LaserJet 5si Duplexer Error 13.8

Hi everyone,

I've just installed a duplexer in my 5si, and it simply will not work. It seems that the paper jams as it reaches the turnaround area behind tray 3. Every time it prints double-sided, the paper just stops there. It doesn't seem to be jammed, as it's relatively loose.

Also, I have two different fusers (someone had suggested it could be a fuser issue) but it doesn't work with either of them.

I always get the 13.8 Paper Jam error, which tells me the jam is in the turnaround area, but of course I already know that.

All the rollers involved seem to be fine (I opened up the duplexer to check its rollers too).

Do I just have a bum duplexer, or is something else wrong?

Cheers,

Aziraphale

Is the duplexer built for a 5si or an 8000 printer?
Check under tray 3 for any paper or blockage, this could cause jams.