The automatic air cond/heater failed. The controls would not light up and none of the buttons(ie mirror heater, rear window heat) would function. The dealer said the control needed replacement. I replaced it with a new BMW part. That seemed to do the trick, the unit functions and both heat and air work. How ever the button for the rear view mirror heat and rear window hear is blinking and both are on when ever the car is running. I have disconnected and reconnected the car battery hoping that would help but it had no effect. The only way to shut off the heat was to pull the fuses for the Air cond/ heater controls(I tried to isolate the fuses for the mirrors and rear window but when the fuses were pulled the car would not start). Any one have any ideas?