A/c compressor frozen only when not used?

I never encountered this problem before. 1997 Pontiac Bonneville 3.8L non supercharged. A/C works like brand new. With the a/c on, everything works normally. When the a/c is off the pulley is frozen %26amp; the serpentine belt just spins around the pulley.





Here's the problem. I took the belt off %26amp; i could easily turn the pulley. Put the belt back on, same result as stated above...frozen. I even disconnected the a/c electrical plugs(both). Disconnecting the belt isn't an option on this vehicle. The one belt drives everything else. Has anyone ever experienced this sort of problem?

A/c compressor frozen only when not used?
Your Ac compressor clutch is bad, check for lateral movement of the compressor pully with the belt off. aslo on some models compressor clutch can replaced without replacing thr whole compressor.