I recently heard 3 or 4 “clicks” from under my dash around where the heater control is. Since then the blower will blow vent and A/C air but when the control is set to heat, it will not blow heat. I don’t suspect the thermostat because this problem coincided with the clicking. Is there a separate relay for the heater or could the heater control switch be the problem?? (FYI - there is plenty of antifreeze, so that’s not it either)
It sounds like what you may have heard is the vent door. It appears the door is stuck in the wrong position.
click,click,click…= blend door motor. ( Inside motor is little plastic reduction gears much like in a clock. They’re only plastic so if the door binds, the gears strip. )
Ford # XF2Z-19E616-FB , Motorcraft # YH-1764 , $59.95
You don’t say what year but 1999-2003 is the one I listed.
Question when replacing a blend door motor, What caused the door to bind to ruin the motor ?
Clean inside to be sure door moves freely.