Blower Motor: Description and Operation

Battery voltage is supplied through fuse 35 to the blower motor relay contacts at all times. With the ignition switch in ON (II), voltage is applied to the coil of the blower motor relay through fuse 9, and the relay energizes, providing power to the blower motor. The blower motor ground path is completed when the blower switch is turned to positions LO, M1, or M2. The ground path includes one or more of the blower motor resistors. As you move the switch from LO through M2, resistors are bypassed. Decreasing the resistance increases the voltage across the blower motor. This increases the blower motor speed. When you move the blower switch to the MAX position, all of the resistors are bypassed and the blower motor runs at full speed.