1985 GMC Compressor Wiring

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cattleman05

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Braeden
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1985
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1500
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350
I recently bought a truck with a/c but it doesn't work. I noticed that there is no plug connected to the 2 prongs on compressor and I don't see any wires hanging anywhere that would go there. Could anyone tell me where/what the plug and wires should be coming from?? TIA
 

75gmck25

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IIRC, the stock A/C plug is a flat two wire connector, but one wire is just a short ground wire that runs over to the compressor bracket. You only need one wire to activate the compressor. I would check A/C supply houses for the GM connector, since its a common item. However, you may be able to also use a standard insulated spade terminal connector.

Bruce
 

Charlie

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:welcome:
 

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Those two wires (12v, Grd) energizes the coil activating the magnet that engages
the clutch on the compressor.
Easy peasy.
 

1987 GMC Jimmy

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The wires should be there somewhere. Worst case scenario you have to run the wire from the HVAC controller. I will say that there’s also a diode right there at the connector, but I can’t remember what they put it there for.
 

Craig 85

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It should be a green wire similar in shade to this if you find it.

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73c20jim

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Check the wiring diagram for the ac. The green wire goes to two other connect plugs that control the dis/engagement of the compressor pulley.

It's got to get a "go" signal from both to operate the compressor.

Wiring diagram for ac is very simple.
 

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