i have a 91 deville. there is no power going to the plug for the pump. i checked the fuse under the hood and that is good.i dont know what else to check.

 

BCM can disable a/c. Check for codes and clear or disconnect battery for 10 sec., then re-connect and see if compressor will engage. Low freon will set code and disable compressor/pump. Compressor relays did tend to fail during the early 90's.

 

problem solved..thanx