PCM AC problem?
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Joined: Mar 2010
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PCM AC problem? I have a 01 Z28 and my ac will not automatically come on. I can run a hot wire to the wire that goes to the ac compressor and my compressor will kick on and the air is freezing cold! But thats the only way i can get my air to work. I changed my high pressure switch on the ac line but that didnt fix it. The only thing left is the PCM right? It controlls the power to the compressor right? When to kick on and to turn off? 
HVAC fuse #6 feeds power through the heater control panel to the pcm on pin #17 C1 when a/c is selected. Then the pcm will close the compressor clutch relay if the pressure is correct. The relay gets its power from A/C Cruise fuse underhood. Check the fuses and relay if you already haven't.
I have had A/C fail at idle because of some "unstable idle"
deal, after the cam swap. Too much surging and it will
not engage.
Also had a problem when I cut the wrong purple wire,
trying to relocate IAT, two of 'em close together on
one of the PCM connectors.
If A/C runs with the RPMs held up out of idle, maybe
it's the "unstable" problem.
deal, after the cam swap. Too much surging and it will
not engage.
Also had a problem when I cut the wrong purple wire,
trying to relocate IAT, two of 'em close together on
one of the PCM connectors.
If A/C runs with the RPMs held up out of idle, maybe
it's the "unstable" problem.
