Dakota 4WD V8-4.7L (2009)
Blower Motor Resistor: Description and Operation
Operation
OPERATION
The blower motor resistor has multiple resistor wires, each of which will reduce the current flow through the blower motor to change the blower motor
speed. 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 speed control in the MTC heating-A/C system directs the ground path for the blower motor through the correct resistor wire to obtain
the selected speed. With the blower motor speed control in the lowest speed position, the ground path for the blower motor is applied through all of the
resistor wires. Each higher speed selected with the blower motor speed control applies the ground path through fewer of the resistor wires, increasing the
speed of the blower motor.
The blower motor resistor cannot be adjusted or repaired and must be replaced if inoperative or damaged (such as a cracked ceramic heat sink).
