A/C clutch will not engage?

2000 CHEVROLET SUBURBAN
300,000 MILES • 5.2L • V8 • 4WD • AUTOMATIC
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VBOTICS
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A/C compressor locked up, burnt off belt. Replaced A/C compressor, belt, pulley, high and low pressure switches, actuators on interior cab. Jump pins on relay and ac clutch activates. Also replaced interior HVAC control panel. Out of options other than tracing blue wire from relay to control panel. Seems like the relay just isn't getting the signal to turn on. Also, when manually trigging compressor the low sideline seems to frost up, but never blows cold inside cabin.
Sep 2, 2024 at 3:07 AM
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STRAILER
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Does the compressor run if you jump the low-pressure switch? The blk and drk grn wires? Here is the location of the pressure sensor and the wiring diagrams for the compressor circuit so you can see how it works. Please go over this guide as well:

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.
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Sep 2, 2024 at 11:53 AM
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VBOTICS
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Negative, no change when jumping low pressure switch.
Sep 6, 2024 at 9:31 PM
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VBOTICS
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The low side is at 35 psi and the high is at 225 psi when I jump the relay.
Sep 6, 2024 at 9:32 PM
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STRAILER
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Can you please check the IGN1 fuse for power and make sure the fuse has power?

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Also, did you swap out the AC relay? Also, there are high pressure switches on the back of the AC compressor that can be jumped which if the compressor comes on the high pressure switch needs to be replaced. Check out the images (below). Let us know how it goes


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Sep 7, 2024 at 7:27 AM
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VBOTICS
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I swapped out the relay with the horn relay that I know works, no change. I will double check the fuse.
Sep 7, 2024 at 10:54 PM
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STRAILER
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Yep, see if there is power at the fuse as well.
Sep 8, 2024 at 11:13 AM
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Omg, the fuse was fine, bypassed the high pressure switch and it works! Problem found! Hooray! Thank you sooo much, I figured a view from outside would help.
Sep 8, 2024 at 3:30 PM
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STRAILER
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Glad you could get it fixed, thanks for letting us know. Please use 2CarPros anytime we are here to help.
Sep 9, 2024 at 8:06 AM