Paper jam or no paper on a C1660W

Hi,

I'm stuck with an error code 024-969. The machine starts fine, rolls the exit rollers, but trigger the error whenever I try to print (e.g. printer settings, straight from the printer).

I tried resetting the printer in various ways.

I went to the diagnostics mode and DI-2,4,5, and 7 return a "L 1", the others return a "H 0".

Can you confirm which sensors are the issue and where they're located?

There is an old topic with links to the diagrams and references but the links are dead.

When I try DO tests, nothing happens except for the fan.

Thanks in advance.