GMC Repair: A/C is not working, 2005 buick lacrosse, buick lacrosse

Question
I have a 2005 Buick Lacrosse(3.8L V-6).
When I turn on the A/C the clutch for the compressor is not engaging. There is warm air coming through the vents.
I was thinking of replacing the A/C compressor control relay.
I checked the level of freon and is full.
Your help would be greatly appreciated.

Thanks

David

Answer
You need to check your compressor with the switched bypassed. I checked mine by going straight from the battery to the compressor. If the clutch engages it could be the switch or the relay. You could replace the relay, but I would try that first. Second thing I would do, if not first, have the codes scanned or you can do that yourself as well. You can purchase a code reader from your local auto store in the range of: $30-$200