A/C compressor relay not working

Tiny
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That is great. Thanks for the update. Do you mind giving us a couple sentences of what happened to get it working?

That info will surely help others in the future that read this. Either way, thanks for using 2CarPros and come back in the future. Thanks
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Tuesday, July 13th, 2021 AT 2:07 PM
Tiny
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It was the low pressure switch tested it and it was bad. Also the A/C wire harness pigtail was worn out changed that. I now have 34 degree air at the vents.
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Wednesday, July 14th, 2021 AT 4:58 AM
Tiny
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That is great info. Thanks for doing that. We really appreciate knowing what fixes things because others will benefit from it.

Thanks again for using 2CarPros.
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Wednesday, July 14th, 2021 AT 4:03 PM
Tiny
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No problem.
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Wednesday, July 14th, 2021 AT 4:04 PM
Tiny
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Found problem, shorted A/C wire.
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Friday, April 1st, 2022 AT 3:35 AM
Tiny
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Oh wow. That is great and thanks for coming back to update us as I am sure that info will help others in the future.

Thanks
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Saturday, April 2nd, 2022 AT 10:03 AM
Tiny
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Update: The A/C fuse keeps blowing. I put a test light on the ground wire on the plug going to the compressor and it lights so I have ground from PCM. When I check for power, I have no power. I jump the relay then I get power on A/C plug.

I’m going to ohm out compressor to see if clutch is bad. But could a bad low pressure switch cause fuse to trip or most likely the compressor is bad?
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Sunday, May 8th, 2022 AT 3:15 PM
Tiny
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Okay. Just to be sure, you are getting the A/C compressor fuse (shown in the diagram below) blowing?

If this is the fuse that is blowing then yes, it is the compressor. If you look at this circuit, then the compressor/relay is the only thing on it.

So, unless the relay is shorted to ground (unlikely) then the compressor is the only thing on the circuit that can cause this. Basically, what is happening is you have a path to ground prior to the load on this circuit which is the compressor. So that is the clutch as you stated is shorted.
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Sunday, May 8th, 2022 AT 6:36 PM
Tiny
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Yes, it’s the A/C fuse 10 amp that keeps blowing.
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Sunday, May 8th, 2022 AT 8:55 PM
Tiny
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I’ll update after I ohm out the compressor I I believe 2 to 5 ohms is a good compressor is that correct?
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Sunday, May 8th, 2022 AT 8:58 PM
Tiny
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This is going to vary based on temperature. But the coil of a compressor is normally around 3.5 ohms when in a shop that is around 75 degrees F. So, you are in the ballpark.
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Monday, May 9th, 2022 AT 4:36 AM
Tiny
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Hi, sorry to bring up an old thread but I'm having a similar issue on an 06 chevy Express 2500 4.8. Is the diagram you listed at the beginning the same for mine? I'm not getting ground on pin 85 of the relay and jumped the low pressure switch and nothing. I suspect the control head but I see there is a second pressure switch. So 1 where is the 2nd switch and 2 how do I test it. Thank you in advance.
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Saturday, December 17th, 2022 AT 12:55 PM
Tiny
KEN L
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No, the wiring diagrams are for a truck not the van can you please start a new question, and we will be happy to help you. Please post your new question here, you must be logged in.

https://www.2carpros.com/questions/new

Cheers, Ken
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Tuesday, December 20th, 2022 AT 10:39 AM

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