LJ Pro M375dw paper jams 3/4 out of exit rollers

**Doug James** · 05-25-2017

The customer wants this beast fixed... The paper comes 3/4 out of exit rollers then jams. I replaced the sensors in the fuser. I am trying to reinstall the firmware but having trouble getting the printer drivers to install on my windows 10 laptop. I am down to trying the DC controller. This machine doesn't have much of a way to diagnose problems for sure. Thanks so much for any feedback !!

**Lance15** · 05-25-2017

I'd check the pickup roller. These rollers seem to wear quickly.

**Iowatech** · 05-26-2017

Is the fuser and its drive in good shape?

**Doug James** · 05-26-2017

Originally Posted by Iowatech

Is the fuser and its drive in good shape?

In great shape.. I don't see any problems there. the paper starts coming out of exit roller fine and the stops about 3/4 out and says jammed. When I pull the paper out it looks great.. Copier has 34K on it... real strange

**tonerjockey** · 06-02-2017

If this is like the color laser jet MFP M475, i have a customer with a bunch of them. and about a third of them starting about 80k, started jamming intermittently. they would do one page fine. some would do ten fine. whet would happen was at some point, while watching the pick up roller thru the small opening above the paper cassette drawer, i would notice that the slight deley from the time the trail edge passed under the pick up roller, there is a space ? about nearly an inch, then, "KACHUNK!", and the p.u. roller starts another cycle. well, when it would do thins jam, the trail edge, was just barely passing thre roller. so, when it jammed, there would be the trail edge of one sheet in the fuser, and the lead edge of the next, slightly overlapping the other by maybe 1/8th of an inch at the fuser roller. i tried here, and even Smarka i think, called LPT, P. works, De9o, and maybe another one. spoke to great lengths with those tech support departments. the only guy, i think Stuart ai P. works, ? said it had to be the paperr feed unit. he said a part breaks and i would notice it when i got it out. he assured me that even though it would take a first timer several hours at best to get it out, he has done it in 45 minutes. well, i took the heavy thing to the shop, spent the several hours getting it out. could see nothing broken. and the feeder was ? around 100.00, ? 69 to 120. i spent a while looking at the timing chart, and the sensors that would be culprits. i suspected it vould be that, of even the sensors on the fuser, or transport. it wasnt a fun job. i put it all back together and told the customer i didnt know what it was. when they had several , about 6 that had this same issue, i was going to swap parts but figutred it was futile.

this paper feeder if i remember it, i think the motor is off, then the motor and solenoid all start at the same time. strange. and i dont recal seeing the usual foam on the solenoid that gets sticky. i get bad feelings just writing about it. after they scrapped it again, i re took out that paper feeder, but just didnt feel strongly enough to try a new feeder. when they bought thse they were about 800.00 new. i think after a few years, the replacements were about half that, so repairing a problem like that, didnt make sence for them. but i would like to know if you find out.. Jim

**Doug James** · 06-02-2017

Originally Posted by tonerjockey

If this is like the color laser jet MFP M475, i have a customer with a bunch of them. and about a third of them starting about 80k, started jamming intermittently. they would do one page fine. some would do ten fine. whet would happen was at some point, while watching the pick up roller thru the small opening above the paper cassette drawer, i would notice that the slight deley from the time the trail edge passed under the pick up roller, there is a space ? about nearly an inch, then, "KACHUNK!", and the p.u. roller starts another cycle. well, when it would do thins jam, the trail edge, was just barely passing thre roller. so, when it jammed, there would be the trail edge of one sheet in the fuser, and the lead edge of the next, slightly overlapping the other by maybe 1/8th of an inch at the fuser roller. i tried here, and even Smarka i think, called LPT, P. works, De9o, and maybe another one. spoke to great lengths with those tech support departments. the only guy, i think Stuart ai P. works, ? said it had to be the paperr feed unit. he said a part breaks and i would notice it when i got it out. he assured me that even though it would take a first timer several hours at best to get it out, he has done it in 45 minutes. well, i took the heavy thing to the shop, spent the several hours getting it out. could see nothing broken. and the feeder was ? around 100.00, ? 69 to 120. i spent a while looking at the timing chart, and the sensors that would be culprits. i suspected it vould be that, of even the sensors on the fuser, or transport. it wasnt a fun job. i put it all back together and told the customer i didnt know what it was. when they had several , about 6 that had this same issue, i was going to swap parts but figutred it was futile.

this paper feeder if i remember it, i think the motor is off, then the motor and solenoid all start at the same time. strange. and i dont recal seeing the usual foam on the solenoid that gets sticky. i get bad feelings just writing about it. after they scrapped it again, i re took out that paper feeder, but just didnt feel strongly enough to try a new feeder. when they bought thse they were about 800.00 new. i think after a few years, the replacements were about half that, so repairing a problem like that, didnt make sence for them. but i would like to know if you find out.. Jim

Thanks so much for your feedback !!! I will let you know. My customer is in the same boat. They bought this for about a grand several years ago and want to fix it. The paper here jams every time. Just when the trail edge of the paper is entering the fuser. The paper is about 3/4 of the way past the exit rollers. I changed the sensors in the fuser with known good ones. I am waiting on a controller board and I will let you know...

**theengel** · 06-02-2017

I've had a few problems with this machine that I just couldn't figure out. When I started going over prices for the most likely parts, customers always dropped it and got a new machine. But these are decent machines when they work.

In your case, I can't remember what kind of feed solenoid is on there. I would suspect that or the fuser itself.

Check the error history to see exactly which sensor is claiming to have a problem.

**Lance15** · 06-02-2017

Maybe a very long shot, but, is the firmware current? "Current" on HP is 2015. I've come across a few stupid issues like this and I try firmware and it seems to correct things.......sometimes.

**Doug James** · 06-02-2017

Originally Posted by Lance15

Maybe a very long shot, but, is the firmware current? "Current" on HP is 2015. I've come across a few stupid issues like this and I try firmware and it seems to correct things.......sometimes.

I tried to reload firmware and couldn't get the drivers to load and gave up. That's my next step...

**tonerjockey** · 06-02-2017

i am trying to use the "attachment" icon to post the timing chart and paper feed diagram. it wont load. if you know how to do it let me know. or i can email you the pictures from the s.m.
p. roller can also email you the file. the manual shows the M375 and M475 on the same book. paper feeder is part # RM1-8045-000. the only parts spared off that are the p.u. roller, sep roller and clip. p. roller price shown on website is $110.95.