The blower located behind the glove box only operates on high speed. It doesn't matter if the control is in heating or cooling. I swapped out the speed controller with another and no change. Also, the ac pilot light only lights up when the blower is on high speed. I unplugged the blower and measured the voltage to be 13.5 volts regardless of the speed selector switch position. I also noticed if the blower is unplugged, the ac pilot light lights up on all the speed settings. The high speed only issue was a sudden change, not a gradual change. Any thoughts or ideas would be greatly appreciated. DodgeInLaw

 

no other speeds on blower fan?