Two issues with Canon s750

[Trigger 37]

drfugawe,... This is a good lesson for a lot of people. The problem with this printer from the beginning was that the purge unit was so gummed up with dried ink that is was stuck in some position,...probabaly fully extended. All that drfugawe did was to manually cycle the purge unit through one full cycle which broke the gummed up seal. I'm telling him now he should have done more since this problem will come again.

While he had access to the purge unit, he could have cleaned all of the excess ink off of all parts. Going a little further, once he had the covers off, he could have take the base chassis out of the bottom case and removed the entire purge unit and cleaned all parts of it. He could have also removed he waste ink pads and cleaned them, and then reset the waste ink counter in the eeprom data. Of course, since he now knows how to get at all of these things, he can do when he has the time. This will keep his printer is good condition for a long time.

Some people are amazed how such a very small thing like gummed up dried ink could cause such a problem,... but it happens everyday and most people never get it fixed,... they just through the printer away.

If any of you see a similar problem with your printer. you can use some windex or hot water to clean off the purge unit wiping blades and as much as possible of the purge pads without ever taking the printer apart. I've even gone to the extreme by spraying a very small stream of windex through a small straw onto all the purge unit parts, just to remove the gummed up ink.

drfugawe,... Thanks again for bringing this problem to this forum and showing how it can be resolved.

 

[drfugawe]

All thanks due to you my friend - and I'll get that baby in top operational shape just as soon as I can do the necessary research here to do it well.
john

 

[drfugawe]

Hey Trigger!
Sorry to say that it's me again - so soon! The printer did fine for the better part of two days, and it again parked the carrage on the right, and refused to print - So heeding your message, I broke it down again and cleaned it out as best I could - I stopped short of pulling the internals out of the chasis (to get at the ink pad) mostly because I couldn't find anything on how one pulls the innards out of there. But I did probe around the base of the inside with sev Q-tips, and I couldn't locate any wet ink, so I'm assuming that means there's not much down there. But I did clean up all parts I could get to easily, and I took the printhead out and cleaned it up. Put everything back, closed it up, and ran the waste ink counter reset code. It immediately told me that I needed to run the printhead alignment, so I did that, then I also did a nozzle check printout - all looked good. After all that I went to print a doc, and it went back to parking the carrage on the right (wouldn't even come to the middle when top was raised) and it's not going through the initial "prep cycle" which I think is mandatory when it is first turned on - right? It's also giving me the blinking light code, 4 alternating orange with 4 green blinks, followed by a long green. Everything I read says that's the code for "full waste ink tank" - so I ran the reset code for that again - still nothing!

Sorry to be back so soon with bad news - any other ideas? Seems strange to me that I can print during the diagnostic/maintenance phases, but not anything else.

Thanks Trigger,
john

 

[Trigger 37]

drfugawe,.. Sorry to hear your problem has returned. The 4 blinking alternate Ornage/Green lights have nothing to do with the Waste Ink error for this printer. I don't know where you got that data but it is wrong. $ blinking lights is a "Purge Unit Error". This is telling you that something is still wrong with the purge unit. It may not be grinding anymore, but there is a photo sensor in the back bottom of the purge unit which watches the complete cycle of the unit and informs the logic board that all is ok. This sensor is now telling the logic board that something is wrong with the cycle. It only course to to take the printer apart and take out the purge unit and examine it very close.

You never did tell me what you did to get it to work before. I assume that you followed my instructions and cycled the purge unit manually through one cycle,... then it worked. Now the printer has gone back into the "Brokent" mode and it is clearly the Purge unit. You're going to have to get the purge unit out and see what the problem is. If it is broken and you can't fix it, you can buy one from Canon for about $25.

I still have a little more work to do to finish my Repair Manual for the S750 printer. When it is done I will let you know and it will be listed on eBay.

 

[drfugawe]

Hi Trigger,
Thanks for responding - in my message #10, I tried to outline what I had done in the process of following your instructions - I guess I may be over-sensitive to filling the page with "verbage" for the sake of filling the page - perhaps a carryover from a past life. In any case, Yes, I tried to follow your good instructions and apparently, they at least temporarily solved the problem - today, I'll get busy with pulling the purge unit out and inspecting it carefully - and while out, I'll of course clean it as best I can.

Question- How interchangable are the internals, specifically here, the purge unit, with other Canon printers? And how would I go about finding out this kind of info? The reason I ask is that I'd like to keep this unit working as long as possible, since it uses one of the least expensive carts out there, and it's not a bad printer besides. Another reason I ask is that I'm a Thrift store junkie, and I frequent one shop where they specialize in computers, etc. They always have many printers for resale, but I noticed that they all were in working order. So I asked the clerk what they did with the units that didn't work? She said, "we just plug them in and if they don't work satisfactorily, we junk them." Since I've learned here that many printers are thrown out because of the waste ink issue, I asked her specificially if they tried to reset any printers that had that message, and she responded that "no, they didn't spend any time fooling with them like that, if they didn't work, they junked them! So I suspect that this shop may be the source of lots of parts, if in fact the parts are interchangable.

What do you think? I'm also toying with the idea of learning a little bit about how these things work, and maybe finding a worthwhile activity that'll keep me out of trouble in my retirement (which I'm enjoying just as you are!). And, yes, I'd love to know when your repair manual is done.

Thanks for your willingness to keep this dialogue going, Trigger - it's much appreciated.
john

 

[Trigger 37]

drfugawe,... The purge unit in almost all of the i Series printers is 98% the same. Some have a little different mounted screw holes but the working guts are all the same parts.

What kind of thrift store are you talking about and what major city is it near. I'm in Northern California and we don't have many here.

 

[drfugawe]

Hey Trigger,
Just finished a two day complete cleaning job on my ailing printer - needless to say, I learned a lot. I'd like to tell you that upon plugging it back in that it was like new, but sadly, the purge unit problem persists (it makes a nasty noise upon startup, and nothing moves beyond that - same alternating green/orange blinks (4) sounds as if the purge unit were frozen). So I guess I'll keep my eyes open for a replacement purge unit. BTW, my printer is an S750, not an i series - is it also true that the S series used the same purge unit throughout?

Your question about the local thrift stores hereabouts (SW Oregon coast) made me laugh - these are only small stores - not an urban area here - but there is one place (Bay Area Enterprises, Coos Bay - amazing how many "Bay Areas" there are in the US!) that specializes in reselling old appliances and computers, and they must get lots, 'cause their store is always crammed full. But, as I said, they apparently pitch all non-working units, regardless of problem, and therefore may be a gold mine of printers with minor issues!

I took some pretty good notes while breaking down and putting the purge unit back together (because if I didn't, it wouldn't have gone back together!). Do you think it would be worthwhile if I put those notes together in the form of outlined instructions on how to work with the purge unit? I noticed as I was doing my research this past week that there are lots of intructions for getting to the waste ink pads and cleaning it, but not much on breaking down and cleaning the purge unit (I mean detailed instructions for clutzes like me). I also remember coming across a comment of yours which said that sometimes you forget that most of the readers of this forum have not been working on printers for the last 20+ years, and that sometimes your instructions are aimed toward the more experienced forum readers. From my recent readings I can tell you that 7/8's of this forum's readers have NEVER been inside their printers! Whatever.

Thanks Trigger - I've had fun this week - but I sure would like to be able to say one of these days, that I got this baby working again.
john

 

[Trigger 37]

drfugawe,... The S Series of printers use the same insides as the eary i Series, and all of the use the same basic purge unit. One great thing about Canon is that when the come up with a good design, they use it in all of their printers. I'm sure you took good notes in the disassembly of the purge unit,... but did you also take Digital pictures. My Repair Manuals include the pictures and the words on how to take apart and repair the detailed parts.

If you have one or more pictures of the insides of the purge unit as you took it apart, they would help me to see what is wrong with it. If it is still grinding, it sounds like it is slipping gears, or some gear has come out of mesh with some other great. Once I had a printer where someone had tried to force the printhead away from the home position even though it was locked in position by the white "Tongue" of the purge unit. In trying to force the carriage away, they "Fractured" the black plastic housing of the purge unit, and this allow one gear to dis-engage and all it could do was grind against the adjacent gear. I took that unit all the way down to the smallest part. Then I put epoxy on the fractured housing and let it dry. When I put it all back together, it worked perfectly. If you can't see what is wrong, you won't be able to fix it. If it is broken you will have to find a new one or a used one to replace it. If you had the pictures I know I could help. However, if something inside is broken, like a gear, you can get parts and you need a replacement unit.

Go to your thrift stores and try and find any of the S Series or i Series printers. If you can get one cheap, that may be you solution. Before you spend money on it ,... Call Canon Parts Department and ask them how much is a Purge unit for the S750.

 

[arizonan]

Trigger 37's instructions on 4/27/08 worked perfectly for me today. I had a loud noise at startup followed by 4 orange lights and 1 green. When I opened the cover, the printhead wasn't locked and there was a significant amount of ink and dust around the purge mechanisms. I cleaned off the ink and dust, pushed down the locking bar and slid the printhead over to relock it, and then slowly moved the gear as suggested. The lock went down and released the head. I slid the head out of the way and let the purge process go thru a full cycle. I didn't see any broken parts. I powered it on and it works great. No noise or orange lights. Thank you.