Blower Motor: Description and Operation

CIRCUIT OPERATION
Power for the blower motor is supplied on circuit C1. This circuit is protected by a 30 Amp fuse in cavity 9 of the fuse block and HOT when the ignition switch is in the RUN position only. Power for the fuse is supplied on circuit A38 from the ignition switch.

Power for the A38 circuit is supplied on circuit A1. This circuit is protected by a fusible link located near the auxiliary jumper post on the left toe box.

The blower motor in this Vehicle runs continuously in the LOW speed when the ignition switch is in the RUN position, and a ground path is provided through the CLOSED heat mode switch.

When the blower motor switch is in the M1 position, battery voltage is passed through the blower motor on circuit C1 to circuit C4. Circuit C4 connects from the blower motor to the blower motor resistor and the blower motor switch.

Power is passed through the switch to the blower motor resistor on circuit C5. The voltage is passed through the series of resistors to circuit C7.

The C7 circuit connects from the resistor to the heater ON/OFF switch, located in the mode select switch. The switch is then connected to ground on circuit Z1.

Operation of the M2 circuit is the same except circuit C6 is connected between the blower motor switch and the blower motor resistor.

In the HIGH speed mode there are no resistors used. Voltage is passed through the motor and the switch on circuit C7 to the heater ON/OFF switch. Then through the switch to ground on circuit Z1.