asked Jun 5, 2009 at 11:56am
Canon Canon ImageClass D780

Canon Imageclass D780 paper jams w/new cartridge

I have this Canon Imageclass D780. I am prompted to replace the toner cartridge. I go out a spend about $155 for a new OEM Canon L50 toner cartridge.

I pull out the long strip, remove the old cartridge and replace it with he new one. Problem! I get an immediate paper jam right beneath where the cartridge seats. I remove the toner cartridge and the jammed sheet of paper. I try again. Same result over and over again.

I decide to try the old cartridge again and find it works fine, no paper jam problem. Try the new cartridge once again. Problem! Immediate paper jam. Back to the old cartridge, NO paper jam.

Can anyone offer a clue why the old toner cartridge does not produce the paper jam problem but the new one does?

Thanks so much.
Could be the drum shutter not properly attached. I've seen them come loose in new cartridges. Compare the 2 cartridges and look for differences, especially where the metal rods from the shutter go into the body of the cartridge.
by moe on Jun 5, 2009 at 2:57pm Add comment
Thanks, Moe. I will take a close look.

I actually took the Canon L50 OEM cartridge back to Office Max and got a refund. They didn't have any more so I got an Office Max version of the L50. That, unfortunately produced the same exact paper jam.

I called Canon Tech Support. The only suggestion they had is that I perhaps got two bad cartridges and I should try another. Maybe I will and maybe I won't. I'm pretty aggravated right now. This Imageclass D780 is probably about four years old but has I'm sure no more than 1,000 pages on its odometer. It's like brand new, but I may have to end up tossing it if I can't figure something out.

The paper jam is the same in all instances. When I remove the cartridge the page that jammed is visible right under where the cartridge seats. And in all instances there is about three inches of paper on the left side and two and a half on the right side. It looks like it was coming out at an angle when it jams. It's almost like the right side of the cartridge is pressing down on the little gate you have to lift to removed the jammed page.

I'm thinking that the thing to do is to have the original cartridge (the one that works) refilled somewhere if I can find a place that will do it.

The D780 is in my garage. I think I'll go out now and take another look at both cartridges as you suggested.

Thanks again for your help. It's always very much appreciated.

John - unknown
I've had cartridge caused problem many times in the past. When I can't spot the cause by looking at the problem one, I get the one that is causing the problem and do a side by side comparison. It's always worked for me in determining the cause. As for the Office Max clone, it's both expensive and inferior as are all the Office big box stores products. The company NuCote that supplies most of them, recently went into its second bankruptcy.
by moe on Jun 5, 2009 at 3:28pm Add comment
Thank you. I will be comparing the one that works with the one that doesn't tomorrow. I only bought the Office Max clone because they had no more OEM Canon cartridges.
by unknown on Jun 5, 2009 at 6:21pm Add comment
Sounds like the drum is not turning
remove the cartridge and with a black sharpie marker
place a dot on the end of the drum where it is not coated
you can pull back the shutter with the attached metal rod to access

replace the cartridge and test again-remove the cartridge to see if the dot moved position-if the dot did not move you probably have a drum drive engage related problem.

you can check the linkage by removing toner access lid connector with small pliers then lift this up and down with the lid open
to watch for drum drive ass'y to move in/out.

we have had good luck with eliteimage and allstate copymate
L-50 cartridges.
by Scytex on Jun 10, 2009 at 4:35pm Add comment
I am quite pleased to report that I have figured out the problem.
If you look inside the cavity where the toner cartridge is inserted you can see two black plastic shiny "tracks," one on either side of the cavity, left and right. The function of these tracks appears to be to guide the cartridge into the cavity.

I found that while the left track is stable and does not move, there was a little "play" in the right track such that with my finger I was able to move the track forward (away from me) and backward (towards me).

So I inserted the new Office Max L50 clone and once it was seated I grabbed it and pulled back. And it did move back towards me, maybe a quarter inch. I closed the lid, slid back the platen and tested my hypothesis.

Boy, was I happy to find that I no longer get the paper jam I described in my original post. I've printed tons of documents without a problem.

Now, if someone can tell me if the right track is supposed to have a bit of play in it my life will be complete.

Thanks so much to those of you who responded and offered your suggestions. They are very much appreciated.

by unknown on Jun 10, 2009 at 5:25pm Add comment
Have 3 of these in the shop
one has the rear guide broken at the top the other two
do move a little. all of them were copying just fine.

the rear guide is held in place with plastic tabs so I would expect
some movement...

sometimes the feed roll return spring will fall off causing no paper feed. and the paper feed clutch solenoid will stick.

the ribbon cable between the doc feeder and main pcb will
break causing communication faults.

and lastly there is the fuser but thats another post.
by Scytex on Jun 11, 2009 at 8:16am Add comment