Dakota 4WD V6-239 3.9L Magnum (1996)
Blower Motor: Description and Operation
CIRCUIT OPERATION
When the ignition switch is in the RUN position, circuit A2 from fuse E in the Power Distribution Center (PDC) connects with circuit A22. Circuit
A22 supplies voltage to a bus bar in the fuse block that powers fuse 1. Fuse 1 protects circuit C1 which supplies battery voltage to the blower
motor.
The ground path for the blower motor is through circuit H6 to the blower motor resistor block and then through the fan switch in the A/C heater
controls to circuit Z1. The blower motor resistor block consists of four resistors connected in series.
Each resistor in the blower motor resistor block is spliced to the fan switch on separate circuits; C4, C5, C6, and C7. Depending on fan switch
position, voltage passes through one or more resistors to ground. Blower motor fan speed is controlled by the number of resistors voltage passes
through to ground.
When the fan switch is in the LOW position, circuit C4 provides the ground path. In the M1 position, circuit C5 provides ground. In the M2
position, the ground path is through circuit C6. Circuit C7 provides path for ground when the switch is in the HIGH position.
