RAM 2500 Truck 4WD V10-8.0L VIN W (1997)
Blower Motor Resistor: Description and Operation
Fig 40 Blower Motor Resistor -- Typical
The blower motor resistor is mounted to the heater-A/C housing, under the instrument panel and just inboard of the blower motor. It can be accessed
without removing any other components.
The resistor has multiple resistor wires, each of which will change the resistance in the blower motor ground path to change the blower motor speed. The
blower motor switch directs the ground path through the correct resistor wire to obtain the selected blower motor speed.
With the blower motor switch in the lowest speed position, the ground path for the motor is applied through all of the resistor wires. Each higher speed
selected with the blower motor switch applies the blower motor ground path through fewer of the resistor wires, increasing the blower motor speed.
When the blower motor switch is in the highest speed position, the blower motor resistor is bypassed and the blower motor receives a direct path to
ground.
The blower motor resistor cannot be repaired and, if faulty or damaged, it must be replaced.
