the field coil is inside the compressor pully, to get to it you would have to take out the compressor, take off the clutch plate and then the pulley...i wouldnt suggest doing that...uh...but the wires coming from the compressor, you can check the resistance of the field coil...get a multimeter have one connector touching the bare metal of the compressor and the other connector to the wire that goes to the condensor fan (disconnect this plug to test)...resistance should be 3.05-3.35 omhs at 68F...if not probably needs to be replaced