Blower Controls

The blower motor is controlled by the climate control unit which receives battery voltage at all times through fuse 56. With the ignition switch in RUN, battery voltage is supplied to the control unit through fuse 19. The control unit is grounded at G303.


Battery voltage to the [1][2]blower motor relay contacts is applied through fuse 37 at all times. With the ignition switch in RUN, the blower motor relay is energized and battery voltage is supplied to the blower motor. The power transistor controls the blower motor in all speeds except HIGH. The power transistor is controlled by the control unit. When HIGH blower speed is requested,the climate control unit grounds the blower motor "high" relay coil, the relay is energized, and the blower motor is connected directly to ground which makes the blower run at HIGH speed.

When the climate control unit is in the auto mode and requests heat, the blower motor will not turn on until the engine coolant is warm (radiator fan comes on).