Pacifica V6-3.8L VIN L (2005)
Air Door Actuator / Motor: Description and Operation
Front Mode Door Actuator
Mode Door Actuator
The mode door actuator for the heating-A/C system is a reversible, 12-volt Direct Current (DC), servo motor. The single mode door actuator is located
on the driver side end of the HVAC air distribution housing, close to the top of the housing. The mode door actuator is mechanically connected to the
mode-air doors.
The mode door actuator is interchangeable with the actuators for the blend-air doors and the recirculation-air door. Each actuator is contained within an
identical black molded plastic housing with an integral wire connector receptacle. Each actuator also has an identical output shaft with splines that
connects it to its respective door linkage and two integral mounting tabs that allow the actuator to be secured to the HVAC housing. The mode door
actuator does not require mechanical indexing to the mode-air doors, as it is electronically calibrated by the A/C-heater control.
The A/C-heater control must be recalibrated each time an actuator motor is replaced.
The mode 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 mode door actuator can move the mode-air doors 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 mode-air doors will move in one direction. When the A/C-heater control reverses the
polarity of the voltage to the motor, the mode-air doors move in the opposite direction.
When the A/C-heater control makes the voltage to both connections high or both connections low, the mode-air doors stop and will not move.
The A/C-heater control uses a feedback signal positioning system to monitor the operation and relative position of the mode door actuator and the mode-
air doors. The A/C-heater control learns the mode-air doors stop positions during the calibration procedure and will store a diagnostic trouble code
(DTC) for any problems it detects in the mode door actuator circuits.
The mode door actuator is diagnosed using a DRBIII(R) scan tool.
The mode door actuator cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.