Cadillac Repair: A/C repair on Cadillac Deville, electronic leak detector, cadillac deville

Question
My 70 yr old mother-in law owns a 1997 Cadillac Deville with a 32 Valve North Star Engine.  The A/C is not blowing cold air.  My husband checked the freon and the system shows to be full, but it says the compressor is off.  Is there a way to re-set the system?  Also, it states in the repair manual that you must add coolant pellants to the radiator.  Can you tell me what kind of pellets it is talking about and where we can buy them?  Is this something that is necessary to make the A/C run cold?

Answer
The pellets have NOTHING to do with the AC. There is NO WAY that you can tell that you have the full amount of freon in the system unless the compressor is running and you have a set of AC gagaes. You most likely have a freon leak somewhere in the system that needs to be found via an electronic leak detector.