Air conditioning not working?

David Wilhite · 2020-06-05T14:57:45+00:00

Compressor quit, replaced compressor, dryer, clutch cycling switch (low pressure) and manifold hoses on compressor. Pulled vacuum, no leaks,jumped compressor at relay and added Freon. Now compressor will not come on even by jumping. Replaced PCM, still no power. What should I try next? David.

1999 GMC SIERRA

195,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC

KLSHIEL

CAR REPAIR CONTRIBUTOR
163 POSTS

I believe your system is R-12 to be sure look at the fittings in the system. R-12 fittings are small and treaded like bike tire air fittings. R-134a fittings are short stubby quick disconnect fittings. Only a qualified shop can do anything if it is a low R-12 problem. Something other than how full it is can cause your trouble. with motor running look at the AC compresser. if the clutch is engaging suspect low pressure or a clog in system.

Jan 11, 2021 at 9:29 AM (Merged)

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