Ac compressor will not come on?

1996 CHEVROLET TAHOE
V8 • 4WD • AUTOMATIC
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STACIE5606
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  • 1 POST
ac compressor will not come on unless we jump it from the compressor to the battery. We have replaced cycle switches, control unit in the dash, all lines, accumulator, condenser and orifice tube and relay and checked all fuses.
Apr 13, 2011 at 5:37 AM
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SQM
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Hello,

It sounds like you have a wiring issue for the compressor. As you are able to jump the compressor from the battery, it seems that the compressor is not getting power.
First check to see if there is voltage to the harness that plugs into the compressor.
If there is no power you will have to trace the wiring, as there is likely a short in the circuit.

Here is a helpful guide of testing wires:

https://www.2carpros.com/articles/how-to-check-wiring

I attached the wiring schematics below.

Please let me know of any questions.
Thank you.
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Sep 26, 2021 at 9:43 PM