Caravan FWD V6-3.3L VIN 3 Flex Fuel (2001)
Air Door Actuator / Motor: Description and Operation
Mode Door Actuator
Fig.21 Mode Door Actuator
MODE DOOR ACTUATOR - FRONT
The mode door actuator is a reversible, 12-volt Direct Current (DC), servo motor. The single mode door actuator is located on the driver side end
of the heater-A/C housing unit, close to the top of the distribution housing. The mode door actuator is mechanically connected to the mode door.
The mode door actuator is interchangeable with the actuators for the blend air door(s) and the recirculation air door. Each actuator is contained
within an identical black molded plastic housing with an integral wire connector receptacle. Two integral mounting tabs allow the actuator to be
secured with two screws to the heater-A/C unit housing. Each actuator also has an identical output shaft with splines that connects it to the linkage
that drives the mode door. The mode door actuator does not require mechanical indexing to the mode door linkage, as it is electronically calibrated
by the heater-A/C control module. The mode door actuator cannot be adjusted or repaired and, if damaged or faulty, it must be replaced.
The mode door actuator is connected to the heater- A/C control module through the vehicle electrical system by a dedicated two-wire take out and
connector of the HVAC wire harness. The mode door actuator can move the mode door in two directions. When the heater-A/C control module
pulls the voltage on one side of the motor connection.. high and the other connection low, the mode door will move in one direction. When the
module reverses the polarity of the voltage to the motor, the mode door moves in the opposite direction. When the module makes the voltage to
both connections high or both connections low, the mode door stops and will not move. These same motor connections also provide a feedback
signal to the heater-A/C control module. This feedback signal allows the module to monitor the operation and relative position of the mode door
actuator and the mode door. The heater-A/C control module learns the mode door 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 can be diagnosed using a
DRB III scan tool. Refer to the appropriate diagnostic information.
