Blower Motor Resistor: Operation

WARNING: This page is about a different car, the 2005 Dodge Grand Caravan, 2005 Dodge Caravan, and 2005 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.

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

The blower motor control in the manual temperature control system directs the ground path for the front blower motor through the correct resistor wire to obtain the selected speed. With the blower motor control in the lowest speed position, the ground path for the front blower motor is applied through all of the resistor wires. Each higher speed selected with the blower motor control applies the blower motor ground path through fewer of the resistor wires, increasing the blower motor speed.

The front blower motor resistor cannot be adjusted or repaired and, if faulty or damaged (such as a cracked ceramic heat sink), it must be replaced.