Think you may have too much gas by weight ?? in the AC system causing the compressor to lock up but their should be a safety valve that will blow the gas out of the compressor ?? i have never seen one of these vehicles except on the tv so iam not the best person to answer but could it have a climatic computer ?? if so run a wire from the switch direct to the compressor this will by pass the computer .sorry but iam british living in spain and these cars are just not seen over here.It could even be its working too well and freezing in the resistrictor valve to be honest i would need to have the vehicle in front of me then i could diagnose it correctly and hit it with the approiate size hammer to fix it