[Jamming] HP LJ Pro M476

[aAandy]

ITB stops momentarily when paper reaches transfer roller, resulting in a z-fold jam - as a temp measure i cut down the transfer roller springs to reduce pressure

would like to return with a permanent fix - anyone seen this before?

thanks in advance

[aAandy]

Re: HP LJ Pro M476

bump

anyone? anything?

[GIUBOSS]

Re: HP LJ Pro M476

have you checked all the flag sensors if they return correctly? how many prints does it have, transfer condition and fusers?

[aAandy]

Re: HP LJ Pro M476

have you checked all the flag sensors if they return correctly? how many prints does it have, transfer condition and fusers?

110k, paper sensor flags all operate normally, transfer & fuser look fine - ITB stops just for a moment when paper reaches registration, then jams with a 1 inch Z fold at the top - reducing the transfer roller pressure by cutting down the springs got it to work but this is only a temporary solution

during warm-up with the back door cheated i could not stop the ITB with my finger

[GIUBOSS]

Re: HP LJ Pro M476

condition of the paper pick-up rollers?

[aAandy]

Re: HP LJ Pro M476

condition of the paper pick-up rollers?

new - curious to know what you think a feed roller may have to do with the ITB stopping when paper reaches registration?

[GIUBOSS]

Re: HP LJ Pro M476

usually I do not neglect any details for jamming problems, a delay or advance on the paper detachment could compromise the time on the way to the register. The register magnetic clutch to be checked

[aAandy]

Re: HP LJ Pro M476

usually I do not neglect any details for jamming problems, a delay or advance on the paper detachment could compromise the time on the way to the register. The register magnetic clutch to be checked

after 34 years of printer repairs, neither do i as these are the first things any tech checks before consulting other techs

thank you kindly for your responses, but i am looking for responses from people who have seen this specific problem before and have successfully applied a solution

i agree the ITB drive clutch is the likely culprit as reducing the transfer roller pressure remedied the problem and got the machine working, however i couldn't stop the ITB during warm-up with my finger

[GIUBOSS]

Re: HP LJ Pro M476

I would try to invert the two main motors if you have time ..

[tech28]

Re: HP LJ Pro M476

Paper size? By pass doing same thing? Have seen that problem before a few moons ago, sorry have to see if I have a solution in my files. Ill get back, not much work coming in.

[spree]

Re: HP LJ Pro M476

Hello. Problem with HP color LJ Pro M476: paper jam in tray 3. But the printer has only tray 1 (manual) and tray 2. Error log (13.000 - paper jam). Sometimes continue printing 30 pages and after that "paper jam in tray 3.". Than turn OFF/ON and immediately "paper jam in tray 3". Try to replace pick-up in tray 2 :-), try to upgrade FW, try to print from tray 1, from tray 2, try to make copies (without sending jobs from PC) and still the same... Any ideas? Formater (maybe)?