Blower Motor Relay: Description and Operation

BLOWER MOTOR RELAY
Front
The front blower motor relay is a International Standards Organization (ISO)-type relay. The relay is an electromechanical device that switches battery current from a fuse in the Power Distribution Center (PDC) directly to the blower motor. The relay is energized when the relay coil is provided a ground signal by the blower switch. This arrangement reduces the amount of battery current that must flow through the ignition switch.

The blower motor relay control circuit is protected by a fuse located in the fuse block. When the relay is de-energized, the blower motor ground path through the high blower relay is interrupted.


The front blower motor relay is located in the PDC in the engine compartment.

The blower motor relay cannot be repaired and, if faulty or damaged, it must be replaced.

Rear
The blower motor relay for the optional rear heater-A/C unit is a International Standards Organization (ISO)-type relay. The relay is energized when the relay coil is provided a ground signal by the blower switch. This arrangement reduces the amount of battery current that must flow through the blower switch.

The blower motor relay control circuit is protected by a fuse located in the junction block. When the relay is de-energized, the blower motor ground path through the high blower relay is interrupted.

The rear blower motor relay is located in a connector that is secured to the back of the rear heater-A/C unit housing in the passenger compartment.
The blower motor relay cannot be repaired and, if faulty or damaged, it must be replaced.

HIGH SPEED BLOWER MOTOR RELAY
Front
The front blower motor electrical circuit uses a high speed blower motor relay. The high speed blower motor relay is a International Standards Organization (ISO)-type relay The relay is a electromechanical device that switches the blower motor to ground, bypassing the remainder of the blower motor feed circuit.

The high speed blower motor relay is energized when the relay coil is provided a ground signal by the blower motor switch, and a battery feed from the ignition switch. When the relay is de-energized, the front blower motor ground feed is routed through the front blower motor switch and the blower motor resistor.

The front high speed blower motor relay is located in the engine compartment, on a bracket that is secured under one of the screws for the top cover on the inboard side of the heater-A/C housing. The high speed blower motor relay cannot be repaired and, if faulty or damaged, it must be replaced.

Rear
The optional rear heater-A/C unit blower motor electrical circuit uses a high speed blower motor relay. The high speed blower motor relay is a International Standards Organization (ISO)-type relay. The relay is a electromechanical device that switches the blower motor to ground, bypassing the remainder of the blower motor feed circuit.

The high speed blower motor relay is energized when the relay coil is provided a ground signal by the blower motor switch, and a battery feed from the ignition switch. When the relay is de-energized, the rear blower motor ground feed is routed through the rear blower motor switch and the blower motor resistor.

The rear high speed blower motor relay is located in a connector that is secured to the back of the rear heater-A/C unit housing in the passenger compartment.

The rear high speed blower motor relay cannot be repaired and, if faulty or damaged, it must be replaced.