What is this connector? - SOLVED

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joems

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Need help please.
1983 GMC pickup factory AC. The truck came without an engine/tranny. It does have (most?) everything else at the firewall.
I've added the factory condenser, accumulator and replaced the evaporator. I've made all the AC lines.
It has the stock fan motor, motor resistor and relay.

What is this connector? It is OEM. It is in series with the 12v line that loops through the low pressure switch. It is not the compressor clutch connector (wrong location and wrong connector).
I'm guessing it's some sort of AC cycle switch but if it is, I'm missing that switch and don't know where it would mount.
Any help would be greatly appreciated. I feel I've searched the entire internet, twice :(
Joe

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squaredeal91

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I'll try to look at our 85 soon for you and see what I find
 

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I think you are correct, Joe. I have an '83 GMC also, but mine was converted in the past from a 3 wire like yours to a 2 wire compressor.
It also has a toggle switch on the dash to cut the compressor on.
Always something to fix, right?
 

squaredeal91

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I believe this is it. Goes or comes to that round one below column. By exhaust.
 

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joems

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I think you are correct, Joe. I have an '83 GMC also, but mine was converted in the past from a 3 wire like yours to a 2 wire compressor.
It also has a toggle switch on the dash to cut the compressor on.
Always something to fix, right?
Mine is going to a 5.3 LS, so 2 wire clutch with the High pressure switch in the rear of the compressor. I have it all figured out except the cycling control and what is the connector for...
 

joems

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I believe this is it. Goes or comes to that round one below column. By exhaust.
That looks like the right connector, but I don't have the pigtail with the round end. Can you tell what the round end eventually hooks to?
Thank you.
 

squaredeal91

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That looks like the right connector, but I don't have the pigtail with the round end. Can you tell what the round end eventually hooks to?
Thank you.
I'll look when I get home
 

Turbo4whl

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Some GM's had a normally closed pressure switch on the power steering pump. Since the engines were so leaned out, when you turned the steering wheel to the lock with the AC on and pressure build in the pump, engines stalled. So they had the switch to cut off the AC to keep the engine from stalling.
 

squaredeal91

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It goes into the wire loomed harness that goes along frame above fuel tank to tail lights. I'm guessing it goes the other way tho.
 

joems

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It goes into the wire loomed harness that goes along frame above fuel tank to tail lights. I'm guessing it goes the other way tho.
Yes. I'm guessing it goes into the cab.
 

squaredeal91

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Do you have a multi meter? Use the ohms to help trace the wires inside and use a jumper wire to make your leads long enough to check continuity. I wonder if the wires are in there but just cut.
 

Turbo4whl

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Okay, instead of the type of wiring that turns the AC compressor off, how about bumping up the engine idle when the AC is on.

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joems

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Thanks to everyone who responded. I found an original (complete) example. That connector plugs into a 'pigtail' that leads to the throttle (idle-bump) solenoid and then onto the compressor clutch.
 

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