No Power to AC Compressor

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SpencerW

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High pressure cutout switch could also cause the issue. It breaks the same circuit that the low pressure switch closes when pressure gets too high. It is possible that it has failed. Installing a jumper in similar fashion to the low pressure switch would bypass it. Best thing to do would be to check for power at the hot terminal of the switches until you find your problem. Broken wire is also possible. You should have unswitched power at pin 30 of the relay, ground on pin 85, and your pressure switch circuit and control head will apply power to pin 86 when the AC is turned on. If all of those check out, it could be between pin 87 and the compressor clutch.

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I have a 97 LS swapped. Removed PCM and running TermX now. Trucks been done for 1.5 years, but never drive it because it's too hot for daughter. Trying to get the AC going. I'm having issues getting power to my compressor. I have no power going out the light green signal wire. Where does pin 30 go? Originally, I was running that to my compressor, but couldn't get power out of it either. I ended up purchasing an aftermarket setup and trying to integrate the factory AC button.
Thanks.
 

SAATR

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I have a 97 LS swapped. Removed PCM and running TermX now. Trucks been done for 1.5 years, but never drive it because it's too hot for daughter. Trying to get the AC going. I'm having issues getting power to my compressor. I have no power going out the light green signal wire. Where does pin 30 go? Originally, I was running that to my compressor, but couldn't get power out of it either. I ended up purchasing an aftermarket setup and trying to integrate the factory AC button.
Thanks.

This may help:

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You are referring to the light green wire in the picture? From the AC control head to the high pressure cutout switch? Or one of the other green wires in the compressor control circuit?
 

SpencerW

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This may help:

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You are referring to the light green wire in the picture? From the AC control head to the high pressure cutout switch? Or one of the other green wires in the compressor control circuit?
I think I have everything wired up. I ran the low pressure switch in line with my signal switch. I purchased a Holley AC kit. But the light green wire coming from my AC control head does not have any power.
 

SAATR

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I think I have everything wired up. I ran the low pressure switch in line with my signal switch. I purchased a Holley AC kit. But the light green wire coming from my AC control head does not have any power.

I think that wire may be a switched ground. Have you checked continuity between the LG wire and ground with the AC on and off?
 
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