Principles of Operation

Rear View Mirrors - Exterior


Principles of Operation

The movement of the LH and RH exterior mirror glass is controlled by the exterior mirror control switch and the LH and RH exterior mirror motors. Adjusting the exterior mirror switch to the LH or RH position determines which exterior mirror motor will be controlled.

The exterior mirrors use a jumper harness between the vehicle wire harness connector and the exterior mirror motor. The exterior mirror jumper harness is integral to the exterior mirror. Before replacing an exterior mirror or mirror motor, inspect the jumper harness for open and shorted circuits or damaged and pushed-out pins. If a concern with the exterior mirror jumper harness exists, an attempt to repair the jumper harness should be made.

Only vehicles equipped with memory exterior mirrors are capable of setting DTCs.

Power Exterior Mirrors - Without Memory

When the exterior mirror control switch is adjusted to the left, right, up or down position, the exterior mirror control switch will supply voltage and ground to the selected exterior mirror motor to move the exterior mirror glass to the desired position.

Memory Exterior Mirrors

The memory mirror function recalls the preferred positioning of the exterior mirrors. Memory is activated by the door mounted switches or the Remote Keyless Entry (RKE) transmitter. The Driver Seat Module (DSM) constantly tracks the exterior mirror position by using the potentiometers in the exterior mirror assembly. The positions remain in memory as long as the DSM retains power. When a memory position is recalled by the operator, the DSM powers the exterior mirror motors simultaneously and monitors the potentiometer circuits. When the stored memory position is reached, the DSM removes the voltage from the motors. If the exterior mirror control switch is operated during a memory recall, the DSM stops the recall and responds to the exterior mirror control switch command.

For information on the DSM and Memory Position Programming, refer to Seats.

Heated Exterior Mirror

The rear window defrost switch controls the operation of the heated exterior mirror glass. The heated exterior mirror glass only operates when the rear window defrost system is ON. The heated exterior mirror glass voltage is supplied by the heated mirror relay through Battery Junction Box (BJB) fuse 28 (15A).

LH Auto-Dimming Exterior Mirror

The LH exterior mirror may be equipped with an auto-dimming feature. This feature automatically reduces the glare caused by headlamps reflecting in the mirror. The interior auto-dimming rear view mirror controls the reflectance level of the LH exterior mirror to eliminate unwanted glare. The reflectance level of the mirror glass is variable and depends on the amount of rear glare in relation to ambient light conditions in front of the interior mirror. To provide increased visibility when backing up, the interior rear view mirror glass and LH exterior mirror glass will automatically return to a high reflectance mode whenever the selector lever is placed in REVERSE.

For information and diagnostics, refer to Rear View Mirrors - Interior.