Description And Operation: Operation
The blend door actuator is connected to the HVAC module by a dedicated five-wire lead and connector of the HVAC wire harness. The blend door actuator can move the blend-air doors in two directions. When the HVAC module pulls the voltage on one side of the motor connection high and the other connection low, the blend door actuator will move in one direction. When the HVAC module reverses the polarity of the voltage to the motor, the blend door actuator moves in the opposite direction. Once the HVAC module makes the voltage to both connections high or both connections low, the blend door actuator stops and will not move.
The blend door actuator contains a potentiometer, which the HVAC module uses to monitor the relative position of the blend-air doors. The HVAC module learns the blend-air door stop positions during the calibration procedure and will store a Diagnostic Trouble Code (DTC) for any problems it detects in the blend door actuator circuits. Refer to HEATING & AIR CONDITIONING - DIAGNOSTIC CODE INDEX .
The blend door actuator cannot be adjusted or repaired and must be replaced if inoperative or damaged.