HVAC Blower Controls

The Blower Motor's speed is controlled by the Blower Switch in the Heater-A/C and Rear Defogger Control Assembly. With the switch in the LO position, all of the Blower Resistors are in the circuit with the motor so that it runs slowly. In the M1 and M2 positions, the Blower Switch bypasses some of the resistors, increasing the motors speed.

The Blower Motor is fed through the contacts of the High Blower Relay. When the Blower Switch is in the HI position, battery voltage is supplied through the ORN wire to the coil of the High Blower Relay. The relay is energized and its contact supplies battery voltage directly to the Blower Motor from Fusible Link B.

When the Mode Selector is in the OFF position, no voltage is applied to the Blower Switch and Motor, so the blower does not run. In all other positions, the blower should operate as described.