
Oh yes, how to dismantle the scanner to replace the chip.
Firstly remove the outer casing from the printer. Then unplug the 2 cables on
the scanner unit - one on J451 (on the laser PCB) and one on J401 (under the
little flap on top). Undo the clamp screw in the back right corner, swing up
the clamp and remove the beam detect fibre cable. Then remove the 4 screws
and lift out the scanner unit.
Now, *carefully* cut back the melted-over studs and lift off the top
cover. Keep dust to a minimum (obviously). Remove the circlip on the scanner
motor spindle on the bottom of the unit. Remove the rotor and hexagonal
mirror, taking care to note where all the washers go. Remove the small screws
and lift out the PCB.
(From: Flemming (flemming.gottsche@get2net.dk).)
Where the scanner cannot maintain proper speed. Replace electrolytic
capacitors on scanner board. All capacitors are 10 uF/16 V. Also replace
the current measurement shunt resistor (R301) on scanner board. It has a
value of about 1 Ohm. All these parts are in the black plastic box below
processor.
The following Web site has some helpful hints about scanner chip/board
replacement, and also has a scanned datasheet for the chip for those that
want to substitute flatpack/dippack types.
(From: Osceola Electronics (osceola@netonecom.net).)
On my IIP+, I had to take it all apart. I had to remove the main board and
open the main cover to the laser area and clean the fiber-optic pickup and
lens.
A problem on the DC controller (in particular C210) can cause intermittent
ERROR 50's
Mechanical failures of the fuser will not cause ERROR 50 (AFIAK). After all,
the fuser temperature is maintained even when the mechanism is not turning. A
broken gear in the fuser will cause paper jams, but not much more.
If you've got the machine in bits on the bench, and you are *sure* the fuser
is not overheated, try shorting C211 on the DC controller board momentarily
with the power off to clear the error.
(From: Don Hickey (dhickey@knox.knox.edu).)
It could be one out of a number of items that are actually bad. Most likely
it is the fuser assembly. However it could also be the Ac Power Supply, Dc
Controller or the cable going from the fuser to the dcc. Most of the time
the lamp on the fuser burns out or one of the thermal switches.
(From: (Frank Reid (reid@indiana.edu).)
Test for continuity through the large terminals on the fuser. That will
tell you if the lamp and thermostat are good. If they are, then the problem
is in the AC power supply (cubical box under the upper fan). Remove the
printer case, observe the fuser lamp upon power-on. If it lights immediately
and then goes off with an audible click, the triac in the power supply
is shorted. ECG 5620 is a replacement. Be careful desoldering the plated-
through holes.
(From: Charles Kyle (kyle@citynet.net).)
I have repaired a lot of the HP IIP printers with error 52. It has
always been the scanner motor assembly. The assembly can be repaired
by replacing the motor driver IC and possibly a burnt resistor or by
ordering the scanner motor assembly.
Laser Impact carries the scanner motor assembly for the HP IIP. The
part # is RG1-1771-000. it is easy to replace and costs about $60.
Their phone number is (800)879-5882.
(From: Rich (richcar@flash.net).)
The service center gave you the wrong info. It is a bad scanner motor or a
bad dc controller. I have found, that on a lot of laser printers for this
error and others, that if you re-seat all connections internally, to all
PCB's, the problem will go away. (About 50% of the time) If this doesn't work
you can check the voltages on the dc controller itself. The dc controller is
the PCB under the formatter, (If you were looking down on top of the printer)
and directly above the scanner assembly.
These are the voltages the dc controller uses. (From the pwr supply)
The scanner assembly. is the most expensive part and on exchange you can get
one for about $150-200. But don't quote me on that. Contact Printer
Works or PC Service Source to find out. I don't have their numbers but
you should be able to get them from the 800 directory. 800-555-1212
I was finally able to fix the printer by replacing the chip on the scanning
motor board rather than replacing the whole board. That's a $10 fix rather
than a $80 fix!
The surface-mount chip and an associated surface-mount resistor apparently run
hot in this application, and over time, darken the back of the printed circuit
board.
I covered the scanner rotor before attempting anything because I didn't want to
have to clean the mirrors afterwards.
I also have the same chip in a different package that might actually be more
robust. It is the HA13456A, a long DIP package with triple-width ground tabs
in the middle of each side. It is electrically equivalent from what I can tell
and might be a good substitute if the flat pack fails early.
The printer came right up, and self test immediately printed two pages!
The chip came from: B & D Enterprises International, PO Box 460, Main &
Liberty Streets, Russell, Pennsylvania, 16345.
Their worldwide number, as well as tech support (really helpful) is:
814-757-8300 (800-458-6053 in the USA).
Their 24-hour fax number is: 814-757-5400
VISA, MASTERCARD, AMERICAN EXPRESS are accepted worldwide.
Each chip was $7.55. They have a $15 minimum order, so I ordered two, partly
to make the minimum order, and partly to have a spare.
I have repaired many of these power supplies and I usually replace the triac,
two resistors (22 and 150 ohms?) and the eight pin DIP (usually marked SHARP).
(From: Ted Szypulski ( szypulsk@esslink.com).)
Sounds like an open fuser lamp, like mine was. I have an LJ4. HP
would only sell a rebuilt fuser assembly. My cost was $150.00. The
fuser assembly on the 4 comes out the rear real easy. There are two
captive screws to loosen and then it just unplugs. I removed mine and
took it to another LJ4 just to be sure that was the problem before
buying a new one. My testing with an ohm meter also proved the fuser
lamp was open.
I hope the LJ3 is similar and this is of some help.
The common problem with these printers is that the fuser drum gets scratched
by the heat sensors of the fuser assembly which gets dirty with toner. Take
a look at the drum of the fuser if the protective coating was scratched to
the metal. If this is the case then the fuser needs to be replaced (around
$80.00 for refurbished). If the protective coating is not scratched to the
metal then the fuser can be removed and disassembled to clean the heat
sensors. Use alcohol and Q-tips to clean.
To print a test page hit the On_Line button to put it off-line and then press
test button for about 5 seconds.
(From: Frank Reid (reid@indiana.edu).)
Replace the pickup roller. Clean the transfer rollers with naphtha or
mineral spirits. If that doesn't work, replace the transfer assembly
(set of metal and rubber rollers after pickup roller; removable by 4
black screws). Inspect the solenoids on the DC power supply: The
rubber pads sometimes become sticky and hold onto the armatures, thus
messing-up the timing. If that happens, scrape the old pad off, clean
the armature and core with solvent, and replace the pad. I use squares
of double-sided foam tape and then use naphtha to remove the glue from
the outer side. If you remove the old pads but don't replace them, the
printer will be more noisy, and permanent magnetism in the solenoid
cores may affect timing.
(From: Joop van der Velden (joopv@solair1.inter.NL.net).)
Two possibilities: a mechanical problem with the paper transport, or a
escape sequence reprogramming the printer paper format(ting)
Try to print some test pages from the printer itself (no pc connected)
If that gives the same problem, try cleaning the paper path and transport
an paper separation mechanism.
(From: Randy McVittie (rmcvittie@octrf.on.ca).)
I thought it might have been the pick-up roller, at least that is
what the manual was pointing me towards, but other people's 2 cents
worth said to look at the solenoids SL301 and SL302 on the Paper Control
PCA.
There is a piece of foam tape on the core of these solenoids, and it
had become kind of sticky, preventing the solenoid from snapping
back when power was removed. Then I had severe paper jam problems
I guess you need some amount of spacing here. So I put a few layers o
of electrical tape in the same spot and now I had great registration.
3 layers of tape was my magic number, your mileage may vary.
This area was not even mentioned as a source of problem in paper
registration troubleshooting chart in the HP manual.
(From: David J. Pittella (ddc_pitt@ix.netcom.com).)
Since you say the unit 'powers up', I assume you hear the engine power up (fan,
drive motor, etc). Assuming this is a Lajerjet III (not IIIp or IIIsi, etc.),
you can do an engine test by removing a small cover on the bottom of the right
side, removing this cover will expose a metal plate with a hole in it. The hole
exposes a switch on the DC controller which will print simple line test
pattern. This will at least confirm that the engine is working.
The front panel LCD display and status LED's are driven by the formatter board.
The formatter gets its +5 power from the DC controller via (2) screws that
secure the formatter to the CD controller. If you remove the bottom plastics
and bottom pan, the formatter is the large main board. The DC controller is the
smaller board with several connectors attached to it.
I am also making the assumption that the cable leading from the formatter to
the front panel is attached at both ends?
You may also want to remove any options, (memory, optional I/O) as one of these
options could be preventing the formatter from initializing and possibly lead
to a blank display. BUT, the best guess here is that the formatter is not
getting power - check those screws between the DC controller and formatter!
Where the fuser is cold and the relay trips, check Q153 for leakage (C-B)
which results in current leaving the base and charging C158. When C158 is
charged to about 3.3 V, Q153 is turned on and the relay trips.
The relay that is tripping is RL101, which actally is located on another
PWB than the transistor. This relay has a very distinct sound, which has
been mentioned over and over again in postings to various news-groups.
Both PCBs are placed in the rear right corner of the HP LJIII.
(From: Terry (tmredding@worldnet.att.net).)
The most likely cause of this problem is the exit sensor arm or
photointerrupter or the dc controller board. Standing in front of the
printer with the top cover up it will be in the far left lower corner.
(From: Wong Sy Ming (siming@singnet.com.sg).)
Then, the whole thing came apart as I traced the connections for one of the
solenoids back to the DC controller board. Guess what? One of the PCB traces
near the 78324 IC (large square one) was corroded away. I quickly soldered a
wire across it and now it works perfectly! Now I wonder what could have
caused that...?
When I turn on the printer, the light in the fuser comes on for a second.
Then there's a click from the power supply (or around there), and the light
goes off.
The 05 Self Test message comes up.
Then Warming up (takes a while).
Then, both online and page feed lights go out and "50 Service" appears.
The power supply and fan are working and the ozone filter is clear."
(From: Geir Knutsvik (geirk@netpower.no).)
What about the fuser? Does it make heat? I have in some cases have faulty
opto electronics for sensing paper and drawers result in Error 50.
In worst case it cold be the main pcb ...expensive... check dc controller.
(From: Mark Wolfe (markw@wwa.com).)
5 bucks says it's Q101 in the power supply (crosses to NTE 5620). I've seen
quite a few where this was the problem. Check the power connector at the
right end of the fuser, it's under a plastic cover. There should be about
115 VAC there during the warm up, you'll have to stick something in the cover
open switch to get it to power up. If there is 115 VAC, it's the lamp in the
fuser. If there isn't 115, it's save to say it's Q101 which is the triac
that supplies the fuser. Get a new heatsink with the new triac. Cost here
with tax to fix the problem is $7.07 + my labor. :)
(From: Terry (tmredding@worldnet.att.net).)
This error can be caused by missing 24 v, bad Thermistor, Fuser Bulb or
Thermoprotector. Replacing the fusing assembly is quite easy
by removing the 4 silver screws that secure it.
[Error 50, SX Engine]
Remove the fuser (4 screws hidden down holes - it helps to remove the plastic
cover from the left hand side (1 screw).) At the right hand side there's a 2
pin plug that goes into the AC block. Test for continuity between the 2 pins
on the fuser. If it's open, then it's either the fuser lamp or the
overheating-protection thermal switch that's open. It's pretty easy to trace
the connections and test them separately if you can figure out how to
dismantle the fuser (I can talk you through it).
If the fuser is OK, then remove the outer plastic casing, and the AC block
under the upper fan [at the right rear of the printer. Remove the two screws
securing the black plastic ozone filter housing, pull that housing straight up
and off. Three vertical screws secure the base, plus one horizontal one on
the outside rear. Then pull the AC block straight up. The fuser must be
removed prior to removing the AC block].
Most of the time the thing that fails is the Triac, Q101 on the lower board in
the AC block. This means the fuser can't heat up.
Here are a few notes on what goes on in the AC block (totally unofficial,
BTW).
Lower board:
R101, L101, C101, C102, C103 form a mains filter. The output of that goes to
CB1 (circuit breaker) with VZ1 connected across the output of that lot as a
spike suppressor. The output of that goes to the 2-pin plug (J104) and thence
to the DC power supply. Watch out for J104 if you run an AC block out of the
printer as it carries live mains.
The fuser control circuit on the lower board isn't complex either. The live
side of the mains (output of CB1) goes to T101 (current sense transformer)
primary. The other side of the primary goes to the contacts of RL101 (fuser
protection relay). There's a snubber SQ101 across the relay contacts. The
other side of the relay contacts goes to one pin of J103 and thence to the
fuser lamp. The other pin of J103 (and thus the other side of the fuser lamp)
is returned to the neutral side of the mains via the triac Q101. This is
triggered by SSR101. Oh, there are a couple of resistors (R102 and R103) in
the triac gate circuit, and suppression components L102 and SQ102.
There's a 10 pin connector between the lower board and the upper board. The
pinout seems to be:
The last 4 pins are connected to the 4 pins of J101 which is connected to the
DC controller. Shouldn't be hard to trace those.
Upper board:
This virtually never fails, so I'll simplify the description by missing out
resistors, etc. You can trace the signal flow from this description anyway.
The fan control is trivial - the fan control input drives Q159 with the fan as
the collector load.
The fuser control signal is AC coupled (C157) to Q157. The output of that is
rectified/smoothed (D157/C156) and drives Q156. The collector load of Q156 is
SSR101 on the lower board.
There's also a protection circuit, which works as follows. Normally Q153 is on
which turns on Q152 and Q151. This turns off Q155 which has the protection
relay as its collector load.
If the fuser control circuit fails so that Q156 stays on too long (which would
cause the fuser to overheat), then C153 is discharged by D155 and the
collector of Q156. This turns off Q153, Q152, Q151 and turns on Q155,
energizing the protection relay and turning off the fuser.
If the fuser takes too much current then the output of the sense transformer
T101 becomes large enough to trip the comparator IC151 (LM393). This turns on
Q154 which discharges C153. The rest of the circuit operates as above.
(From: Jon Martin (jon.martin@unisys.com).)
There is a partial Schematic of the AC power supply at:
Fuser Controller RG1-1438.
The fuser thermistor comes in on pin 4 or J206. There's an 18k resistor
(R237) to +5 V, and a 4.3K resistor to ground via SW205 (which is open when
the base cover is on the printer -- the idea is to shut the fuser down if
you power up the printer when dismantled). Then there's a 3.3K resistor in
series (R747). And then a 4.7 uF cap (C210) to ground to smooth the signal
out a bit. Finally we get the AN0 input on the main microcontroller IC218.
The fuser drive signal comes out on port PD2. This is buffered by IC219e
('04) and IC211e ('07) before going to pin 2 of J208 and then to the AC block.
There is one more bit of circuitry to consider -- the overheat shutdown.
If the fuser overheats (or the machine things it has), then a signal
comes out on port PD3. This turns on Q210 (2SC1815) which charges C211
(100 uF) via R749 (330 ohms). There's a 4.7M resistor (R748) in parallel with
C211, which gives a time constant of many minutes. That's why to have
to leave the printer off if the fuser seems to have overheated. Anyway,
the voltage across C211 is monitored by the AN3 input on the
microcontroller
So, what to check? C210 is a favorite, it goes leaky. If that's not it,
check (with the printer assembled and therefore SW205 open -- you have to
solder wires onto the points so you can look at the signals) the following
If the microcontroller is faulty then as far as I know, the only place to get
a replacement is off another DC controller board.
(From: Frank Reid (reid@indiana.edu).)
If the paper is getting crunched accordion-style, the 'drum-drive clutch'
is probably broken. It's a couple of small white gears inside the
right-side cover of the machine. The plastic tends to crack in a ring,
separating the gear from the shaft. To confirm, mark the green drum in
the toner cartridge: If it doesn't turn, then the clutch is surely at
fault. Apple "Personal Laser Writer" and some other brands use the same
print-engine.
If the machine won't pick up paper at all but the pickup rollers are good,
look for a bent piece of metal preventing movement of the bar that raises
the stack of paper just prior to pickup.
A third possibility is stripped plastic gears on the fuser assembly.
(From: Lars Arvidsson (arvid@plea.se).)
My guess is the paper intake rubber reel, you see it if you pull out
the paper tray. It gets old and dry, and it needs to be sticky
to get a grip on the sheet. It gets worse at dry weather, cold and dry.
Try to clean it with alcohol, then coat it with some balsam turpentine
(don't know if this is the right translation, it's a liquid used for
diluting artist oil paint).
Allow it to be absorbed for a few hours, then wipe of the excess.
The reel is sticky again...or just replace it - but that's no fun. ;-)
(From: Rick Norton (RKNORTON@worldnet.att.net).)
I repaired an HPII with a similar problem using automotive belt dressing on
the rubber pickup surfaces. Spray a small amount on a rag and wipe on
surface. Allow to dry for 15 minutes. The printer has been working for 3
years without a problem.
(From: Dr. John Betts (Dr@browser.demon.co.uk).)
Don't ignore a more mundane cause - that paper is stuck inside the fuser,
particularly if someone has used inferior grade labels.
(From: Pete (PTCull@lbl.gov).)
If you have a voltmeter, J212 on the DC Controller is a good place to start
checking. Blue wires are earth/ground, brown is +5 VDC, orange is +12VDC, and
the red wires have +24VDC.
However, it sounds like a nice time for known good spares or another known
good LX engine to borrow known good assemblies from.
The machine goes through its warm up routine OK but if I do an internal
font printout or print from a PC then it sits quitely for about ten seconds,
then raises in pitch for a second and simultaneously displays: 52 ERROR.
The manual states that this error is a 'scanner fault'.
I have dismantled the unit down to the laser and rotating mirror but can see
no obvious faults. Perhaps the motor that drives the mirror is burnt out or
the laser is dead??
HP have quoted me a repair price equivalent to a new Oki!!!
(From: Frank Reid (reid@indiana.edu).)
That symptom can often be cured by re-seating the cables between the laser
assembly and the dc controller (smaller board under bottom cover). Also
check the optical fiber running from the laser scanner housing to the dc
controller: Sometimes it goes bad or the end gets dirty. If you can shine
a flashlight through it, it's probably ok.
(From: Ralph Wade Phillips (ralphp@prysm.net).)
About 50% dead laser and 50% bad DC controllers (photoreceptor
dies, or interface chip it drives is dead ... gives SAME error!)
Without a spare printer for parts, it'll cost you about a new
printer for parts ... sigh.
(From: John Fiskio-Lasseter (johnl@yin.earlham.edu).)
Not necessarily. There are a number of places where you can simply buy
the parts themselves, often refurbed - even a DC controller and laser
assembly together would be cheaper than getting another printer.
Adam, at a guess, I'd say that you really are looking at a failed
laser/scanner assembly. Of the possible causes, that's the part that gets
the most wear and tear, and the most likely to fail under normal operating
conditions.
A few places to try for parts:
Both PW and LI will do repair, parts sales, and exchange parts sales, and
you may find them a good bit cheaper than Hewlett-Packard.
Also note that the engine parts from all other HP LaserJet II's and III's
are interchangeable with yours. So are the engine parts (except the DC
controller) from the Apple LaserWriter II printers. Other printers based
on the same Canon SX engine are: QMS 410, Brother HL-8e, and several
others that I can't remember off the top of my head.
(From: Steve Pepin (steve.pepin@mogur.com).)
You may not need to dump the printer or even pay for a new scanner assembly.
I had exactly the same problem with mine and it turned out to be only the
cable that attaches the scanner assembly to the main PCB. It's only a $28
part and you can possibly simply repair the one you have. I don't know how
mine failed, but that is what our local HP service center replaced.
(From: Frank Reid (reid@indiana.edu).)
Correct! I repair at least 100 of those things per year. The connections
fail far more often than the $canner. The problem can usually be solved
by removing and re-seating the connectors on both ends of the cables that
connect the scanner and laser to the 'dc controller' board (smaller board
under bottom cover).
(From: TAltmeyer (taltmeyer@aol.com).)
Sometimes the driver-IC for the mirror motor is defect. It's a circuit from
Hitachi HA1XXXX, i can't remember the number exactly. A half year ago
i had such a printer with error 52 and i replaced the chip and all was fine.
The chip is a little bit difficult to get but if your're encouraged enough
you can get it (after a lot of telephone talking) from your local hitachi
distributor. It's much cheaper than a complete unit :).). The scannerunit
itself was made by Canon (as the complete printerdrive is made by Canon)
(From: Jim Hunt (jhuntjr@b-c-i.com).)
I believe this is the message you get after printing 200,000 (I might be
wrong) copies which is a reminder to replace the fuser unit. This comes in
a kit with new pickup rollers and several other pieces. It is pretty easy
to replace
I have seen this problem quite a few times and I check the fuser lamp to
find it was manufactured by USHIO. After replacement with a Toshiba lamp
(not an endorsement, just what the supplier sends) the problem is gone. I
haven't ever had this problem and not found that brand of heat lamp in the
fuser......
I'm a field engineer and deal with quite a lot of printers. What is quite a
common cause for this problem is damp paper or using the printer in a damp
room. Try a brand new ream (direct from store) and try using in a warm room
and see if the problem goes away. I've been having this problem a lot
lately as the weather has turned a bit - most of my customers store the
paper in store rooms and it gets a bit damp. Incidentally HP printers in
particular seem to be suffering from this quite a bit.
Here are the empirically determined SIMM codes for the HP LJ5:
(o for open circuit, g for grounded jumper)
Since there are several codes that have the same RAM size, it's possible
that they correspond to different RAM speeds or other differences that
might matter. I connected my $129 16MB 70ns 32-bit-wide 72 pin SIMM in
the g o o g pattern, and so far it seems to work OK.
If anyone has more info, such as speed or other characteristics that
ought to match the ambiguous codes, I'd be very interested.
Some of these codes correspond to the RAM/ROM PostScript SIMM, but
those seem to be driven from a logic array and might have more
complex behavior. In particular, no static code was interpreted as
such a PS SIMM, but that might be because it already found one
in another slot.
With a duplexer, the LJ5M barely functioned with the original 6MB RAM,
had to run it at 300 dpi or it would just not bother to duplex.
Borrowing 4M from my old LJ4M raised it to 10M, which raised the
performance ENORMOUSLY. 16M raises it to 22M, which is surely major
overkill, but for $129+tax at Fry's, why go for less.
So far the software on my Mac is refusing to control the duplexing
features, e.g. the "which edge is the binding edge" choices are
always disabled, but turning it on at the printer works (unselectively).
But maybe this is due to some beta printing environment stuff I'm using.
(From: Leif Gastgivar (lgastgiv@technis.syh.fi).)
I bought a new HP Laserjet 5L printer and I just plugged the printer into
the socket. After a time the printer started to print out pages by its
own. I checked out the manual but I couldn't find out the problem. But
after a wile I find out, that the printer wasn't connected to the
ground. After I fixed the problem, it will have been working properly.
If the boundary is sharp and constant, logic is likely but not always.
If the boundary is fuzzy and/or ragged, blockage in the optical path is more
likely - a label or Post-It(tm) note that escaped, or even a wad of dust or
other debris.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
Does the printer have an 'Engine Test' switch (a button on the DC controller
PCB on the LaserJet 2, and one on the side of the LaserJet 1)?
This will cause it to print a test page (of vertical lines normally) even
if the formatter board (the thing that translates the incoming data into
a bit stream to send to the laser) is defective.
If you can find such a button (it's hidden on the side of the lower cover
on the Laserjet 2), press it and see what happens. If you only get half
a page, then the fault is almost certainly optical (Check for defective
mirrors, etc as mentioned earlier in this thread). If you get an entire
page of lines, then the fault is in the formatter board. I have no info
at all on any formatters other than the Apple Laserwriter 2NT one, alas
(From: Ralph Wade Phillips (ralphp@gcstation.net).)
On one side of the bottom, there's a cover that can be removed
after removing one screw. After that, the button is visible through a hole.
Only push this AFTER it warms up all the way - it's ignored until the engine
is ready!
(From: Al Savage (asavage@iname.com).)
Piece of cake. Replace the pickup rollers. You can clean them, but it won't
last.
Now, the bad news: it's not real easy. Or, like most things, it's really easy
once you've done it a couple of dozen times.
The rollers themselves are about $5 these days, and have been redesigned to
eliminate one problem they used to have: you can't put them on backwards
anymore!
LaserJet IIID: remove all exterior plastic: three screws up top accessed after
opening the lid. One screw horizontally near AC power cord receptacle.
Release nasty catch of top lid from side plastic at just above AC receptacle.
Try hard not to break top lid while doing this. :)
Now you can access two screws retaining front edge of side panels to front
panel. Remove two vertical screws holding left side panel to rear of printer
chassis, near fuser.
Unhook front panel operator panel cable, remove front panel assy.
Remove six small screws retaining front chassis subframe to (scanner, HVPS, DC
PS), plus about five larger screws holding power envelope feeder subframe to
front.
Remove DCPS on right front of chassis: remove three vertical large screws (two
in front, one at right rear). Disconnect main motor harness from DCPS.
Disconnect gray fibre optic cable from black clip at left front edge of DCPS,
or it will be damaged, and you'll add another large batch of screws to
remove/replace! Then remove DCPS by grasping firmly and pulling straight up.
This takes considerable force, as there are connectors at the bottom that you
are separating.
I recommend removing the registration assy prior to removing the paper pickup
assy, but it can be done without. To remove the registration assembly, remove
four vertical screws (three black, one chrome, most likely on III series) from
reg assy, which is the part with the green "handle" just inside the paper
path, as you look straight down into the printer. The left rear (shiny) screw
will likely have a short ground wire under it on a III. With the DCPS out,
the reg assy will just lift straight out. Note carefully the bronze ground
lug at the left front of the reg. assy. It must be rotated forward at
reassembly or the forward black roller (small diameter, 9" long) on the reg
assy won't be grounded, and you'll get all kinds of odd print quality
problems. Look at it now, BEFORE removing the reg assy, to see how it's
supposed to look.
Using long #2 Phillips, remove two small screws retaining the pickup assy (the
shaft with the grey PU roller on it, plus the black or white spring clutch on
the right end of the shaft) black plastic bearing blocks. Lift up PU assy,
slide 2" to right (the reason you had to remove the DCPS), then swing left end
rearward to where the reg assy used to be, and remove.
To replace the PU roll: remove E clip on left end of shaft, slide off all the
washers, spacers, etc, noting the order carefully. Roll just falls off!
On reassembly, don't forget to reconnect the main motor's wire harness to the
DSPS. One of my common problems.
If you're going to do the lower PU roll, do it now, prior to reassembling the
top half. Remove the lower side plastic panels -- one horizontal screw in
back for each side.
After removing the sides, remove the E clip on the left side of the lower
pickup assy, then remove the bronze shaft bushing. Don't lose it.
On the right side, remove the three small horizontal screws on the clutch
plate, disconnect the clutch's harness from the chassis harness and harness
hold-down clip, then rotate the clutch plate and slide the lower PU assy out
the right side.
Replacing the PU roll is identical to doing the top one at this point.
Now you know why I charge 1.5 hours to do top & bottom rolls. Plus, I pull
the lower pan and vacuum it out, Fedron the reg assy, and replace upper/lower
fans if needed.
The IIID is the best laser printer HP ever made, barring the Si series. Well
worth the effort and expense, even if you have to replace the fuser too. I
like them a lot.
Done right, a proper PM of a IID or IIID involves removing the upper unit from
the lower to properly clean the skewed feed roller, but that's another 30
minutes, plus cleaning the refeed assy. You can "kinda" clean that lower feed
roller (not the PU roller) if you have small hands and a long Q-tip, but it
really isn't a good job.
PS: oh, yeah. I wrote this all from memory, and I haven't done one in
a couple of weeks, so I just *might* have overlooked something. But
the major steps are there. Keep track of the various screws, they're
not all interchangeable.
(From: Frank Reid (reid@indiana.edu).)
The fuser lamp often fails in that model. The replacement is Apple
part number 890-0427. I think it costs roughly $25.
(From: Erik Johansson (erijo105@student.liu.se).)
The ports are a Phonenet Appletalk connector, a 50 pin centronics-like
scsi connector (to connect a font cache hard disk), 25 pin female D-sub
serial connector (wired as a DTE so the cable should be the same as when
connecting to computers, not a computer and a modem) and a RS-422 8 pin
miniDIN connector (also for serial communication).
The jumper settings:
I suggest that you cruise on over to
The Printer Works and check out the
blowup parts list for the LaserWriter and LaserWriter Plus mechanical (Canon
CX engine - also LaserJet, LaserJet 500, LaserJet Plus, and several, SEVERAL
other printers). That will make the text easier to follow. (Use the search
facility for the printer model - that will include the "Parts Identification
Diagrams".)
To repair the MOST common problem with consistent jams at the paper INLET, you
have to strip the printer down to where you can remove the Registration
Shutter Assembly. Due to how the LaserWriter I/O board is connected, you'll
have to remove the I/O board (the big one with the Plus ROMS on it), and the
case it's in (Note: DISCONNECT the board from the computer's wiring harness,
do NOT try to remove it from the case. The case should come off also - leave
it mounted there.) After that, you can see the registration shutter mounting
screws, along with the wiring harness for the shutter solenoid AND for the
cartridge installed/sensitivity microswitches. Remove the shutter assembly.
You'll have to either dismantle it and clean the solenoid out, quite possibly
having to replace the rubber bumpers, or you'll have to replace it.
I have left out the most obvious steps of removing the upper housing and
several other steps - they should be obvious from the parts diagrams for the
printer.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
(The wiper blade which is inside the toner cartridge on these printers may
be warped/defective --- sam).
On a Laserwriter 2 series (the most common one IMHO):
With the top cover open, look for 2 ping contacts in a little white pillar
attached to the cover on the left-hand side. When the cover it closed, it makes
contact with 2 similar contacts on the PCB on the left side of the fuser.
Check for continuity (but not 0 resistance) between the 2 contacts _on the
cover_. If it tests O/C, remove the toner cartridge (you did that, right?),
then the little metal plate (grey metal, held on by 1 screw) behind it, then
undo the 2 terminal screws under this, undo 2 more screws on the large
grey metal assembly, and remove it. Inside this are 5 bulbs in series, one
of which has probably blown. You can get replacements from the PrinterWorks
If those bulbs are OK, then check the power transistor on the PCB on the left
end of the fuser.
A good possibility is the cable from the scanner to the DC controller. It
might just need to be re-seated. Might need replacing.
(From: Ralph Wade Phillips (ralphp@gcstation.net).)
It means that the fuser isn't getting to proper heat. This might
be a blown fuser, might be a bad AC Input Block, might be a bad DC
controller.
Before I fought TOO hard, I would pull the fuser assembly and check the
115 VAC inputs for continuity. If you don't have any, then I'd say you
most likely have an open fuser lamp, and it will need to be replaced.
If you have continuity, I'd change out the AC Input Block, and
work from there.
The DC controller being dead is rare, but it *can* cause the same symptoms.
(From: Mark Wolfe (markw@wwa.com).)
Do what the other guy said, but instead of replacing the AC Power
Block, check the triac at Q101 inside the ac power block. Common
failure on this engine. When you do fix it, put a good heat sink on
the thing.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
The click is almost certainly the fuser protection relay dropping out. This
relay is located in the AC input block assembly at one end of the fuser, under
the main cooling fan.
This relay is on the lower board in that module, and is driven by the
protection circuit (a few transistors, not hard to trace out if needed) on the
upper board. It operates if the fuser drive signal from the DC controller is
active for too long at a time - it prevents the fuser from overheating if one
of the CPUs on the DC controller goes crazy
OK, things to check:
There aren't many (if any) electronics faults that can cause this,
thankfully...
First press the test button on the side of the bottom casing round the
back. Does the test printout also have this strip missing? If not, then
you've got a very strange problem with the formatter board, and I'll have
to think again...
Secondly, take out the cartridge and shake it, and put it back in. If that
doesn't help, then try a new toner cartridge.
If you've still got problems, then the most likely problem is something
in the beam. SX engines (which you have, and CX engines and...) print
black where the drum is discharged by the laser [1]. Start by removing
the toner cartridge. There's a black metal strip in the top cover above
the toner cartridge. By fiddling with it you can move it slightly,
exposing a front-silvered mirror. Inspect that for bits of paper, etc.
Clean it _very_ carefully.
Next area to look at is the laser scanner itself. If you know what you
are doing, take off the outer casing (screws round the outside, some
under the lip that the lid closes onto, and 2 on a metal bracket at the
left side of the fuser) and look at the scanner block. This is the black
thing mounted over the paper tray. Unplug the cables (one to the laser PCB
itself, one to the scanner motor under the little flap on top), undo the
small screw to release the optical fiber, and undo the 4 screws that hold
the scanner in place. Lift it out. Look at the slot on the front edge for
any paper, etc. I don't know if I recommend you opening the scanner
(Canon DO NOT, but I've done it), but you can carefully trim back the
heat-moulded studs and open the cover. Look for debris inside. Handle it
with great care, of course.
(From: Ken Eckert (eckert@sfu.ca).)
One problem that gives this printout is loose screws on a plate in the top
cover above the toner cartridge. The screw(s) fall out and get stuck in the
toner shutter window that that the laser goes through. I've had a couple like
that, I made it a habit to tighten those screws whenever I work on one of
these Canon engines.
(From: Ralph Wade Phillips" (ralphp@techie.com).)
There are two ways. One is to swap the eight or sixteen ROMS from the Plus
into the same sockets on the LaserWriter, !AND! to swap the programming shunt
assembly ( a set of four jumpers in a 16 or 24 pin DIP socket), placing it in
the exact SAME place. The easier way, if you have both printers, would be to
remove the upper cage and swap THAT. This will mess up the page count,
however, that's not such a big deal nowadays (not on a CX engine - after all,
does it REALLY matter on a '88 Dodge Aries K that it's got 213K miles or 127K
miles? ... )
Both my 300 dpi Brother 641 (sold as the 630 in the USA), and my friend's
600 dpi version of the same printer, had a problem where toner ended up
all over the page. What a mess.
The problem was that there is a long thin spring that is rotated at one
end, and propels the used toner (scraped off the drum) back to the point
where toner enters from the toner container. It acts like an Archemedes'
Screw, gradually transporting used toner back again for reuse. It also
transports fibers of paper that have been scraped off, and therein lies
the problem. Brother stupidly "closed" the end of the long spring (its
last coil is bent to be in contact with the coil before). The result is
that paper fibers (once they reach the end of the spring), get caught in
the closed end of the spring and cannot get out.
The fibers build up until they jam the end of the spring and it can no
longer rotate. The drive mechanism doesn't know this, and keeps rotating
the spring until it breaks (usually right at the driven end).
The solution is to disassemble the printer drum (not all that hard, but
not for the faint of heart!), remove the spring (it's about 15 inches
long), and bend the end so it engages into the drive gear again. Then,
eliminate the original problem by opening the last coil at the far end,
so fibers can get out.
(From Owen Solberg (osolberg@infinex.com).)
If your Sharp JX-9460 laser printer has decided it is time to give you
the "REPL.DRUM" message on the LCD screen, but the print quality is
still fine, then all you need to do is fool the page counter to think a
new drum has been put in. Here's how:
Anyway, the theory behind this is that the new cartridge comes with a fuse in
it which is blown by the 4 volts the first time you insert the cartridge.
That is what resets the counter. Better than spending $190 on a new drum,
right?
This laser printer uses the Sharp JX9500 engine and I was able to find
out how to get it into diagnostics mode. I selected "Test Print" and
it returned "Service (C2) 01". The stepper motor appeared to be working
correctly along with the fuser lamp."
(From: All Laser Service (laser@ix.netcom.com).)
The lubricant used on the gear train tends to gum up and the motor
strains to the point that you receive a main motor error. Take the
complete gear train apart and clean it. You will need to disassemble
all the gears and clean both the gears and the axles. Also take a look
at the developer and drum cartridges as they are driven by this gear
train. If they are jammed this will also cause your problem.
(From: Robert Blackshaw (blckshaw@clark.net).)
Try The Printer Works at http://www.printerworks.com.
I fixed an HP Laserwriter II (same engine as the NT) with exactly the same
problem, a $0.49 gear on the fuser assembly. On top of it all their catalogs
are like service manuals with exploded diagrams of everything.
Both have defects in the Toner Fixing unit (Fuser roller?). Which is
the unit that melts the toner onto the paper.
One unit has VERY BAD scratches on the Toner fix roller itself, which
causes a bad streak on pages.
On the other unit the heating element on the Toner fixer has blown.
The big question is can I take the heater from one, and place it in
the roller of the other? Anyone done this? A new roller unit will cost
me 90 quid, so a couple of hours to actually do it is worthwhile, as a
working laser printer will be the result."
(From: JStev55598 (jstev55598@aol.com).)
No problem if you are careful when swapping over the fuser lamp you will
have a working printer which is a darn site cheaper than a re-con unit.
One thing to bare in mind is what made the lamp fail in the first place.
Although it has usually got to the end of it's natural life sometimes a
failure in the temperature sensor or a power supply fault can cause the
lamp to overheat.
When turning it on for the first time after replacing the lamp check that it
switches on and off after it's initial warm up . You can sometimes see the
lamp when it is on through a vent in the side of the printer by the end of
the fuser roller.
The drum sensor on my 5400 is an opto-interrupter that sits over an
opaque flag that's connected to a bucket inside the waste-toner
compartment on the drum. When the bucket is full, the flag blocks the
sensor and causes the CHNG DRUM indication.
Carefully drill a hole to get the toner out and BE CAREFUL OF THE DRUM
SURFACE. I killed mine doing this. What sucks is that when this
happened I was getting the indication and I only had 4400 pages on it
(it's a 6000 page life span, supposedly).
when you're done, power up the printer while depressing ENTER. The
display should tell you "DRUM COUNTER RESET" or something like that.
Another fun thing I really love about the printer is how the developer
mechanism--the magnetic drum that picks up toner--is permanently
mounted in the printer. Lots of fun if the scraper is removing toner
in one spot and you can't clean it. :( (A slip of paper *somewhat*
works.) I only found this out after tearing my printer down
*completely* and removing every last bit of old toner.
After 3 years, I'm *not* happy with my printer any longer. Though
it's had a new drum, it has *never* worked the same since it was
changed out. White streaks on the output where there's not enough
toner. And smeared characters where there's *too* much toner. *sigh*
It goes against our dogma here to say this, but I am very tempted to
throw my printer out the window. (And I say this as a Panasonic owner
who loves his 27-inch TV.) It's not repairable, I'm tired of tearing
down the printer for a fault I can't possibly fix. And I'm tired of
blowing another $70 on a drum that will die before I know it. Not
when I can get a new printer for about the same price, 600 DPI and at
least 12,000 pages before I have to spend big bucks on a drum. Like
Curly Sue, when it was good it was very very good but when it's
bad....
E31 is the most common reason for a 4420 to fail.
The manual says that 'fusing unit failed to reach x degrees in 90 seconds' or
words to that effect. Makes you think of fuser problems, right? Bulb,
thermal fuse, thermistor? Well, only about 1 out of 10 times.
The problem is solder blown off two pins in the AC power supply, located on
the front left side of the printer (after removing plastic cover) as you face
the front. Easy fix, if you're moderately handy.
E31 and dirty feed rollers (and paper pickup roller) are about the only things
that fail on a 4420. Well, you do need to replace the developer and drum
every so often, and they're pretty expensive, but they're long-lived, too.
Much lower cost-per-page than any HP product.
I happen to think the 4420 was Panasonic's best-made laser printer. The 4450
is over twice as fast, at 11 pages/minute, but you can't really run laser
label through it. And it's MUCH harder to service.
I issued the incantation to reset this message. It now works again,
but the display is flashing 'Change DEV' and 'Change Drum'. This
makes it more difficult to use the menu system. I'd like to turn them off.
From the dealer's explanation, I gather that there are fuses in both
the developer and the drum. When you install a new one, the machine
senses the fuse, resets the counter then blows the fuse. If this is
true, I should be able to bridge the fuses with another and reset the
counters. Maybe even a resistor will do it. Or maybe even a reset
switch somewhere?
Can anyone tell me how to reset the error messages for the developer
and the drum? I'm willing to disassemble the thing to do this."
(From: Jeff Roberts ( jroberts@axionet.com).)
(From: Mark Wilson (mawilson@worldnet.att.net).)
There must be something additional to that. I tried it on my 4420 and
it did not work. Can anyone shed additional light on this??
(From: Jeff Wilkinson (laser@ix.netcom.com).)
The fuse on the drum unit burns out when you first install it. This
momentarily shorts the input to a counter IC and resets the counter. I
would be very careful about shorting it with a piece of wire, even
though the circuit is current limited it is just not a safe practice.
Of course you could always replace the drum! The same is true for the
developer unit. The developer and drum unit should have been replaced
at both 18K and 36K pages as they have reached there useful life
expectancy. E-mail me if you want more info, I believe I have the value
of the fuse required here someplace.
(From: Mark Wilson (mawilson@worldnet.att.net).)
I believe there is a module with a microfuse, similar to the one on
the toner cartridge. If this is so, you have to replace the
microfuse (preferred) or short it with a piece of wire (not
recommended). The fuse burns out after so many pages,
triggering the drum message. When the drum is replaced,
it has a new (intact) fuse.
(From: Robert Blackshaw (blckshaw@clark.net).)
Lotsa luck! I have an HP LaserJet 500+, an Apple Lasewriter Plus, and a Xante
AcceleWriter which were DOA and which all now see active duty. The only
piece of information that I have that is very useful is the HP Printer Service
Manual P/N 02686-90920 that I got *after* solving the LaserWriter Plus'
problems.
I went through Border's Books and other computer book shops looking for
anything covering laser printer internals with no luck at all. It's your brain
and logic, and luck.
One thing that will cause you grief on the older CX engine based printers
are those *insulation displacement* connectors they used. Occasional no
contact problems are usually solved by pressing the wires into the plug.
It looks just like a standard fuse, as found in power supplies. The
usually-glass part is made of white plastic. There is a window on one
side, made of a clear material(glass, plastic?) And there is a scale
next to the window, 0 to 10.
In the window is some substance that looks like mercury from end to
end, but there is a "break" somewhere in the middle (around 3 or 4
on the scale)."
(From: Tony Duell (ard@p850ug1.demon.co.uk).).
The substance is mercury, AFAIK, and in the 'gap' there's a small amount
of some electrolyte. Passing current (very low current) through the device
electroplates mercury from one column to the other, thus making the gap
appear to move along the tube.
It can be used in 2 ways - if a constant current is passed through it, it
records the total time that the unit has been in use. That is the more
normal way to use it.
However, in the CX, it's fed with a short pulse of current at the start
of each page. Thus, a small amount of mercury is transferred for each
page printed, and the device does, indeed, operate as a page counter.
(From: Frank Reid (reid@indiana.edu).)
If changing the toner cartridge doesn't fix it, the lower (rubber) fuser
roller may be bad. Those (at least in HP printers) sometimes don't pinch
the paper tightly enough during fusing, causing smears.
The fuser has a teflon-coated hollow metal roller with a heat lamp inside,
and another roller which pinches the paper against the hot roller during
fusing. The lower roller is made of high-temperature silicone rubber.
Those sometimes go bad as described above, but if you have replaced the
whole fuser assembly recently, it probably isn't the problem.
Look for any rollers between the pickup roller and the fuser, and clean them
with naphtha or mineral spirits. If there is a black roller with foam-like
surface, that one is electrically conductive and is part of the mechanism
that places electrical charge on the paper. Clean it with alcohol and do
not get fingerprints on it. Clean everything in the paper path: If there is
a corona wire (instead of the conductive roller), clean it with a Q-tip
dipped in alcohol.
Bad rubber is a very likely possibility. There are rubber restorer
chemicals - don't know how well they would work. Sanding the top
layer may help. Replacement would be best if you can locate parts.
(From: FAXFIXR (justdfax@cdepot.net).)
I would bet the "picker fingers" or "separation claws" are in need of
replacing. They are the claw type pieces that ride on the roller and
prevent paper from sticking to the roller. The end that rides on the roller
will build up a coating of toner and crud and will wear a groove thru the
teflon coating of the roller. Once the teflon coating is gone, toner builds
up in the groove and shows up on each page as a faint line.
(From: Gerald Chafee (GChafee@worldnet.att.net>).)
If I remember right the original Laserjet has a "test switch" located
towards the back that only tests the print engine and is supposed to
only print parallel lines. I think that you can take the printer
off-line from the front panel and get some sort of printout by holding
down a self-test switch on the front or a combination of switches.
Somewhere I have a service manual for this unit and I will try to look
it up.
BTW, the LJ I's were invariably a serial port only printer which made
them a pain to interface. They do give a good print for such old
technology, but you only have 1 or 2 resident fonts and I believe there
was no graphics capability. You had to use cartridges to get any other
fonts.
(From: Mike B. (osiris@avana.net).)
It's printing correctly. If I remember, there are two ways of testing
this thing. You are hitting the 'test print' button on the side. This
is the parallel lines test. There is another test button on the front
panel that when hit, causes the cascading alphanumeric printing sequence.
With Win95, you should be able to use the HP Laserjet driver with no problems.
Since you have Model #2686A, I think the 'A' stands for parallel connection.
In that case, just connect it like any other parallel printer, and make sure
that you have the proper Win95 drivers.
Why doesn't the HP site help much? :-). They just want to sell you one of
their new, whiz-bang models :0
This printer is a great workhorse. I believe you will still find lots of
support for it from other places. There is a place called Laser Connection
that supports/services these printers.
These printers need a new drum every 4-5 toner refills. They are designed that
way to fool you into buying them as the toner is cheap. Then they get you
later at drum time. The drum is a consumable and does NOT last the life of
the printer. Resign yourself to a new drum every 4-5 toners or so. That's the
system.
(From: Chris Laudan (chris.laudan@zetnet.co.uk).)
Yup, agree with this. The cleaner unit has a fine clear plastic strip that
removes old toner from a roller, in time this develops fine kinks or scratches
which let old toner stay on roller, hence streaks. If this strip is OK and
machine says need new cleaner unit, you *can* carefully empty cleaner unit and
carry on, but you must be careful not to damage strip doing this. Best to
replace unit as above,
Please does anyone know if the fuser roller is an integral part of the
OKI OL400/800 Image Drum Cartridge replacement kit? If not, any ideas
on the part number, please?"
(From: Al Savage (asavage@iname.com).)
Note that an OL400 is nothing like an OL400e. Almost no parts interchange
including the drum/developer assemblies.
(From: Brian Hughes (bkhughes@gisco.net).)
The problem you're both describing is caused by the "wiper blade" in
the drum cartridge, not the fuser! OKI doesn't sell the part and says
when you have this problem you must replace the entire image drum
assembly $$$$
The cure is really quite simple: I remove the entire drum cartridge
and place it on newspaper under subdued lighting (you don't want to
"shock" the drum). The corona wire assembly can be recognized by the
sliding blue knob on top; I release the left side with a small
screwdriver tip and remove it. After removing the two screws I have
just uncovered, I lift the blade free. Gently wiping the accumulated
toner off the blade allows me to see the rubber better. If I see that
the blade has "curl", I can then weight it down on my bench for a
while to reverse the curl before I reassemble it. Sometimes all it
takes is the cleaning. I have done this with my own "preowned" OL400,
and now enjoy like-new printing.
The one that stumps me is where to find a fuser lamp, OKI will only
sell the fuser assembly (major part!).
DISCLAIMER: Due to the possible health hazards of toner dust, I have only told
you what I have done...it is your choice, and your responsibility to take
precautions should you disassemble your printer.
(From: George Hurley (ghurley@voicenet.com).)
That smudge on the first page is your OL400 telling you that
your image drum is getting old - they're about $240 from Staples, or $180
rebuilt. HOWEVER, the actual cause of the smudge is the failure of the
toner wiper blade inside the image drum assembly. This acts like a
windshield wiper and scrapes excess toner off the drum. When it hardens
with age, it stops working as well as it should. This blade can be
replaced at fairly low cost - I bought one for $25 and suspect that I
overpaid, and it took about ten minutes to replace the old one. You'll
eventually need a new drum assembly, but this repair should squeeze
another 10-15,000 pages out of the drum.
I forget who I bought the blade from, but LaserImpact should have one.
You can reach them at 1-888-809-4155 - if you ask for tech support, they
can probably give you instructions on how to do it.
The following may apply if the printer produces quality output but insists
on the error message. Of course, if the printouts are faded, etc., it may
indeed be time for proper maintenance.
(From: Jason Kuetemann (jason.tracey@sympatico.ca).)
Press the 'RECOVER/RESET' button while turning the printer ON. This
will reset the counter.
(From: Steve TR
All of these use the same Canon print-engine.
The toner-cartridge drum is not rotating due to a failed "drum-drive
assembly." You can mark the periphery of the light-sensitive drum to
confirm that it is not rotating.
Remove the top and right covers of the printer. The drum-drive assembly is
a white plastic gear/clutch attached to the gear that drives the toner
cartridge. Inspect for cracks, replace if necessary. OEM part # RG1-1777-
100, Apple Part # 890-0609. You must partially dismount the entire gear
assembly to replace the drum-drive assembly, however, sometimes the new
clutch can be slipped onto the old shaft (which does not wear out): Not all
shafts are identical.
The upper output-rollers deteriorate (perhaps due to ozone) and become
mushy: Replace the roller (Apple "face-down delivery assy." part # 971-
0043 does not fit HP machines, but you can remove the roller and replace
that only.)
Inspect the pickup-rollers. If the gray rubber is smooth and shiny on the
tips of the cams, replace the rollers. Replace obviously-worn rollers as
part of preventive maintenance during other repairs.
When paper feeding begins, a mechanism lifts the paper stack so that the
pickup rollers can grab the top sheet. Inspect the lifting mechanism:
Sometimes parts at the sides become bent, preventing it from working.
The fuser lamp often burns out because the seals fail and let air into the
lamp (resulting in opaque purple/yellow deposits inside the quartz tube).
Replacement is easy, requiring minimal disassembly of the fuser. Rarely,
the lamp-control circuit in the power supply fails.
The laser-scanner motor commonly fails. Replacement is simple but getting
at the scanner requires removing several layers of sheet-metal and circuit
boards, the black plastic cover of the scanner housing, and the plastic
lens: That may take an hour on your first attempt, 15 minutes with
experience. Typically, the IC which drives the scanner motor overheats and
visibly discolors the circuit board. HP-IIP, -IIIP and APLW all use the
same scanner.
Normally, you can hear the scanner motor running; it whines like a tiny
jet-engine starting, a few seconds before the machine begins to feed paper.
Inspect photoelectric sensors, clean with compressed air. If problem
persists, re-seat the appropriate connectors on the dc controller board, or
replace the entire sensor harness. Failure of the circuit board that holds
the contrast control can also cause this indication.
Replace the separation pad (~1x5cm bar with cork-like surface). No tools
required.
The high-voltage terminal on the toner cartridge is making bad contact.
Placing washers under the two mounting-points of the (white plastic) high-
voltage insulator on the cartridge will often extend the terminal enough
for good contact.
The detachable paper-feeder contains two solenoids. Under the armature of
each is a rectangular black foam pad. If the pads become sticky (as in the
HP-II), the paper-feed timing is disturbed. Remove the solenoids, replace
the pads. I use double-sided foam tape, then use naphtha to thoroughly
remove any glue from the upper surface.
I never encountered this problem until November 1995, then saw several
cases in rapid succession: The entire lot of HPIIP-type printers may be
reaching an age where this failure is common, so I now inspect the
solenoids for stickiness as part of the preventive maintenance of any
printer I repair.
Also inspect for broken solder connections on the pins which connect the
paper to the printer.
(From: Edward Klotz (eklotz@www.flash.net).)
The worn D-roller assembly can be replaced in about 15 minutes. May as well
replace the separation pad also (5 more minutes, fixed at least 6 with new
D-roller assemblys from LASER impact out of Texas - about $28 last time I
purchased). Also ozone filters are available, very inexpensive (may save a
repair down the road).
You may be interested to know how I got into laser printer repair. It's a long
story, but here goes...
I was given a non-working Canon LBP8A1. I pulled the case and started fiddling
about and discovered a PAL on the formatter board with a stuck output. The
cure was obvious -- replace the PAL.
Alas Canon didn't like that solution. No parts were available, and no
manuals. At about this time I discovered that the original printer for a
computer that I happen to love - the PERQ - was a CX-VDO -- the same printer
without the formatter. And I managed to obtain the PERQ interface board,
admittedly non-working.
So I totally dismantled the printer in the hope that I could figure it all
out. I had a pile of screws, gears, lenses, mirrors, bearings, etc. And PCBs
covered in unidentifiable chips.
A lot of work with data books (and questions to newsgroups) identified most of
the chips. A lot of hacking about got me enough of the pinout of the CX DC
controller connector to guess roughly what was going on.
Then I had some luck. The guy who'd given me the PERQ card remembered that the
CX-VDO had a ribbon cable from that connector to the outside world. And Bob
Davis, who had obtained all sorts of stuff when PERQ Systems folded, dismantled
his personal machine and ohmed out cables, etc.
Slowly it all went back together. I figured out how to align the scanner unit
using the IR detector I use for testing remote controls. I figured out how to
test (and repair - there was a defective chip and a shorted capacitor) the
main PSU. And I worked out how the status LEDs were connected.
I made up what I thought were the right cables, put it all together and fired
it up. The test page was fine. I was getting there. Put the PERQ card
together, plugged it all it. It sort-of worked. The page was black apart from
a 16 pixel strip at the left. But Bob had been helpful and had sent me info on
the operation of this card. I was my fault. I'd missed out a jumper which
connected a clock to the data FIFO. After that it worked fine.
I now believe that these printers *can* be repaired at home, no matter what
Canon say. And if Canon won't help people, then somebody else should...
Serach at:
Google
Groups for the subject heading: "Repairing plastic paper feed strip in
Canon PC10, etc. or CX laserprinters".
(From: (jollyrgr@mc.net).
If you vacuum toner with an ordinary vacuum, a static charge from the
toner will build up in the vacuum and shock you. Toner works by static
charge. Moving it, as in vacuuming, causes it to give up its charge to
the vacuum. Without having a complete ground throughout the entire vacuum
can cause charge to build up to quite a high potential. Be safe, use a
toner vacuum.
Now if the paper does not get fused, the toner can be rubbed off. This
toner, and any spilled toner still retains some charge. As it is moved
though an ordinary vacuum, charge is transfered to the various parts of
the vacuum. (Much in the same way charge is transfered to a person
walking across a carpet in dry weather). When the charge builds up, it
has to find a way to ground. In the case of the person walking across the
room, the charge is discharged when they touch a metal object such as a
light switch cover or door knob. In the case of the vacuum, its the
vacuum that builds up the charge. When the person using the vacuum
touches the charged portion, the charge is transfered to them (ZAP!!). If
the person is holding the part of the vacuum that is getting charged, they
get charged as well. Only now they get zapped when they touch something
else. A friend of mine worked in a print shop at one time. He spilled a
bottle of toner. Instead of getting the toner vacuum used on the copy
machines, he used an ordinary shop vac. The metal pipe was attached to a
rubber hose. As he vacuumed the toner it was he that got charged. It was
when he touched the grounded portion of the vacuum as he was turning it of
that he got shocked.
Toner vacuums have all their parts grounded (pipe, hose, canister,
motor ect.). These parts are all connected by wires to the ground
terminal on the power cord, shunting any built up charge immediately to
ground. So it is not the conduction of the toner to the electrical ac
line but from the charge the toner itself has.
(From: jlager@tir.com).
I don't know about any fire hazard, but I DO know what that stuff will do
to an ordinary vacuum cleaner from lessons well learned! Toner/Developer
is the finest stuff you may ever see, and will instantly clog all the
pores of a regular vacuum bag. You'll go broke just buying bags. And...
don't wash any of your clothes/rags with hot water that it has penetrated
because it will make the stuff solidify. All my advice is based on
repairing copiers over the years.
(From: Ed Wright (motogump@cris.com).)
The point here is that vacuuming toner, which is carbon black and latex,
will create a static charge. Using a vacuum that is not intended for
this purpose can cause the following. You can blow sensitive components
on circuit boards, expecially bias boards on the developer units of the
larger copiers and the transfer belt power packs of the smaller
machines. Another worrisome possibility is an explosion. I have seen
two old toner capable vacuums ignite the toner dust as it went through
the vacuum. I admit this is a very rare phenomenon but I would think it
would be even more likely in a vacuum not designed for sucking up toner.
I would suggest reading on the side of your toner bottle. Most bottles
caution about disposing of toner by incineration, the stuff is explosive
if the air/fuel mixture is right. It probably wouldn't do much harm but
I bet it would play hell with your office.
(From: Le Baron O. Ferguson" (ferguson@math.ucr.edu).)
Thanks for the response. I think I should state for everyone reading
that I am now convinced that there IS a serious fire hazard. One person
who responded (by email) has seen two of them "light up."
Copy problems can be hard to figure out, but given the evidence the copier
gives you, you can now probably determine what to check.
Black or dark lines are mostly caused by dirty optics (not enought light
getting to the Drum) Blank copies might be a broken corona wire, or even
failed High Voltage board. Black copies can mean a bad exposure lamp (broken
or burnt out) or failed exposure lamp thermal fuse. Black copies with even
blacker images in them could be overtoned (too much toner in the developer
unit) or bad drum ground (the drum cannot discharge {the voltages have
nowhere to go, so they just stay on the drum). Bad drum grounds usually
pull developer, and you get the grit on the copies.
So, I cleaned the optics. That was it! 2 mirrors were CLOUDED with white dust.
Geeeee, do ya think that could do it? ;-)
Light-path in each is going to differ but I'll give you this one as an
example. The 5310 can enlarge and reduce and the table does NOT move, i.e.,
more hoopla under the glass :-)
Legend:
B - Moving assembly containing 2 mirrors: (2) second mirror and (3) third
mirror.
L - Movable assembly containing enlarge/reduce lens.
C - Movable assembly (covered by black sheet-metal cover that also covers
the top of the Lens) containing (4) fourth and (5) fifth mirrors.
D - Fixed (6) sixth mirror that directs light onto the drum.
Layers:
LEV 2 - Glass pane (see LEV 1)
LEV 3 - Scanning layer, exhaust fan to keep dust from settling... Does that
for about 2 minutes and then starts accumulation of very fine dust
on all mirrors. :-)
- Some assemblies are covered to 1) keep the stray light and 2) reduce
dust accumulation - do NOT skip them in cleaning. *Especially* Assy C!
LEV 4 - Structural sheet-metal separates Scanner from drum/toner assembly
below.
LEV 5 - Toner and Paper transport layer
See the document: Notes on the Troubleshooting and Repair
of CD Players and CDROM Drives for appropriate chemicals and materials for
cleaning mirrors (and lenses) In a pinch, a bit of my [clean] 100% cotton
T-shirt works well - followed by a good blow with duster can and soft, [fake]
camel-hair brush. The object is to have a mirror as clean as the minute it
was made.
Apply a half dozen drops of non-detergent light oil onto the felt 'washers' on
any movable assemblies' rods, if present. Might want to dampen a piece of
cloth with oil and wipe the rods. This helps to prevent drips, etc.
I would remove the glass (LEV 2) completely from the machine and give it a
good scrub from BOTH sides with the usual chemicals (ammonia-content is
superior, IMO) for 2 reasons: 1) to keep ALL overspray from rest of machine
and 2) to do a really GOOD job... not half-assed worried about overspray :-)
Don't skimp on corona wires... many machines include a plastic/felt wiper than
prevents injury to the wires, USE IT. I keep a supply of scavenged wires for
times when it goes 'TwhanNNnnnG' for the last time... :-|
Density control - some machines, the 5310 included, have a density adjustment
under the front cover. This is in addition to the DARK-NORM-LIGHT control on
the front panel. I find that after this cleaning, it can be turned back to
somewhere near the middle. This cleaning is often needed if even *that*
adjustment doesn't compensate for crappy copy :-)
After this cleaning, the copy will *overall* have whiter (read: less toner
wasted) background... this will improve contrast and lead to greater toner
cart life. We get them recharged, BTW, for ~$49 or so... New it's $120 from
Office Depot. ARGHHHHHHHHHHHHHHHHH....
(From: Bruce L. Miles (henry31@prodigy.net).)
Two things to try:
If the skyshot print comes out white (it should be entirely black since the
amount of light hitting the drum compared to reflection from actual copy is
nil), and you DID have a latent image on the drum, the prime suspect would be
the transfer corona - it is not receiving the high negative voltage needed to
pull the positively charged toner off the drum and onto the paper. The
culprit could be the corona wire being broken, the corona assembly not making
a good connection into its high voltage socket, or even some weirdness going
on with the high voltage power supply - i.e., supplying proper voltage to the
main corona, but nothing to the transfer corona.
(From: Thierry Thdereck (thdereck@aol.com).)
There also other reason a copier is darker than it should:
So you may have lot of work if you don't know the right setups before
having good copies.
(From: Bernard Morey (bmorey@aardvark.apana.org.au).)
Have you tried cleaning the corona wires? There are generally two modules.
Pull out and clean with cotton-swabs (Q-tips).
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
If your dark grey background is not uniform, you will have to vacuum out ALL
the old toner, and thoroughly clean the roller that transfers it to the drum.
Do not use abrasives, as the surface of the roller is very critical. If this
restores even grey background, you can think of adjusting the bias voltage.
(From: Morton Lee Cohen ya484@@vtn1.victoria.tc.ca).)
I am a former copier tech. that worked on Konica copiers. To get good results
from your copier, a periodical maintenance should be perform on the copier,
every so many copies or once a year, depending on which event occurs first.
During a PM, the optics, corona wires, drum gets cleaned. The Fixing unit gets
cleaned, and serviced. The Developer gets replaced. And adjustments are
performed, if needed only.
The developer transports the toner to the charged area of the drum and
developer gets weak over time. Developer is made up of iron filings.
(From: Jeff Roberts (jroberts@axionet.com).)
Make sure it is the drum that is not cleaning by measuring the distance
between the origional image and the ghost image on the page. that distance
will be the circumference of the drum if that is the cause.
The drum assembly should come out as a unit. Take it out and make shure to
quickly remove the drum from the unit and put it in a dark place so that it
doesn't become light shocked. then look for a blade of some sort, it may be
neoprene or rubber. it is usually on a actuater assembly that can push it out
to make contact with the drum and then retract it back (possibly a
solenoid/cam) this blade does the cleaning by scraping the excess off the
drum. If it is hard or brittle it will have to be replaced but cleaning it
with a 70% solution of rubbing alcohol may be enough. After cleaning it rub
some toner along the edge to re-lubricate it and reassemble and try that.
Also check that the drum unit is not clogged up, the waste toner goes
somewhere and if it uses a sump and the sump is full then it will ghost no
matter how clean the blade is.
(From: Vance Harlow (musk@aol.com).)
On copy machines and laser printers with long life drums (ones where toner can
be refilled without replacing the whole drum assembly) the wiper blade will
usually fail long before the drum does on machines that are not used
frequently or used to print one or two copies at at time. If the service
department is not aware of the problem, or the manufacturer doesn't supply the
blade as a separate part, you'll usually end up getting stuck for a whole new
drum assembly when all that's needed is a wiper blade (this is the rubber or
plastic blade that bears on the image drum, not the felt wand, BTW).
Usually the clue will be that the first few copies are bad, but then quality
improves. If that's what's happening, usually replacing just the wiper blade
will cure it.
Since the blade costs only $10 or so, it can be worth giving it a try before
replacing the drum assembly. This has worked on both my Canon 1010 copier and
various OKI and GCC laser printers.
Finding the blade can take some doing - when I called the local Canon
distributor, they couldn't give find a part number, even though I'd bought a
couple years earlier and knew it existed as a replacement part. Luckily, one
the the service techs was able to dig up the number. OK doesn't list them at
all - they only sell the the whole assembly. But you can get the blades for
most laser printers, and some copiers, from American Ribbon and Toner or
Computer Friends. Since the drum assembly on the old Okis like the 400 and
800 series, and the GCC/Mac versions lists for $250 or so, one frequently runs
into them with bad drums for $0-25. I've revived a half dozen of them simply
by replacing the blade - knowing this trick is like having a free source of
laser printers! the OKI blade pops right in with only minor disassembly; the
Canon is a bit more trouble.
Computer Friends also has a teflon wax for reconditioning drums - they claim
it will protect the coating, fill in small scratches and treble the life of a
throw away drum, and vastly prolong the life of long life drums. I've tried
it so far only on an old 1010 drum, with mixed results so far (worked great at
first, but now copies are getting dirty - don't know if it's the wax acting
up, the drum going despite the wax, or other problems. They also sell the Oki
drums for about $40, and drums for many other printers but not copiers.
If you are lucky, cleaning the optical path: mirror and lens will help.
Cleaning the corona wires is a routine necessity. Use two Q-tips,
one on top, the other on the bottom, of the fine wires and travel the
length. Soak the Q-tips in lighter fluid, my favorite all-purpose cleaner.
Probably the photo-sensitive drum has aged. A sure sign of this is
a difference in density between the first and last copy of a long
(50 copy) print run. This is particularly noticeable after the
copier has not been used for some time.
(From: BRADS TV (bradstv@aol.com).)
I have found that dirty mirrors and optics will cause smudging, dark copies
and generally poor quality copies. Try cleaning these mirrors in the optical
path. NOTE these mirrors are first surface or front silvered mirrors and they
scratch easily. Also look carefully for the complete light path from the
exposure lamp all the way to the drum, you will find several mirrors mounted
at angles to direct the image to the drum . You are right in the fact that the
drum can cause poor copies but cleaning first might be the first step. Brad
(From: Sid Ashen-Brenner (sashen@midusa.net).)
Affordable Photocopiers (http://www.photocopiers.com) may have a Service sheet
for about $15.00 that would contain the codes for your copier. I got the one
for my Mita DC 1255 from them. They also sell parts and supplies at a fairly
reasonable rate.
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
I doubt the cause is a broken corona wire. If this were the case you would
get white copies, instead of black. Check the bias lamps are coming on. They
are a string of small lamps located 'downstream' from the transfer corona
(located at the bottom of the drum).
The first is an intermittent fault which makes it turn out blank
paper, usually on switching on but occasionally during a run. I assume
this is a faulty joint on a circuit board because opening the machine
and slamming the top down usually cures it for the moment.
The second is that the light/dark slider has to be at one end of
its range to get satisfactory copies.
Are these common faults on this model with a recognized cure?
Although it is expensive to run, I seldom need enough copies to justify
purchasing a new one."
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
You're right about the bad connection fixed by the vibration of closing the
cover. Your exposure control is probably at darker than normal to compensate
for aging of the photo-sensitive drum. Some compensation is possible by
adjusting the high voltage or (I prefer) the toner wheel bias voltage. I'm
assuming your corona wires are clean, of course.
(Responses farom: Nate Morrison (nmorriso@plains.nodak.edu).)
Well, that's all they think you need to know. They want you to call the
dealer if the copies are crappy.
The reason you should just toss the used toner bottle is the dust--it is
messy and not good for your respiratory tract.
Some copiers use developer; others don't. How long it lasts before it
runs out is basically in how the copier is engineered. Some gets carried
away every time you make a copy. Pretty soon there isn't enough to carry
toner to the drum anymore.
If you need developer, you can get a kit from the local service shop.
You'll pay plenty, to be sure, but not as much as if someone came out and
did it for you. It might not be a bad idea to invest in a service
manual - I got one for our Minolta for around $20.
Well, that's another of those reasons they want you to hire the
serviceperson at a ludicrous rate. (the local place gets $99/hour!)
You have it pegged.
Another reason is that they want to promote the idea that _their_ copier
is service-free. Telling any prospective buyer that in 50,000 copies it
will require professional service is NOT a selling point. :-) The
copier is designed so you can change toner and paper and that's it.
Anything else is always "see your authorized dealer" in the useless
owner's manual.
The output of the device is very poor: Passages which should
be black are only light grey. If the contrast is turned on
to the maximum the whole sheet gets grey. The copies look as if
there would be only a little bit of toner on the drum. In order
to solve the problem I already checked the optics, the corona
wires and voltages and I filled up the toner. My question now
is whether it is possible that the drum is defect? What else
could cause such a failure?
Since the device is quite old (1988) spare parts are not easy to get,
but the mechanics looks quite well so I do not want to loose the
device."
(From: Copenhagen Cowboy (cowboy@fastlane.net).)
I am a Copier Repair Tech and have a few suggestions for you. First, what does
a Blackout look like? What I mean is, make a copy with the lid up, and check to
see how Black it is. Note to see if there is any "Grit" on the paper. Most
likely if there is no Grit, and the Black area is Grey, then I would suggest
changing the Developer (or you might even have a Developer Drive Problem
[gears and stuff]). If there is a fine layer of Developer on the page, you
probably have a Drum Grounding problem.
My wild guess would be that the frequency changes with low toner or something
like that.
(From: Morton Lee Cohen (cx163@FreeNet.Carleton.CA).)
Probably the disks stir the toner for even dispersion, and break a photogate
to tell the controller PCB that there is toner there. Some Cannon laser
printers/photocopiers use magnetic sensing of the toner level. Most Okidatas
use the photogate sensors with magnetic toner agitators.
(From: Morton Lee Cohen (cx163@FreeNet.Carleton.CA).)
There is toner over a lot of places in copiers, not so much due to
customer problems, but due to lazy service technicians, trying to raise
their average call per day ratios. Service Technicians often get calls to
do Periodical maintenance on copiers late in the day and rush to leave an
account at 5pm, so many overlook non-important parts of the copier to clean
during a maintenance of a copier.
And as far as the toner sensor goes, lots of times toner cakes on
the sensor and the copier never tells the customer that it needs toner,
when the copies start getting light, that the copier starts pulling
developer from the developer tray, and that it gets messy.
Not all copiers are created equal and not all service technicians
are created equal, either also. Some will always be better than others. But
the best policy is always to tell the truth. My telling the truth, you tell
the customer where the problem exists.
Never lie, because if you lie, one always has the remember what
they lied about. From the writers of Star Trek - The Next Generation. And I
practice that in dealing with customers and myself.
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
Your toner/developer wheel bias voltage may be wrong. When light
strikes the photosensitive drum it does not completely discharge it.
The toner/developer bias voltage must precisely match the residual
charge or grey background will result.
Well, I discovered that streaky copies are caused by dirty corona wires
(fixed easily, although 1 unit was held by a screw-in plate, rather than
the usual pull-out method) and that dirty corona wires seems to be caused
by excessive toner deposition (haven't figured that out yet).
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
If the streaks are white, in black areas, clean or replace the corona wires.
If the streaks are narrow black and run the entire length of the page,
replace the soft plastic wiper blade on the drum (and hope the drum is not
scratched). Black smudges are related to the toner/developer purity.
Replace both.
(From: Filip M. Gieszczykiewicz (filipg@repairfaq.org).)
Greetings. Give URL: http://www.europa.com/~tait/copiers.htm
a go. They have all the usual stuff (rollers, picker fingers,
lamps, masters, etc) for many Copiers. My $200 order is in the
mail. :-)
[dig dig]
Drat, they don't list prices for anything but toner for that one.
Their number is 1-503-293-8071 but you might want to try something
closer to home (than Portland, Oregon - 1/2 world away :-) because
the shipping *will* kill you...
The fuser lamp has blown, but it looks as though it might have
overheated before doing so : in two places the tube has expanded
as though it got very hot while under compression from the spring
endcaps. The 47R sacrificial resistor in the fuser lamp relay circuit
(I think it's there to stop the control circuit holding the lamp on
permanently) has also gone open circuit.
What would cause the lamp to overheat ? The thermistor (which was
coated in toner) appears to work : it measures about 300K at room
temperature and falls a few 10K with finger heat, so it's not open
circuit (though it might be incorrect). I'd like to check out the
rest of the copier before buying spare lamps etc. - can anyone tell
me what the thermistor should measure (hot & cold) so I can test the
control circuit and fool the copier into working?"
The thermistor may be working. It sounds like a bad triac or whatever is used
to actually switch power. Get a 300K pot as a sub for the thermistor during
testing.
(From: Adrian Godwin (agodwin@piresearch.co.uk).)
I had a go with this : about 4K fools the control board that the roller is
hot, and allows the rest of the cycle to run.
However, this _doesn't_ cause the heater power to switch off - in fact, only
turning the resistance almost to zero has any effect, and at this point it
appears that the controller attempts to burn out the 47R resistor.
This might make sense, except that as far as I can see there's no way that
the control board COULD turn off the heater power without burning this
resistor : the fuser lamp is powered through a relay which is excited by
the main 24 V supply via this 47R resistor. There's no way that I've seen so
far that the controller can turn off the lamp other than to short out the
relay (which burns the protective resistor). So I wonder if there's no
control -
just a monitor for the copier control board and an overtemperature safety
circuit that disables the fuser lamp (and simultaneously disables themain
motor control triac). This surprises me, as I have a Canon SX-based
printer where the lamp power cycles (though not using a relay, as it's quiet).
(From the editor).
There must be a triac or other mechanism for cycling power to the lamp - its
temperature must be tightly controlled regardless of line voltage fluctuations
and ambient temperature. (--- sam)
(From: FAXFIXR (justdfax@cdepot.net).)
The prefix is always CROP (clear, repeat, zero, pause) and the code for a
U1 reset is 13 then press the copy button. So it would be C R O P 14
This may be necessary if you run the copier past the recommended life of the
drum but still get acceptable performance. You then need to trick the copier
into thinking a new drum has been installed. Other copiers may require
similar treatment as well.
(From: YonyMar (yonymar@aol.com).)
You need to reset the counter inside the copier. When you buy a new drum,
it resets the counter, however it can only do this once. Unplug the copier
and remove the drum and toner cartridge, at the back of the machine where
the drum would slide in look for a small metal lever, push it in with your
finger to reset the counter. The counter numbers are covered by a black
plastic cover.
I have been able to reset the "H1" code before, but this time no luck."
(From: copymann@usa.net).
H-1 means an open thermal fuse on the upper fuser roller. Remove the
cover on the fuser rollers and you will see a ceramic fuse located on the
top plate. Check the fuse for continuity. If bad replace it with one with
the same temperature rating, ( or close to the same ) Sometimes you can
find them a radio shack. If not email me and I will send you one. If you
order the fuse from sharp it is pretty expensive. If the fuse is good
check the lamp in the upper fuser roller or the upper lamp triac. 99% of
the time it is the fuse.
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
The Master is the SURFACE of your photo-sensitive drum. In a brilliant
design concept, Sharp allows you to easily replace a thin (in your case)
cardboard sheet, that effectively gives you the performance of a new drum
at a fraction of the cost. There is no wiper blade, residual toner is
removed by polarity reversal and is re-absorbed in the developer.
Cardboard Masters for your machine are in short supply. Let me know
if you can find some. You may wish to upgrade to an aluminum backed
Master used in model SF760, but they are much more expensive.
I unhooked the components which connect to the logic board - i.e., printhead
and tractor feed.
Is it possible that the problem is in the power supply? If it is, what can
it be? (The bridge rectifier consists of four hefty diodes)."
(From: Bruce A Haugh (yrp456@freenet.mb.ca).)
With the power supply disconnected from the rest of the printer circuits,
blows the fuse, the problem is with the power supply. I have a Raven
PR-9101 (made by Panasonic) that has the exact same symptoms. Turns out
that one of the secondaries on the power transformer has shorted. You'd
need schematics to confirm voltages.
(From: Robert McCallum (simply@sk.sympatico.ca).)
I've fixed quite a few panasonic printers and yes 90% of the time when the
machine is dead, it's one or more of the bridge diodes.
(From: Kerry Messana (messana@capital.net).)
It's fairly simple to diagnose where the problem is originating. If you unplug
(if possible) the output cable from the power supply and it still blows the
fuse then the power supply is at fault. As for what could be wrong, well, I am
not familiar with the particular supply. If it is a linear supply a good place
to start is the bridge circuit. If it is a switching supply you could also
start there but there are more possibilities further on.
(From: John A. McCulloch (advp@notnow.com).)
Another very common problem with the whole Panasonic 11XX series of printers
is the zener diode and pass transistor. When the diode shorts, the transistor
blows, and I mean *blows*!
The 40 and 22 errors normally refer to a problem with the cabling etc. Make
sure that you have it cabled properly. Also, it can be a bit tricky changing
from parallel to serial I/O. Make sure that it is indeed selected.
(From: Paul Grohe (grohe@galaxy.nsc.com).)
Probably by dirt or a paper shreds stuck in the optical path.
A common cause is Liquid Paper. Somebody makes a correction and sticks the
not-yet-dry correction into the fax. Then the still-wet correction fluid makes
a streak on the pickup window as it passes by. Subsequent faxes will now have
streaks.
I had the same problem. It turned out that the ink from a faulty page stamp
had dripped down onto the mirror.
Generally, the paper is moved and the optical path does not move. So if there
is something blocking the optical path, it will show up as one continuous
image, or stripe. The "blockage" can be a paper shred, ink, dust or even a
loose wire.
The image is usually bounced off a long, wide mirror and then into the CCD
pickup somewhere in the bottom of the machine. If anything is in this path, it
will cause that problem.
Open er' up and just look around inside for dirt and loose debris. Then
inspect the *ENTIRE* optical path. BUT DON"T REMOVE ANYTHING!!! You don't want
to mess up any alignments.
If the fax is old, or is in heavy use, you'll probably find that it is in need
of a good cleaning. Clean the mirror and blow out any dust or junk.
Also check the automatic paper cutter (if it has one) for paper shreds.
I suggest you look carefully at the paper feed mechanism. Brother has a
reputation with me for feeding the scanned documents poorly, resulting is
overscanning the same area two or more times, which results in "stretched"
text or graphics. If this seems to match your symptom, cleaning the feed
rollers will probably cure this.
The downside is that a couple of the Brother fax machines that I've had to
clean force you to do an unbelievable amount of teardown work to get to some
of the feed rolls. Fortunately, I don't work on them anymore
(From: MECHSHOT (mechshot@aol.com).)
This problem is a known fault because Brother assembled these units with what
turned out to be defective scanners. They would fail after some time,
typically withing 2 to 3 years. I know, we have 3 that failed and they were
all built around the same time. The good news is Brother will supply the part
(worth about $120) if you pay for the labor (usually around 55-85). Contact
Brother Customer Service (the 800 number is in your owner's manual) and they
will refer you to an authorized service center. Get a bunch (if possible) of
different shops in your area, they charge different labor costs. You must
supply your machine's serial number to see if it is eligible for this program.
Then customer service will make out work order, send it along with part to
center of your choice.
All of the centers I spoke to were aware of this problem and were
confident once fixed, the units were very good and reliable afterwards. Check
local office equipment repair houses for more info too. Hope this helps.
(From: Robert Macy (robert.macy@engineers.com).)
I'm not familiar with the HP LaserJet FAX, but I assume the LJ scans in a page
and then sends it, or copies it. Since the black stripe is unique to sending
or copying a document (does not appear on incoming faxes), the problem is in
the HP's acquisition system.
It can either be the illumination of the page over that small section (no
light, looks black) or it can be a whole section of the linear CCD went out
(the whole section is losing any charges built up, looks black) or it can be
the memory where the image is shifted into (dead RAM section, looks black).
I don't know how the HP illuminates its pages. Is it a flourescent tube
across the page, or a row of LED's? Knowing HP's penchant for reliability I
would almost assume the engineers went after LEDs. And the section that
lights up that 3cm width could have died. However, if it's illumination that
died, usually the edges are "soft".
If it uses flourescent light (remember I said I'm not familiar with this
scanner), then it sounds like the CCD, or memory, has gone funky on you.
If the memory where the image is stored has a section that died, then you
could end up with such a stripe also. Even my ScanMan Plus by Logitech has
occasionally put a black strip on the first 10% of the pixels. To solve that
I have to do a full power OFF reset (not reboot, but full power OFF)
You can look for the illumination uniformity with your eyes. Just make sure
there is no section that's darker by a noticeable amount (not necessarily
black, but just a lot dimmer)
Put a sheet of white paper in the machine and put a scope on the output of the
CCD & sync from the line reset. Make sure that the CCD is supplying active
light information across its whole field of view. If not, you can go from
there.
If the data coming out of the CCD looks good, then it's probably the memory
holding that line. You can probably change the line storage RAM and fix it.
These are just guesses based upon how I perceive the HP LaserJet to work.
Hope somebody that *knows* this unit jumps in with more specific help.
Also sometime it jams paper at the rear. It looks like it cuts the paper off
(the copy or document report) a little short and the roll of FAX paper pulls
it back towards the roll. Thus when the roller advances the paper next time
it gets jammed as it isn't in the feed slot?"
(From: "NO UTN" (utn@pi.net).)
My experience with brother fax:
There are 2 detectors at the output of my Brother Fax, do not know type but it
uses a roll of thermal paper.
Detector 1 simply uses an IR LED and IR receiver to sense the paper.
Detector 2 is on the cutter, when cutting paper the motor turns by means of
a worm-wheel a wheel that moves a handle that lets the cutter move. On the
wheel is a detection switch, there is a ring on the wheel from which one part
is taken away to be able to detect the home position. If cutting starts the
wheel has to be turned in a maximum time, if not the wheel is turned back and
cutting stops. The Fax gave and error message. Solution: put some oil at the
motor and it works again.
Of course, the stuff mentioned below is probably banned now.
(From: uiop@cyberramp.net).
When I worked servicing copiers for Canon, we took the roller out, the wiped
it down with tri-chlor-ethane, which did a great job.
(From: Joseph Patrick (jpatrick@edge.net).)
The best way to clean a fuser is to use a very light coat of silicon oil.
This is used on the heated fuser as well as the pressure roller.
The function of the fuser is to bind the ink to the paper through heat and
pressure it should not accumulate any ink during normal use, it doesn't remove
or collect toner normally, unless the surface is dirty or deteriorated. The
teflon on the main fuser should be slightly shiny much like the surface on a
Silverstone(tm) frying pan.
The item you were thinking of is the drum wiper blade which is a part of the
drum assembly and is usually responsible for streaks / smudges that persist on
the photo drum's surface and make permanent smudges on copies.
I learned of the silicon oil treatment from a 3M service rep. I was using
alcohol in the copiers I serviced up to that time. He showed me the way to do
it by wiping the fuser components with a non linty rag with a little oil on
it until the rollers were completely clean then drying them with another cloth.
The job naturally was done with the rollers fully dis-assembled but in his
case could be done with minimum removal just so the rollers could be turned
and reached without touching the drum assembly, the oil would kill it.
There is also a drum cleaner blade which cleans excess toner off of the
drum between pages. On a regular copier, this would show as streaks or
even a double image that only shows when you print more than one page at
a time.
(From Paul Grohe (grohe@galaxy.nsc.com).)
Been there, dunnit...
The serial interface on the 7550's is...well...weird!
Without the proper cable, the interface will seem "dead" or
unresponsive.
First, you need to use the *male* 25 pin connector, not the
female one (which you may automatically assume).
It requires a specially wired serial cable (you can build it
yourself). A standard modem cable with a F-F adapter will not
work. There are a few handshake lines that need to be wired. Note
that you will also need to get a *female* plug for the plotter
end of your serial cable.
There are also some menu setups required.
HP has a diagram of the needed cable and menu setups on their FTP
site. Get these two documents:
Everything you need, short of RTFM, is in these files.
(These no longer exist. If anyone knows what happened to them or has the
info, please send me mail via the
Sci.Electronics.Repair FAQ
Email Links Page. --- Sam.)
There are some other plotter docs at:
The 7550 suffers from paper pickup rollers that dry/wear out and
have trouble picking up the paper from the tray. If you look at
the rollers, there is a flat portion. The edge of the "flat" part
wears down and becomes rounded, causing it to no longer pick up
paper. Try to keep the paper tray as full as possible.
Overfilling the paper tray will cause it to pick up multiple
sheets, and that can cause a real mess!!
Check the paper feed slot and pinch rollers for shredded paper.
Also, check and make sure the screw that holds the pen carousel
together is tight. If this screw becomes loose, it will cause pen
loading problems.
It's a "helluva" plotter when it works!
If anyone has seen this problem and would be kind enough to share the
fix it would be greatly appreciated."
(From: Darrin Acreman (darrina@profax.com.au).)
In all Oki plain paper machines, 'Printer Alarm 4' is caused by the fuser
section failing to reach the correct operating temperature. The most common
cause is a blown thermal fuse in the fuser section.
Print engine is not one I'm familiar with. It's an 8 ppm engine
that uses separate drum and developer assemblies. The drum
assembly is attached to the top section, which hinges upwards.
The developer assembly is attached to the bottom section, and uses
a replaceable cylindrical toner cartridge similar to that used
in older Canon NP-series copiers. The whole developer assembly
can also be removed.
Paper tray mounts underneath unit, and paper follows an "S" shaped
path through printer, stacking face-down on top. Front panel has
a ~16 char. LCD display and typical button/LED set (ON LINE, Form
feed, Menu, Test, Reset).
(Sorry, don't have the model # to hand. Printer was built in late 1993.)
Printer executes power on self test OK, warms up, and goes on line.
Problem 1: Take it off line and push test, and the motor whirs briefly,
then stops. The LCD display then reads: 'ERROR 74-M: MOTOR'. Reset has
no effect; printer must be power cycled to get it to restart.
Interesting variation: The top section is held down by two large catches
at the right and left sides of the printer. The 'hooks' are released by a
button on the top section. It's possible to get only the right-side hook
to catch, leaving the left side 'loose' and raised by about 1/4 inch. In
this condition, the printer will start up and work fine (except for problem
2 below) for many pages. Eventually, it will stop with ERROR 74-M again.
Pushing down the left side will cause an immediate ERROR 74-M.
I assume there's something binding or sticking a bit in the various rollers,
such that the motor draws too much current or otherwise triggers an error
when the top is latched down. Releasing the top on one edge reduces the
pressure on the various rollers and thus the load on the motor. But I can't
find any obvious points of sticking.
Problem 2: When the printer *does* work, with the cover popped, the leading
edge of the page, down to the first line of print, is dark grey. The grey
is faint on the first page or after a restart or long idle, but uniformly
dark on all pages thereafter. It tends to be striped along the page (varying
darkness as you move left-to-right; uniform as you move top-to-bottom). The
grey disappears at the first line of text. There's also a slight "ghost";
text printed near the top of a page is repeated faintly further down the
page, apparently displaced by one rotation of the drum.
This seems most likely due to a bad cleaning blade or clearing corona.
Anyone have any suggestions other than replacing the drum assembly?
Also, anyone recognize this print engine, so I can track down
parts via sources other than Packard-Bell?"
Dor HP Laser printers, try:
I've been recycling cartridges for a few years now.
Summit Laser Products (formerly
Chenesko Products) has comprehensive product and technical information.
Although they are not aimed at hobbyists and do-it-yourselfers their
emphasis on service is refreshing. Currently their minimum order is $60
with about 6%discount above $250. They can probably point the private
consumer to stores which do handle single-unit sales.
Another distributor for the pro is Oasis Imaging (1-800-322-8992, New
Hampshire for regional office).
Here are a couple of places who used to handle small orders. I haven't been
in touch with in years, though:
Steven Michlin's LaserLand (orders 800-60-TONER) in Michigan
Computer Friends (orders 800-547-3303) in Oregon had "starter kits"
Finally, RECHARGER Magazine intended for
the remanufacturing industry only. Each issue is full of products and
companies.
I've heard good things about a company called 'The PrinterWorks' for HP
(and other Canon) laserprinter parts. They have a web page with an on-line
catalog and search facility at:
All kinds of parts are available even down to that little brush stored inside
your HP LaserJet Series II: The SX engine parts catalogue shows that the part
on page 350 (feeder assembly) as part number RF1-1177-000. It costs $1.23 plus
shipping. Or, that 27/21 tooth fuser driver gear (RS1-0287-000). It costs
$1.10 in quantities of 1.
(From: Dave Lee (leedj@uwec.edu).)
I have used them for the last 4-5 years for HP Laser and ink jet parts. They
also do some Panasonic parts. Great tech support, good prices, same day
shipping, etc. They have treated me very well. Also, service information
on a variety of printers.
(From: Paul Strider (pstrider@phys.ufl.edu).)
(From: George Hurley (ghurley@voicenet.com).)
They'll even fax or mail you a diagram of printer subassemblies so you can
identify the exact part you need.
(From: Dave Noseworthy (davenos@pesl.com).)
(From: SargW1 (sargw1@aol.com).)
(From: Sid Ashen-Brenner (sashen@midusa.net).)
You may be able to get a Service Sheet with the error codes (among other
information). They also sell parts & supplies.
Try this link for HP and other printer parts:
They have a free tech line. Much better than HP.
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
There are 3 fuses/breakers to my knowledge:
The mains circuit breaker is in the AC block (right hand side of the
fuser). It's hidden by the fan duct, but that's quite easy to remove if
you have the casing off. The breaker is a little rectangular object with a
button on top, on the lower PCB. Press down the button and try again.
The Low Voltage PSU contains the other 2 fuses. One is in the mains side,
and is a normal 20mm cartridge fuse. If you remove the casing and the
bracket round the front of the printer (6 screws), you can see this fuse
on the PSU PCB. This fuse is a listed spare part at 'the Printerworks',
which is strange, since the only time it should fail is if there's
something majorly wrong with the PSU, and no other PSU spares are
available.
The other fuse is a thermal one, clamped to the heatsink in the top right
corner of the PSU PCB (looking at it from the component side). This one
protects the 24 V pass transistor that on the same heatsink. I've never had
to replace this one, so I don't know what the rating is.
If all the fuses are good, then you need to do some more troubleshooting.
Firstly, check for mains at the 2-wire connector to the LV PSU. If that's
missing, then you need to remove the mains input block (easy, once you've
removed the fuser), and sort it out. It's _very_ simple, and should pose
no problems.
If mains is present at the input to the LV PSU, check its outputs. Remove
the base cover, and sit the printer on the right hand side. The LV PSU
output is on the 14 pin connector in the middle of the engine control (DC
controller) PCB. The front 2 pins are ground, the next 2 are +5 V, and the
rearmost one is +24 V. If they're missing, you have a PSU problem.
Good luck in that case - Canon flatly refused to supply me with any spares
for the PSU. They claimed that it would be dangerous to repair it. Quite
why it's more dangerous than any other SMPS that I've worked on remains to
be seen.
(From: Patrick Mulvey (pmulvey@li.net).)
A number of the fuses that are in the laserjets are hard to spot. There is
a small component on the boards that is a small black disk. You will have
to follow the wiring from the fuser back to the board and look for this
small component (fuse). I have on one occasion lost power to the paper feed
motors installing a card access device (defective harness shorted the
motor to ground), and found the "fuse" after looking everywhere. Looks
like a disk cap but leads are on opposite side of the disk and its mounted
parallel to the PCB. Hope this helps...
I have had good luck purchasing manuals from a company called "Wright-Moore
Corp, P.O. Box, 66019, Indianapolis, IN. 46266-6019. I have bought a ton of
Toshiba parts and manuals for less than a quarter what any Toshiba repair
parts distributor quotes and I know that they are a distributor for Mita. The
only possible problem is that they want to deal with someone that has a
business license (read resale or Tax ID certificate). If you know someone that
will let you use their name and / or address, Wright-Moore doesn't care if it
is copier or laser printer connected. They do have an 800 number which I don't
have in front of me but is listed with 800 directory assistance.
(From: Joe Wagg (jwagg@fs.cei.net).)
Good luck. Even the Okidata service manuals don't have schematics. The
easiest and most cost effective way I know to fix these printers is to
send the board off to be repaired. I'm not sure about the price, but
the logic board for that model is probably around $100, assuming you
send yours in to be repaired. This way you get a known good board with
a guarantee. I suggest using Laser Impact, address below. Hope this helps.
(From: Uncle Monster (unclemon@bellsouth.net).)
Try "Ted Dasher & Associates" (http://www.dasher.com), 1-800-638-4833. Ted
sells refurbished HP equipment out of Birmingham, AL, He may sell you the
parts, info or a trashed printer with the parts you need.
-- end V2.68 --
HP LaserJet II just dies and no sign of power after a short while
(From: Larry Sabo (sabo@storm.ca).)
"I have an HP LaserJet II that will just die after a short time. There are no
power lights, not even an error message. If I leave it for a short time it
will come back on after a power cycle. It is totally random."
HP LaserJet II with dark bands on first page
(Problem and solution from: Ken Eckert (eckert@sfu.ca).)
"The problem is a dark horizontal band starting at line 1, about 1/2" wide,
indistinct edges. Repeats down the page at same length as the optical drum
circumference. Problem is present only on page 1 of a print job. All other
pages are clean. When the engine is stopped at the beginning of the print
process a large amount of toner is present on the OPC in a band. Band gets
darker and larger the more time between successive print jobs is incurred.
HP LaserJet II output jam
"I found a junked HP Laserjet II which initially jammed pulling in the paper.
I have fixed that. It still jams on the output, though. It prints nicely,
so it seems worth fixing. If I open the back tray, the sheet exits 90%
before stopping with the "paper jam" error. With that tray closed, I get the
accordion paper jam in the fuser area. I do not detect any rotation of the
upper rollers to feed the paper out of the top. When opened, I can roll
them by hand easily. I see no obvious gear wear or broken teeth. I also see
deep scratches in the grey fuser, which is probably unrelated. The toner
does not have any fusing problem that I see in a band down the page."
HP LaserJet IIp won't go past 'warm up'
"I have an HP IIP that goes through the "05 Self Test" mode but hangs
when it gets to "02 Warm Up." The only thing I ever hear run is the fan.
I am not getting any error codes otherwise. If I try to send a print job
to it in this state, it seems to take it and the On Line indicators light
up, but it won't print. Based on what I've read in the FAQ and in the
archives, I'm guessing it is the DC Controller. I re-seated the connections
going to the DC controller PCB and the power supply and everything else
visually looks good. I do not have a service manual for this unit.
If hung on "02 Warming Up", trouble may be caused by cables on the door
wear and tear. Also look at DC Cnt PCA, dual I/O, formatter PCA. Now
also look at the solenoid for the MP pickup roller assembly. This can
cause the 'hung 02 Warming Up' error if an open occurs in either the
solenoid cable, or solenoid coil. To check, remove the formatter PCA in
order to access the DC Controller PCA. Locate J209 on the DC Controller;
pins 1 & 2 are the solenoid. Measure across the top of these pins, the
correct reading is 200 ohms +- 10%. Replace the paper path door cable
assembly, Part #RG1-1608-000 if the solenoid has high resistance.
Totally blank printout on laser printer or copier
(From: Ed Paolo (edpaolo@intac.com).)
Bearing replacement on HP LaserJet II to fix error code 41
(From: Andreas Mohr (a.mohr@mailto.de).)
HP LaserJet series II - error code 50 Service and clicking
(From: Peter Strezev (jup001@airmail.net).)
Notes on HP LaserJet II error code 50
(From: ROO7L@aol.com.)
HP LaserJet II - Top of the line printing shifting in multipage printing
(From: M K Ramadoss.)
HP LaserJet II bad bearing sounds
This also applies to many other laser printers using the Canon SX or similar
print engine.
"Developed frequency-changing whine of bad bearings. Not really sure whether
a fan motor or main motor."
HP LaserJet II fuser overheating
(From: Glenn Allen (pclogic@xtra.co.nz).)
HP LaserJet II triac replacement
(From: John (jneff@uidaho.edu).)
HP LaserJet Series II intermittent
"My new (to me) HP Laserjet Series II printer seems to have a power supply
problem, although its previous owner said his supplier/servicer suggested
the problem was 'probably due to a fryed mainboard' and promptly sold him a
new printer. Lucky me. :-)
HP LaserJet IIP printer error code 12
(From: Michael (action@netdoor.com).)
HP LaserJet IIP with 12 Open or no EP error
"I have tried to reseat the EP-L cartridge and opened and closed the fuser
door many times, but can't seem to get this printer to work."
HP LaserJet IID Error 13
(From: John H. Meyer (John_Meyer@compuserve.com).)
"LaserJet IID gives Error 13 message immediately upon warmup. (This is
paper jam message.) The paper path, however, is totally clear. I've
taken things apart and cleaned the exit sensor and paper path. Unit is
quite clean. I've downloaded information on Error 13 and have tried
everything except replacing DC controller card ($200-$400 part). I took
the unit to two different repair places. One tried swapping out the
fuser assembly -- that didn't help, and that was all they were willing
to do for their free diagnosis. MicroAge charge me $$ for a few hours
troubleshooting and tried swapping out the main motor. No help. They
also claim to have electrically checked the exit sensor. They said that
the only thing left was to replace the DC controller card, but they
didn't have one to swap in, so I'd have to pay up-front for the card.
HP LaserJet IIP and LaserJet series 2 error code 52
"I have a HP LaserJet IIP, which does not print, but displays Error Code 52.
Don, a man who is willing to help me fix mine, has a HP LaserJet series 2
that works. How similar are theses two machines? Is there any chance that
one can swap parts to find the problem?"
HP LaserJet II scanner information
(From: Jon Fick (JFick@pcilightingcontrols.com).)
HP LaserJet IIP error code 51
"I have here a HP Laserjet IIP which gives errocode 51. The manual
says something about a beam-detection. Do you guys 'n girls think this
is to repair for relatively little money?
HP IID error code 50
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
HP LaserJet IIP+ error code 50
"My owners manual tells me that if this error persists after a 15 minute
power interruption then service is required.
Is it feasible for me to perform this service myself?
What is the risk factor that my printer will be FUBAR if I attemp this?"
HP LaserJet IIP - 52 error
"The problem with the machine is as follows:
"I have a HP Laserjet IIP printer that no longer works and I need some help
diagnosing. The printer does not print any text pages but instead gives an
error 52 on the LCD screen. The owners manual says that an error 52 is a
scanner malfunction. However the authorized service center said that this
error was a memory error. The cost of having them fix the printer is more
than the printers worth."
J212 on the dc controller
------------------------------------------------
Pin 1: Gnd (blue)
Pin 2: Gnd (blue)
Pin 3: +24 * (red)
Pin 4: +24 * (red)
Pin 5: Gnd (blue)
Pin 6: +12 (orange)
Pin 7: Gnd (blue)
Pin 8: +5 (brown)
Pin 9: Data signal (yellow) (shouldn't matter)
* Paper path door closed or pwr supply interlock defeated
HP Laserjet IIP error 52 - chip replacement
(From: Jon Fick (fickpci@aol.com).)
Laserjet IIP PS board
(From: Brian Mathews (icontech@volcano.net).)
HP LaserJet III problems
"This LaserJet III has me stumped. It has a persistent error 50. I tried
everything in the service manual, but to no avail. If anyone has an idea
how to fix this, it would be most welcome"
Smudged vertical line on HP Laserjet III
(From: Dan Bourque (danbou@nbnet.nb.ca).)
Shifted print on HP LaserJet III
"The LaserJet III in my office has acquired the annoying habit of shifting
its printed output about half an inch down on the paper. This sometimes cuts
off the page numbers. It typically will never happen on the first few pages.
Once shifted, it stays that way, until I turn it off. I'm kind of clueless,
the manual doesn't mention anything like this."
HP LaserJet III powers on but appears dead
"When I flip the power switch on, I can hear it power up, but the none of the
lights comes on and the LED panel is also dead."
HP LaserJet III cold fuser
(From: Flemming (flemming.gottsche@get2net.dk).)
HP LaserJet III paper jam
"I have two LaserJet IIIs that complain about a paper jam on power up,
right after the self test (i.e. before I've even had a chance to send
anything to the printer)."
HP LaserJet III paper feed problem
My LJIII wouldn't feed paper past the registration assembly. Sounds like a
mechanical problem right? No, it was not mechanical but rather it was
electronic problems. At first I replaced the two drive transistors on the
solenoid board thinking that one of them burned out but that didn't solve the
problem.
HP LaserJet III error 50
"My HP Laserjet III is giving a "50 Service" error. So something is wrong
with the fuser. But the lamp is not burned out. Also, the fuser roller is
pretty clean.
Notes on HP LaserJet III error code 50
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
Pins 1,2 T101 current sense transformer secondary
Pins 3,4 RL101 relay coil
Pins 5,6 Solid State relay (SSR101) input (6 +ve)
Pin 7 Fan control
Pin 8 Fuser drive from the DC controller
Pin 9 Ground
Pin 10 +24 V (input)
Paper jams on HP LaserJet IIIP
"More and more I get HP Laserjet IIIP printers here with all the same
problem: 13 Paper jam. Every time I look at the driving-mechanism and
move it with my hand, but it all seems to work fine. I suspect there's
a common cause to all this. I think it's got something to do with the
electromagnet in the tray, but I'm not sure."
HP LaserJet IIIP power up problems
"I have a HP Laser Jet IIIp, The problem is when it is switched on, the
printer can do one of two things; the panel lights up and displays 05 Self
Test and then switches off after around 3 Seconds, and other times nothing
happens at all."
HP LaserJet IIIP - error code 52
"I have inherited a dead HP LaserJet IIIP printer and would like to hear
your thoughts on its chances.
HPLaser Jet IIIsi - 'User Maintenance' message?
"What cause a working HPIIIsi coming up with 'User Maintenance' message
in the lcd window. If you pop up the cover and reclose, the message goes
away and printer keeps on printing fine."
HP LaserJet 4 - intermittent error code 50
(From: Brian Mathews (icontech@volcano.net).)
HP LaserJet 5L grabbing more than one sheet of paper
(From: Shaun Harwood (shaun.harwood@virgin.net).)
HP LaserJet 5 SIMM codes
(From: David B. Gustavson (dbg@SCIzzL.com).)
Pin 70 69 68 67
-----------------------------------------
o o o o treated as an empty slot
o o o g 53.00.02 error
o o g o 53.00.02 error
o o g g 53.00.02 error
o g o o 53.14.03 error
o g o g 16 Meg RAM
o g g o 2 Meg RAM (=LJ5 70ns)
o g g g 4 Meg RAM
g o o o 53.14.03 error
g o o g 16 Meg RAM
g o g o 53.14.03 error
g o g g 4 Meg RAM (=LJ4 80ns)
g g o o 53.14.03 error
g g o g 16 Meg RAM
g g g o 53.14.03 error
g g g g 4 Meg RAM
HP LaserJet random behavior - no ground
Aside from surge supressors not being effective (to the extent that they ever
are) without a proper safety/earth ground, here is another example of possible
symptoms:
Determining if HP LaserJet partial print problems are scanning or logic
This would apply if, for example, an HP-LJ3 prints only left side of the page.
LaserJet IIID and others: paper not picked up correctly
"The printer will print perfectly on both sides if the paper is fed into
the sheet feeder. If the paper is fed from either of the paper
cassettes, the paper not picked up from the cassette. There is a mark on
the paper where it appears the roller has been rubbing on the paper."
Laserwriter LS
"I have a Personal Laserwriter LS; am getting 'fuser assembly
malfunction' error. Does anyone have experience w/this, know the
likelihood that I need to replace the entire fuser assembly, or how I
can find out? Also, is there a place to get a used assembly, and is it
difficult to make the repair myself? Stores charge $200 parts and
labor for the replacement, and this printer's not worth that
investment."
Apple technical information
The following Web site provides links and a search capability for Apple
computer products including Apple printers:
Apple Lserwriter I/O
"I just picked up an Apple Laserwriter II NTX which appears to be working.
The problem is I need to find out what this thing has for I/O, and what
the dip switch settings are. It appears to have a 50 pin centronics
connector, along with a DB25, an appletalk port and one other port."
Switch1 Switch2 Function
---------------------------------------------------------
Up Up 8 pin AppleTalk (Serial Port Disabled)
Down Up 25 pin RS-232 and 8 pin RS-422
Serial Ports 1200 baud
Up Down 25 pin RS-232 and 8 pin RS-422 *
Serial Ports 9600 baud
Down Down 25 pin RS-232 serial port 9600 baud;**
pin RS-422 serial port 0 baud
Switch3 Switch4 Function
-----------------------------------------
Up Up PostScript Batch
Down Up Diablo 630
Down Down HP LaserJet
Up Down PostScript Interactive
Switch5 Switch6 Function
----------------------------------------
Down Down No Handshake
Up Up ON/XOFF
Down Up Etx/Ack
Up Down DSR
Apple LaserWriter and LaserWriter Plus paper jams
(From: Ralph Wade Phillips" (ralphp@techie.com).)
Apple LaserWriter prints double/repeated images
The characteristic is faint repeated printing a couple of inches down the page
as well as from the previous page.
Apple LaserWriter IIg runaway scanner never stops
(From: Dave Lee (leedj@uwec.edu).)
Apple Laserwriter IINT error codes
"Where can I find the meaning of the flashing error codes on a Laserwriter
II NT printer? It is flashing both the paper jam and the paper out light.
The fuser doesn't heat up."
Apple Laserwriter IINT 'clicks' with intermittent fuser error
"I have a LaserWriter IINT with an intermittent fuser error. When the printer
is switched on, sometimes it cycles normally and works fine; but sometimes,
the startup cycle sound is followed by a soft click, and a few moments later
the green light gives way to double blinking red. I have attached a voltmeter
to the fuser lamp contacts; when the soft click is heard, no voltage reaches
the fuser."
Diagnosing a blank vertical strip problem on Apple Laserwriter IINT
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
Upgrading Apple LaserWriter to LaserWriter Plus
It may be possible to upgrade your Apple LaserWriter if you have a partially
dead LaserWriter Plus.
Toner All Over Paper on Various Brother Laser Printers
(From: Robert Wilson (rfwilson@intergate.ca).)
Resetting "REPL.DRUM" error on Sharp JX-9460
This will probably work for other laser printers as well though the details
may vary. Use at your own risk!
TI MicroLaser Plus laser printer reports 'Main Motor Err'
"I have a Texas Instruments Microlaser Plus laser printer which after I turn
it on, reports that the self-test passed but then displays an error on the
LCD: 'Main Motor Err'.
Fuser problem/printer parts
"I have a ti-microlaser printer that worked great until a gear in the
fuser assembly cracked. This gear drives the rollers in the fuser. If
anyone can tell me if there is a place to get used parts or a kit of the
common parts that fail in the fuser etc. it would be a great help. Also
looking for any other info on this printer such as: schematic, user manual,
and part numbers for the photoconductor unit, developer unit and toner
cartridges."
Swapping fuser parts
"I have a couple of Scrap Brother HL-8 Laser printers.
Panasonic KX-P4410 CHNG DRUM error code 027
(From: David Moisan (dmoisan@shore.net).)
Panasonic 4420 laser printer error code E31 and other comments
(From: Al Savage (asavage@iname.com).)
Copy counter fuses
"I have a Panasonic KX-P4420 laser printer. It locked up with a message
about 36K service.
Laser Printer info
"Is there any info available on the net on how Laser Printers work, & how to
fix them? I've worked on a few, & am learning the hard way, but could use
all the help I can get."
Strange running time meter/copy counter
"I have disassembled (read: cannibalized for parts) an old Cannon laser
printer a few months back. I found a mysterious part in it. Perhaps
somebody can enlighten me as to what it was thrown in for...
Laser Printer prints heavy on one line about 2 inches from bottom
"What could be causing my Brother HL8e laser printer to smear/or blur one
line of text about 1-2" from the bottom of the page. At this point, 90%
of the page has already fed through the printer with no problem. Can't see
any botched labels or other obstructions. It doesn't always do it, but
at least 50% of the time if there is text at that point on the page,
there will be a heavier print on that line. I don't know if you would
call it blurring, it's kind of like it's printing twice double at that
point. Is it the rollers? Which rollers should I replace?"
Image tilted/skewed/crooked on old IBM laser printer
"I have an ancient IBM Laserprinter E P/N 1039229 that has an
aggravating problem: the printer prints fine except that the image
is skewed on the page. There are no problems with the image itself
other than the fact that it is a little crooked. I suspect that the take
up wheel (D-shaped with rubber coating) is the culprit because the
paper does not jam. Anyone have any experience with this? I don't
want to replace the wrong part!"
Fuser Roller collects toner on laser printer
"I have an AST TurboLaser/PS (also known as an DEC LN03, a Brother, etc, etc.).
When I bought it someone had let a ring of melted toner collect on the fuser
roller until it had burnt through the coating and ruined the roller.
So I replaced it and ran a few thousand copies through the printer. Now I
notice that the roller is beginning to collect a bit of toner again. Just
how does someone clean that roller without pulling the coating off? I tried
the usual wiping with a paper towel and that removed some of it but there is
still a hint of it left and a few more copies begins to let it accumulate
again."
HP original laser printer 2686A: bargain or boat anchor?
"This printer is (i'm told) supposed to print a test page full of assorted
characters yet only prints multiple parallel lines. Also, i'm unsure of
the proper hookup to Win95, parallel or serial interface. To clarify, I
bought this thing used from someone who 'knew nothing about it' and the HP
web site volunteers little information."
Okidata printer that's streaking
(From: Dan Fraser (dmfraser@rogers.wave.ca).)
First page smudges on OKI OL400
"Sounds like my second hand (sorry, previously owned) OKI OL400 has a
problem with the fuser roller, too. Up till now I've just printed two
first page copies of everything I needed 'clean'.
Resetting 'Replace Drum' message on OKI OL400
Laser printer test equipment
At least one company offers a device specifically for testing of laser
printers. This is obviously not going to be something you will want if
you deal with 1 laser printer every few months. However, where dozens of
printers a week are involved, check out: http://www.LaserWizard.com/.
Frank's repair notes: HP-IIP, HP-IIIP, Apple Personal Laser Writer
(From: Frank Reid (reid@indiana.edu).)
Tony's entry into laser printer repair
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
Repairing plastic paper feed strip in Canon PC10, etc. or CX laserprinters
(From: Curtiss Priest (BMSLIB@MIT.EDU).)
Photocopiers
Note: also see the chapter on Laser Printers as the operation and problems of
the two types of equipment are very similar.
Warnings about vacuuming copier toner
"I know there are special vacuum cleaners for use in picking up toner in
laser printers. What is the problem with using a cheap ordinary vacuum
cleaner? Is there a fire hazard? Thanks for any comments."
Comments on copy problems
(From: Copenhagen Cowboy (cowboy@fastlane.net).)
General image quality problems - Clean the optics first!!
The office here has a Xerox 5310 (Rebadged-Sharp) and it's been getting
progressively worse with respect to overall image quality. A new drum ($140)
has helped but things go down the crapper too fast for comfort. (~90 thousand
copies, 4th drum now.)
ddddddddddddddddddddddddddddddd LEV 1
========================================= glass LEV 2
[1 ] \2 LEV 3
A[ \ : \ ..
[ ] \B ..
/ ..
4/ ()L /3 ..
C / () / ..
-----| |--------------------------------------- LEV 4
5\ \6 LEV 5
\ \D ..
[P] .--. ..
/ \ ..
| DRUM | ..
dddd - represents the paper document you are copying
A - Moving assembly that holds the exposure lamp and (1) first mirror.
P - Erase lamp assembly.
LEV 1 - External to the copier, look for whiteout and layers of smudges.
Diagnosing 'blank copy' problems
"I have just cleaned a Sharp SF 755 which was quite dirty but now will
not copy at all! No error codes paper hot on exit, all seems well but
the paper is blank."
Copies too dark 1
"I have an old Savin model 7010 copier that works just fine
except it prints to dark. I have to keep the "lighter darker'
control to max "lighter". I have replaced the (expensive)
OPC cartridge and cleand all the wires and mirrors etc.
It works best right before it runs out of toner, of which
it uses up to fast. Any info will be appreciated!"
Copies too dark 2
"Canon NP-2015s ... prints very dark, with "water stained" appearance. All
controls full light gives a 'readable' copy with a dark grey background. I
have been told everything from 'wrong toner' to moisture in the toner. The
guy who brought it to me doesn't know. Before I vacuum out the toner & stick
a $25 cartridge in it, could this be a bias problem?"
Copies too light
Aside from a misadjusted 'darkness' control, improper voltages, dirty corona
wires, and worn drum, don't overlook the trivial: your paper may be incorrect
or damp.
Previous copy doesn't erase from drum
"I recently purchased a Mita DC-111 copy machine, and I finally
it to make copies, now I have on big problem. When I do more
than one copy, the drum doesn't fully erase itself, thus leaving
ghosted images on the remaining copies that are made. I don't
know much about copiers, and I really just lucked into getting
it to actually make copies. Any help would be appreciated.
Copy quality degrades with use
(From: Lionel Wagner (ck508@FreeNet.Carleton.CA).)
Copier error codes
Most modern copiers produce an error code of some sort when, you guessed it,
they detect an error. However, there is no standardization. So, other than
posting to sci.electronics.repair or checking this FAQ, how does one determine
their meaning?
Canon PC25 copier problems
"The lamps goes on my Canon PC-25 but I get nothing but black copiers.
I'm told the problem could be a broken corona wire. Where is the corona
wire located? What does it look like? How do I determine if it's broken
and how is it replaced? Thanks in advance."
"I have an elderly Canon PC25 Copier, which still runs well apart
from two problems.
The mysteries of developer
"My owner's manual never mentions developer anywhere. This copier uses
toner cartridges which mount above the dispenser and drop toner into a
mechanism which distributes it to the drum. There is a white plastic
bottle which catches excess toner and eventually fills up and needs
replacing. They say to replace the bottle, but I just empty it, wipe
it off and reinstall it. Only the toner cartridge and the bottle are
mentioned in the useless owner's manual."
"So, if my copier needs developer, how do I obtain it? Where does it
go? I suspect that I purchase a bottle of these 'iron particles' and
dump it into the slot where the toner drops into, but I don't want to
do *anything* until I know the right thing to do."
"Why is this rather simple maintenance procedure kept a secret from the
owner? Is Mita trying to make money for their authorized repair
outlets?"
Problems with Ricoh copier
"Some time ago I got a big and heavy RICOH xerox copier and I have got
a problem with it:
Toner sensors?
I took one of those apart and found something that looked like a piezo
element with 3 wire connections to concentric rings. I looks to me like
some sort of resonator but I have not attempted to analyze the circuit.
Comments on copier cleanliness
Copiers are about the ickiest equipment to dismantle with all that
black toner over everything!
Gray tinge on Xerox 5260 Copier
"Earlier this year, I inherited a Xerox 5260 personal copier. It works
well except all the copies have a grey tinge to them, even when the
auto-exposure control is set to light. The grey background is visible
over all the page, and gets noticably darker when the auto-exposure
control is set to dark. Is it time to replace the copy cartridge?"
Streaky copies
(From: Bernard Morey (bmorey@melbourne.DIALix.oz.au).)
Toshiba parts
"Can anyone tell me where to get old / deleted spares for Toshiba
photocopier model No BD-3110, or where to get the following for the
mentioned copier.
TEC High Voltage Unit (HVT-T)..Model No AFT-375-A
Canon PC20 cold fuser
"I'm trying to repair a Canon PC20 copier, on which the main problem
is a cold fuser.
Broken Sharp Copier
"My Sharp copier is dead again, it's an old one. It is flashing "U1"
which I think means internal lithium battery is dead, but it won't
reset. Somebody emailed me the secret code once, but I have since
Resetting Sharp Z-25 copy count
Sharp SF-71 copier will not reset
"I have an old Sharp SF-781 copier which will not reset. The diagnostic code
"H1" is flashing on the display and the copier will not reset to the
operation condition, using the keyboard clear sequence.
Sharp SF-7100 copier drum replacement
"I have a Sharp SF-7100 copier. When I call about a replacement drum, people
tell me it uses a Master. What is a Master? Can I install it myself. Does
anyone have a service manual for this copier?"
General Problems
Panasonic 1124 power supply problem
The following, of course, also applies to many other printers and other
electronic equipment, for that matter.
"I have a Panasonic 1124 printer which keeps blowing the only 250V 3A fuse
on board. The fuse burns as soon as the power is turned on.
Cannon LBP-8 A1 Printer 40 and 22 errors
(From: GTRIST (gtrist@aol.com).)
Fax Machines and Scanners
Fax/scanner striping
"One of my fax machines produces some black stripes in copy mode and on the
documents received on another machine. Are these stripes caused by a
malfunction of the optical diodes bar, some other electronic failure or by
dirt?"
Brother Fax machine feed problems and cleaning
(From: (Al Savage) asavage@iname.com ).)
Brother IntelliFax 950M transmits black messy lines
"I have a Brother IntelliFax 950M plain paper fax that transmits with black
lines or dots. When making just a copy the prints are just as bad. The
prints are tiny square dots that make up these lines. It looks like
digital problems and not dust on the lens. I'm not very familiar with
plain paper faxes. It looks like a scanning failure. I'm guessing at a
scanner or some other circuit board. Receiving faxes are ok. Has any one
had experience with the Brother Intellifax 950M? Also, Brother has a part
called a NUC printed circuit board. Would this be some sort of scanner?
Hewlet Packard LaserJet FAX (HP C1740A)
"This machine is copying and sending fax with a line about 3 cm across
straight down the paper. This is a thick black colour. Any ideas as to
the cause? I have already checked that there is no paper jam or any block
to the sensor.
Paper sense problems with Brother Fax
"I have a Brother 470 FAX machine that appears to have a broken micro-type
switch that detects there is paper WITHIN the front feeder.
Miscellaneous Problems and Procedures
Cleaning the fuser roller
Streaks on laser printer output
(From: Bruce Tomlin (btomlin@crl.com).)
HP plotter communications problems
"I'm repairing HP plotter 7550 and there are some
chips that I suspect to be broken. They are related to
serial communications ( thats what is broken). The chips
are labeled as 1820-3321 and 1820-3322. I suspected that
they could be 1488 and 1489 but changing them did not fix the problem"
Okidata FAX machine - Printer Alarm 4
"I am currently working on a Okidata fax machine Model Okifax 2100.
The display reads: PRINTER ALARM 4[TEL], CONFIRM AND 'STOP'
Unresolved Problems
Packard Bell laser printer - strange bug
(From: Jordin Kare (jtk@s1.gov).)
"Just picked up a used Packard Bell laser printer with some problems and
could use help...
Service Information
Printer, copier, and fax Web sites
Unfortunately, these tend to come and go! The following include some with
info, error codes, message boards, and links. Some make their moeny on
parts and repair kits to beware of those that may be overpriced.
USENET newsgroups
In addition to the USENET newsgroup: sci.electronics.repair, there are a
variety of computer related newsgroups including comp.periphs.printer,
comp.laser-printers, and comp.sys.hp.hardware which are relevant to printer
related problems. However, sci.electronics.repair is probably still best for
hardware type print problems (not drivers or applications).
Copier forums
This is a newsgroup style bulletin board for copier selection, troubleshooting,
repair and appears to be a good archive if you should need to find something
not in this document - hard to believe, but possible :-). However, it is
separate and distinct from any Usenet affiliation as far as I can tell.
HP LaserJet parts
(From: Dave Lee (leedj@uwec.edu).)
Laser printer cartridge rebuild info
(From: terwes11 (terwes11@email.msn.com).)
Printer parts
(From: Tony Duell (ard@p850ug1.demon.co.uk).)
HP DeskJet Parts
(From: Jeff (jkinc@erols.com).)
LaserJet II: Where is the fuse?
LaserJet III: Where is the fuse?
"I am looking for the fuse of an HP LJ III. I shorted an exposed wire
to ground at the fuser unit with my screwdriver. It was exposed
because someone broke the cover of the fuser unit. Now the printer
gets no power, the front display does not light, the fan does not come
on. I looked for the fuse in all obvious places to no avail. Any
hint is appreciated.
Copier and laser printer manuals
(From: Gerald Chafee (GChafee@worldnet.att.net).)
Canon information
Canon has a faxback service at 1-800-526-4345. Quite a bit of technical
information is apparently available for their printers.
Epson printer switch settings
(From: Kim (103114.1526@compuserve.com).)
Some info can be found at:
Hewlett Packard information
HP actually has a fair amount of printer maintenance and troubleshooting
information on-line but no schematics:
Printer schematics?
"Working "on my own" Okidata microline 590. Need a print of mother PCB
and regulator PCB. A copy of the schematic will save time and let this
OLD TV tech enjoy life.... Thanks"
References
Here is the start of a list....
Stephen J, Bigelow
Wincrest/TAB Books, a division of McGraw-Hill, 1992
ISBN 0-8306-2563-2, ISBN 0-8306-3507-6 (paperback).
Bigelow et. al.
Windcrest Publishing
ISBN: 0070359768