Power Module
WARNING: This page is about a different car, the 2002 Dodge Intrepid, 2002 Chrysler Intrepid, 2002 Chrysler Concorde, and 2002 Chrysler 300M. However, it is still accessible from the selected car via links, so may be relevant.
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 housing housing, and is controlled by the Body Control Module (BCM).
The power module receives Pulse Width Modulated (PWM) signals from the BCM. The power module varies voltage to the blower motor for, different blower speeds based on the ATC software. There are 14 selectable speeds, while the auto mode provides 256 variations.