92 2.3 AC problems

[roadracer61]

I just bought this truck for work, so I honestly don't know much about it. When I went to look at it before I bought it, the AC worked fine. I had to put a radiator in it, then drove it home. After I got home, the AC stopped working. Light on the control panel comes on, but nothing beyond that.

Started my investigation, which was limited because I don't know a lot about AC. I found that there is power coming from behind the control panel when the AC switch is pressed. The fuse under the dash is good. The relay by the fire wall has power going to 2 legs, not the other 2, but if I ground one of the legs, the compressor kicks on and it blows cold air, although it does not cycle.

The low pressure switch has no power on either side, and there's an odd looking thing that sets back behind the relay that has no power on either side as well. (kinda looks like a piece out of an old radio with a copper coil wrapped around the bottom and 2 leads off the top)

Does anybody have a schematic for this AC system? I'm thinking it's a wiring issue SOMEWHERE, but I have no clue where to look.

 

[Earl43P]

I'm looking at a 93's schematic.

Here's how power routes:

Fuse #17 (10A) to AC Panel (W/LB wire)
Switch closes, power comes out on P (Pink?) wire goes to PCM Pin 43 and (splice) to AC Cycling Switch.

Out of Cycling Switch on the DG/O wire to PCM Pin 10 and (splice) WOT (wide open throttle) relay contacts (which remain closed unless throttle is floored).

Out of WOT relay on the BK/Y wire to (splice) Clutch Coil and Clutch Diode.



The PCM Power relay (contacts) route power to the WOT Cutout relay on the Red wire. Its ground comes from the PCM Pin 54 on the PK/Y wire. Grounding the PK/Y wire with the key in Run will OPEN the WOT relay contacts and disconnect the power to the clutch coil.


If you'd like a copy of that schematic, send me a Private Message with an E-mail address.

Just click on my username to send a PM.

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