Operation CHARM: Car repair manuals for everyone.

Control Module HVAC: Description and Operation





The A/C blower motor speed control is located in the A/C evaporator core housing and is accessible through the engine compartment.
^ The function of the A/C blower motor speed control is to convert low power signals from the EATC assembly to a high current, variable ground feed for the blower motor.
^ A/C blower motor speed is infinitely variable and is controlled by the electronic control assembly software and A/C electronic blend door actuator position.
^ A delay function provides a gradual increase or decrease in A/C blower motor speed under all conditions.