HP 82162A printer HP-IL Transmit Err

[MeindertKuipers]

Summarizing, you get the TRAMSIT ERR whenever the printer is in the HI-IL loop. Most likely this is an indication that the physical loop is somehow disturbed.
First test would be to check the electrical continuity of the IL loop and cables at the printer side with an Ohm meter, and if that is rougly the same as for the cassette drive. If that checks out good do the same for the loop's pulse transformer block of the printer (part identified with 9100-4226). This part is described in a document 82166-90020 HPILkitTech. Verify continuity of all transformer coils and connections.
If that checks out verify if all components between the pulse transformer and the HP-IL IC are functioning correctly.
I once had an issue with one of the transformer wires broken (of another HP-IL device) at the soldering joint, and resoldering solved the issue.

Good luck!