1995 Pontiac Firebird A/C clutch not engaging!

VISION777

MEMBER
1995 PONTIAC FIREBIRD

Air Conditioning problem
1995 Pontiac Firebird V8 Two Wheel Drive Automatic

I replaced my a/c compressor and Charged the system it was working great. 2 Days later I went back to use and no A/C. I since then checked pressure system is holding freon I checked the a/c fuse its ok and the relay I changed out just to make sure that is operating correctly. I also jumped the high side pressure switch and all this will do is turn on the second A/C fan but I am still not getting 12 Volts at the compressor so the clutch is not coming on. My question is there anything else that would keep the compressor from receiving power? (Like the in dash switch?) Or is there something else?

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

On many systems, the compressor will not turn on if the refrigerant is low because the "low pressure safety switch" prevents the compressor clutch from engaging if system pressure is low. This protects the compressor from possible damage caused by a lack of lubrication.

One of the first things you should check, therefore, is compressor engagement. If the compressors magnetic clutch is not engaging when the A/C is turned on, the problem may be a blown fuse or a wiring problem. If the fuse is blown, replacing it may restore cooling temporarily. But the underlying reason for the fuse blowing in the first place needs to be identified and corrected to prevent the same thing from happening again.

If the magnetic clutch is receiving voltage but is not engaging the compressor, the clutch is defective and needs to be replaced. If there is any evidence of leakage around the compressor shaft seal, the seal should also be replaced.

If the clutch works but fails to turn the compressor (the belt may squeal in protest!), The compressor has seized and needs to be replaced.