HP Color LaserJet Pro MFP M177fw - ADF CLEAR

[mcilvadk]

I have an HP Color LaserJet Pro MFP M177fw printer.  I am having a problem with the ADF.  I can copy and fax from the glass, but the adf gives me a clear paper jam message.  I have to turn off the printer to reset the message.  There is no visible problem, and gear wheels move fine.  Printing works fine.

Posting here to see if there are any technical instructions for taking off the ADF, or any other troubleshooting techniques I could try.  

Thanks

[Valsimot]

If the ADF pickup rollers are rotating but not picking the paper then the first step would be to clean them with a lint-free cloth damped in hot water.
But if they rotate but shortly then you have a defective FFC cable connecting ADF electronics to the main board.

[mcilvadk]

The rollers roll if I move them manually.   They do not attempt to roll on their own at all. However, if I move them manually then work and pull the paper in without a problem.

Is the cable inside the small black box inside the larger black adf?  I do not think that part is sold separately.