Air Temperature Actuator

When the temperature switch is moved to a desired temperature, a signal is sent from the HVAC control module to the air temperature actuator through the air temperature door control circuit. When the logic inside the actuator receives the signal, the air temperature actuator moves info the desired mode. The motor opens the air mixture door to a position to divert sufficient air past the heater core to achieve the desired vehicle temperature. The air temperature actuator has 21 different door positions.

The rear fuse block provides power to the air temperature actuator through the ignition 3 voltage circuit. Ground is provided by the low reference, the HVAC control module and ground circuits.

The air temperature actuator is a DC motor, 0 volts drives the actuator in one direction while 12 volts moves the actuator in the opposite direction. A 12 volt signal is sent out over the air temperature door control circuit, from the HVAC control module, to the air temperature actuator. When the air temperature setting is selected, the logic inside the actuator is used to determine the air temperature door position signals value. The motor moves the air temperature door to the desired temperature. When servicing the actuators, make sure you use the correct service part number. There are specific parts for the left and right side of the HVAC module. Using the wrong part will effect air temperature operation. Circuit 733 (LT BLU) is a feedback circuit used only by the component supplier during their manufacturing process. It is not connected in the vehicle and is not used for diagnostic purposes.