Control Module HVAC: Description and Operation

Blower Motor Power Module:

A blower motor power module is used on this model when it is equipped with the optional automatic temperature control (ATC) heating-A/C system. Models equipped with the standard manual temperature control (MTC) heating-A/C system use a blower motor resistor, instead of the blower motor power module.

The blower motor power module is mounted to the bottom of the HVAC housing, directly behind the glove box. The blower motor power module consists of a molded plastic mounting plate with two integral connector receptacles. Concealed behind the mounting plate is the power module electronic circuitry and a large finned heat sink. The blower motor power module is accessed for service by removing the passenger side silencer panel.

The blower motor power module is connected to the vehicle electrical system through a dedicated lead and connector of the HVAC wire harness. A second connector receptacle receives a wire lead connector from the blower motor. The blower motor power module allows the automatic temperature control (ATC) heating-A/C system to calculate and provide infinitely variable blower motor speeds based upon either manual blower switch input or the ATC programming strategy. The body control module (BCM) receives the desired blower speed input from the A/Cheater control and then process the control signal to change or maintain the desired blower speed.

The blower motor power module is diagnosed using a DRBIII (R) scan tool.

The blower motor power cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.