Circuit Description
WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue. However, it is still accessible from the selected car via links, so may be relevant.
The HVAC control module commands the right air temperature actuator to move by controlling the voltage supplied on the control circuit. A low voltage of zero volts moves door toward full hot. A voltage of 2.5 volts stops the door. A high voltage of 5 volts moves the door toward full cold. The HVAC control module determines the current position of the actuator by monitoring the voltage on the signal circuit. The feedback potentiometer is a function of the motor position. A high voltage of 4-5 volts indicates full cold door position. A low voltage of less than one volt indicates full hot door position. The HVAC control module controls the right air temperature actuator door positions in order to maintain the selected air temperature.