i looking for a downloadable diagram of the wiring fo my 92 cummins truck.my pcm died and im trying to bypass it to "normal".i bypassed the alt reg[easy] and manually controlled grids, im wanting to get the a/c working manually.i assume the pcm controls the a/c because the cluth engages in and out w/ the ck eng lite.i was wondering if the pcm controls the cycle of a/c? i looking for a manual,but my buddie that has one,isnt my bud any more. lol.untill then does anyone have any pic ect of the 92?thanks,great site!!!!

 

Check the crank sensor wiring.

The PCM controls the A/C clutch.

 

Sent you a private message. I have the wiring diagram, can't upload it for some reason

 

There is a relay on the Drivers side fender. there should be a blue w/black tracer wire, blue, and blue w/orange tracer. Short the blue w/orange tracer wire to ground and the compressor should kick in.
The signal for the PCM to turn the A/C system comes from the heater control, grounding the other side of the Blue/orange wire.
So, all that being said. Look at the firewall bulk head conector, in the lower left corner of the connector the BL/org wire should pass thru there, pull that wire from the harness ( bulkhead to PCM) connect the PCM end to the same location on the relay. that should do it. Clear as mud????
PM me if you have further Q's
Bill