Commander 4WD V8-4.7L VIN N (2006)
Air Door Actuator / Motor: Description and Operation
Recirculation Door Actuator
ACTUATOR-RECIRCULATION DOOR
DESCRIPTION
The recirculation door actuator (1) is a reversible, 12 volt direct current (DC), servo motor. The recirculation door actuator is located on the left side of
the HVAC air inlet housing and is directly connected to the pivot shaft of the recirculation-air door.
OPERATION
The recirculation door actuator is interchangeable with the actuators for the blend-air door(s) and the mode-air doors. Each actuator is contained within
an identical black molded plastic housing with an integral wire connector receptacle (2). Each actuator also has an identical output shaft with splines (3)
that connects it to its door linkage and three integral mounting tabs (4) that allow the actuator to be secured to the air inlet housing. The recirculation
door actuator does not require mechanical indexing to the recirculation-air door, as it is electronically calibrated by the A/C-heater control.
The recirculation door actuator is connected to the A/C-heater control through the vehicle electrical system by a dedicated two-wire lead and connector
of the HVAC wire harness. The recirculation door actuator can move the recirculation-air door in two directions. When the A/C-heater control pulls the
voltage on one side of the motor connection high and the other connection low, the recirculation-air door will move in one direction. When the
A/C-heater control reverses the polarity of the voltage to the motor, the recirculation-air door moves in the opposite direction.
When the A/C-heater control makes the voltage to both connections high or both connections low, the recirculation-air door stops and will not move.
The A/C-heater control uses a pulse-count positioning system to monitor the operation and relative position of the recirculation door actuator and the
recirculation-air door. The A/C-heater control learns the recirculation-air door stop positions during the calibration procedure and will store a diagnostic
trouble code (DTC) for any problems it detects in the recirculation door actuator circuits.
The recirculation door actuator cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
