Actuator-Mode Door: Operation
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 floor, defrost/demist and the panel-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 moves 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 pulse-count 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 position during the calibration procedure and will store a diagnostic trouble code (DTC) for any problems it detects in the mode door actuator circuits.
Refer to HEATING AND A/C SYSTEMS and to HVAC - ELECTRICAL DIAGNOSTICS for more information.
The mode door actuator cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.