Hp Lj 4200 13.20.00

[Brian]

I have recently seen two HP LJ 4200's that have the following problem:

As soon as the printer has initialized the screen reads:
13.20.00 Jam in top cover area.
After opening and closing the top cover the screen reads:
13.20.00 Jam in rear door.
There is no paper jammed or any other obstruction in the paper path.

In both cases HP fixed the printer as in was still under guarantee, but I would like to know what solution is to this problem.

Thanks for any info.

[MichaelTech]

This means that there was paper at one of several sensors at start-up.
I could be a faulty sensor\flag, or if dirty, a little slow in its motion.
Aleays check the paper tray, to see if it pulls up a page only part way. It will trip the paper feed roller assy. flag, and give that error.

[Brian]

No paper anywhere, the error moves from one place to another just by opening the cover so there must be something else wrong with it.

[zydeco]

I have seen this, usually a spring came off of one of the sensors in the transfer assy.