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Old 07-17-2015, 09:31 AM
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brcidd brcidd is offline
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Re: AC Compressor only works when jumped.

With a/c commanded on- gently pull the a/c relay in and out- does it click each pull? If so, problem is between relay socket and compressor, or bad relay (swap it with horn relay).

If not, then problem is that computer is not allowing compressor to come on from a bad input or sensor. The pressure sensor you replaced should have been the 3 wire pressure transducer- were all three wires good? one is ground, one is 5 volt, one is reference voltage corresponding to refrigerant pressure- use your volt meter with sensor plugged in to monitor.

A Tech II scan tool would really help- other things like a bad engine temp sensor reading really hot will not allow compressor to engage- does your car have other issues?
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