Circuit/System Description
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The HVAC control module controls the HVAC door actuators to regulate the airflow through the HVAC system. Each actuator consists of an electric motor and a potentiometer. The module supplies a low reference and 5-volt reference source voltage to the potentiometer. The HVAC control module monitors the voltage drop across the potentiometer on the door position signal circuit. When the actuator shaft rotates, the voltage on the door position signal circuit changes. The control circuit uses either a 0, 2.5 or 5-volt signal to command the actuator movement. When the actuator is at rest, the control circuit value is 2.5 volts. A 0 or 5-volt control signal commands the actuator movement in opposite directions.
- B0228 is for the recirculation actuator.
- B0413 is for the drivers air temperature actuator.
- B0423 is for the passenger air temperature actuator.
- B0433 is for the auxiliary air temperature actuator.
- B3779 is for the mode actuator.
- B3782 is for the auxiliary mode actuator.