Hello a204600, I don't know if the codes are the same on your '92, but here is
something that I found for a '95:
These codes were taken from the '95 XJ/YJ
12* Direct battery input to PCM was disconnected within the last 50 key-on cycles.
33* An open or shorted condition detected in the A/C clutch relay circuit.
15** No vehicle distance (speed) sensor signal detected during road load conditions.
55* Completion of diagnostic trouble code display on the malfunction indicator lamp (check engine lamp).
I hope this helps.
'94 YJ 2.5L/5sp - White Jeep Club #55