asked Dec 2, 2002 at 5:20pm
Hp HP LaserJet 4M

laserjet 4m paper jam

I'm having a problem with a paper jam on my hp laserjet 4m. The paper gets stuck about 1 inch out of the fuser. If I pull the toner out, then the fuser, the paper stays in the fuser and I can manually get the paper out by turning the gear. Nothing seems stuck and all gears appear to be in good condition. Is there some sensor back there telling the printer to stop advancing the paper.


There is an exit sensor arm on the fuser. The pivot pin breaks off and the arm will flop around. You can move the arm with your fingers. It should move smoothly up and down without side to side wobble. We have the guide plate assy. you need in stock and a video that details fuser disassembly.
by moe on Dec 2, 2002 at 6:11pm Add comment
Thanks for the reply. I took apart the fuser assembly, but don't see anything broken on the pivoting flag. I also tried another fuser assembly with the same result. Could the sensor in the printer have gone bad? Is this replaceable.

by MikeF on Dec 3, 2002 at 10:31am Add comment
Can you tell us which part of the machine these printers look I send you a copy of the service manual for ya if Moe would let me too.

by Stuart on Dec 3, 2002 at 12:42pm Add comment
The real optical sensor is up on top. The sensor flag on the fuser works a linkage that goes up there. The point where it's stopping is about the time that the DC controller is expecting to see the paper hit that sensor. Not seeing the return, it assumes the paper jammed in the printer. We have a photo of the optical exit sensor in our troubleshooting section. You could take the top off and watch the arm movement in and out of the sensor. It couldn't hurt to blow some air through it. Doesn't take much dust to block the photocell.
by moe on Dec 3, 2002 at 6:11pm Add comment