Module, Power, Blower Motor: Operation

The blower motor power module is connected to the vehicle electrical system through a dedicated lead and connector of the instrument panel wire harness. A second lead and connector of the instrument panel wire harness is connected to the blower motor.

The blower motor power module allows the microprocessor-based A/C heater control to provide an infinite amount of blower motor speeds throughout its operating range, based upon blower switch input.

The A/C heater control system uses a Pulse Width Modulated (PWM) circuit strategy. PWM voltage is applied to a comparator circuit which compares the PWM signal voltage to the blower motor feedback voltage. The resulting output drives the power module circuitry, which provides a linear output voltage to change or maintain the desired blower speed.

The blower motor power module is diagnosed using a scan tool. Refer to DTC INDEX (1 OF 2) or DTC INDEX (2 OF 2) .

The blower motor power module cannot be adjusted or repaired and must be replaced if inoperative or damaged.