DESCRIPTION

Fig. 59: Rear Blower Power Module Description

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

The rear blower motor power module (1) is mounted to the inboard side of the rear heating-A/C housing, located on the right side of the vehicle. The rear blower motor power module consists of a molded plastic housing with two integral wire connector receptacles (2) for the power module electronic circuitry, a mounting plate (3) with a gasket and a finned aluminum heat sink (4).

The rear blower motor power module can be accessed for service without removing the rear heater-A/C housing.

OPERATION

The rear blower motor power module is connected to the vehicle electrical system through a dedicated lead and connector of the rear body wire harness. A second lead and connector of the wire harness is connected to the rear blower motor. The rear blower motor power module allows the microprocessor-based automatic temperature contro (ATC) A/C-heater control to calculate and provide infinitely variable blower motor speeds based upon either manual blower switch input or the ATC programming using a pulse width modulated (PWM) circuit strategy.

The PWM voltage is applied to a comparator circuit which compares the PWM signal voltage to the rear 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 rear blower motor power module is diagnosed using a scan tool.

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

REMOVAL

Fig. 60: Rear Blower Power Module Removal/Installation

1. Disconnect and isolate the negative battery cable.

2. Remove right rear quarter trim panel.

3. Disconnect the two wire harness connectors (4) from the rear blower motor power module (3).

4. Remove the two screws (1) that secure the rear blower motor power module to the rear heater-A/C housing (2) and remove the module.

INSTALLATION

Fig. 61: Rear Blower Power Module Removal/Installation

1. Position the rear blower motor power module (3) onto the rear heater-A/C housing (2).

2. Install the two screws (1) that secure the rear blower motor power module to the rear heater-A/C housing.

Tighten the screws to 1.2 N.m (10 in. lbs.).

3. Connect the two wire harness connectors (4) to the rear blower motor power module.

4. Install the right rear quarter trim panel.

5. Reconnect the negative battery cable.