asked Mar 10, 2006 at 10:54pm
Hp HP LaserJet 4M

HP4M (not Plus) Paper Jam after startup self test

My employer was getting rid of a bunch of old equipment, and I managed to snag an HP4M... It had been sitting around unused for quite some time, but I was told it worked.

Upon getting it home, I plugged it in and fired it up. When I fired it up, the fan starts spinning, and the 05 Self Test Displays on the screen. Nothing else moves (rollers or otherwise). After a few seconds, I get a 13 Paper Jam error.

I check the paper path, and don't see any paper, open and close all the doors, and reset the toner cartridge. No change.

I found a manual online, and went thru it's test proceedure for testing PS1 - I started the printer with the lid open and the cartridge out. I then taped PS1 down (Or I think that's what it is. - facing the printer it's on the left side, theres a swinging door with a slot that goes over it). I then closed the door. - I got the same error message - Paper jam. The docs say the PS1 is bad. Is this a common failure? Or should I be looking for something else? The printer has 110800 pages that have been run thru it (according the service menu). If the PS1 is the problem how much is the part?

Any ideas would be great.

hi open the rear door and look at the fuser assembly, there is a flap on the fuser for you to drop down, then you will see a flag
opperate the flag with your fingers, with doing this follow the route of the flag and make sure it is not locked in a open position any were, also check flag has no side movmend only back and forwards.
also remove toner cart and lift metal flap to see any paper in path, you can also remove paper tray and look up into paper path......shotgun
by shotgun on Mar 11, 2006 at 1:24am Add comment
I moved the flap on the fuser, the flag I'm looking for is about 2 inches in on the right hand side right? It moves, but is notchy.. Which position is the one indicating no paper? Down I would guess.

I lifted the flap, and no paper there, there is no paper in paperpath from the paper tray.

by rhein on Mar 11, 2006 at 7:35am Add comment
Ok, I finally found where that spring is. One question I have is, doesn't the spring go OVER the arm piece? It looks like there is a guide for it, and when it does, the spring is in a straing line. When it's under the arm, it's not a straight line (however it isn't stretched).

In any case, it didn't change the error message.

by rhein on Mar 11, 2006 at 8:33am Add comment
Make sure the interlock for the back door is working right. It pushes in the black post on the right when looking from the rear. It that switch is not engaged you get a jam error because the printer thinks the back door is open.
by dmzcompute on Mar 11, 2006 at 9:02am Add comment
Have a picture of that? I think that the switch is moving.

Why couldn't they have included some logic that said "Paper Jam at Switch x" to make life easier?!?!?

by rhein on Mar 11, 2006 at 9:33am Add comment
The sensor on top with the spring on it is the same sensor for the door and the fuser exit. The door has to be closed and the fuser exit arm in the relaxed position to satisfy the interlock. You can manually activate the sensor on top by making sure the flag is blocking the optical sensor below the spring. You will also have to hold down the door interlock switch at the front of the printer. If the printer display goes to ready, then you have some kind of problem in the interlock between the fuser, the door and the sensor mechanisms. That's pretty much the only thing that will give you a paper jam message on startup.
by moe on Mar 11, 2006 at 11:30am Add comment