Electronic Climate Control
CLIMATE CONTROL SYSTEM
Blower Controls
The fan speed is automatically controlled in the fully-automatic mode. You can manually select the fan speed by turning the fan control dial clockwise, just past the AUTO position. This takes the fan from automatic mode to its lowest manually controlled speed. Turning the dial further clockwise increases the fan's speed, which increases air flow.
Battery voltage is applied through fuse 56 to the front blower motor relay contacts at all times. With the ignition switch ON (II), the front blower motor relay in the under-hood fuse/relay box is energized which feeds battery voltage to the front blower motor. The blower power transistor controls the front blower motor in all speeds except HIGH. The blower power transistor is controlled by the climate control unit. When the control unit requests HIGH blower speed, it grounds the front blower motor HIGH relay coil, energizing the relay, which connects the front blower motor directly to ground, making the blower run at high speed.
In cold weather, the blower will not come on automatically until the heater starts to develop warm air.