Grand Cherokee 2WD V8-5.2L VIN Y (1998)
Blower Motor Resistor: Description and Operation
Blower Motor Resistor
Models with the standard manual temperature control system have a blower motor resistor. The blower motor resistor is mounted to the bottom of
the heater-A/C housing, under the instrument panel and just inboard of the blower motor. It can be accessed for service without removing any
other components.
The resistor has multiple resistor wires, each of which will reduce the current flow to the blower motor to change the blower motor speed by
changing the resistance in the blower motor ground path. The blower motor switch directs the ground path through the correct resistor wire to
obtain the selected 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.
