My a/c was blowing cold when we went on a long drive ( 4 hrs up and then next day 4 hrs back )Then next morning all it did was blow hot air. Clutch is in engaging , check freon thats ok,all the a/c lights on dash comes on and so it hasn't worked in 2 weeks. Could it be the thermo control amp that I keep reading here. Thanks for any help. I know it's winter but I live in Florida.