If you have less than 150K miles on the car, call up the dealer and ask them about Extended Coverage Program 01M07 to see if you are covered. You may well have a heater blower switch malfunction. One way to confirm is to test the Violet/Orange wire at the A/C pressure switch end. If it doesn't have power, there is a good chance the heater blower switch or wiring from, is the problem.
