Blower Motor Resistor: Description and Operation

Blower Motor Resistor:

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

The blower motor resistor is mounted to the bottom of the HVAC housing, directly behind the glove box. The blower motor resistor consists of a molded plastic mounting plate with an integral wire connector receptacle. Concealed behind the mounting plate is the resistor circuit board.

The blower motor resistor is accessed for service by removing the passenger side silencer panel.

The blower motor resistor is connected to the vehicle electrical system through a dedicated wire lead and connector of the HVAC wire harness. The blower motor resistor has multiple resistor circuits, each of which will reduce the current flow through the blower motor to change the blower motor speed.

The blower motor switch in the MTC heating-A/C system directs the ground path for the blower motor through the correct resistor circuit to obtain the selected speed. With the blower motor control in the lowest speed position, the ground path for the blower motor is applied through all of the resistor circuits. Each higher speed selected with the blower motor control applies the blower motor ground path through fewer of the resistor circuits, increasing the blower motor speed.

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