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Control Module HVAC: Description and Operation

SYSTEM OPERATION
The blower motor power module is only used in vehicles equipped with Automatic Temperature Control (ATC). it is located on the lower right side of the HVAC unit housing.

The power module receives pulse width modulated signals from the Body Control Module. The power module varies voltage to the blower motor for different blower speeds based on the ATC software. There are 14 speeds and a blower off signal.