Principles of Operation

Rear View Mirrors - Exterior

Principles of Operation

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

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 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, attempt to repair the jumper harness.

Vehicles equipped with memory exterior mirrors are capable of setting DTCs.

Power Exterior Mirrors - Without Memory

Exterior mirror glass logic is the selected request from the exterior mirror control switch. When the switch is adjusted to the left, right, up or down position, voltage and ground is supplied to the selected exterior mirror motor to move the exterior mirror glass to the desired position.

Memory Exterior Mirrors

LH and RH exterior mirror glass movement is controlled by the exterior mirror control switch, Driver Seat Module (DSM) and the LH and RH exterior mirror motors. Adjusting the switch to the LH or RH position determines which exterior mirror motor to control. The switch sends voltage and ground input signals to the DSM. The DSM provides voltage and ground to the appropriate exterior mirror motor to move the selected exterior mirror glass to the desired position.

The memory function recalls the preferred position of the exterior mirrors when the gear selector is in PARK or NEUTRAL or the Remote Keyless Entry (RKE) transmitter is activated. The DSM constantly tracks the exterior mirror motor position using potentiometers located internal to the exterior mirror motors. When a memory position is recalled, 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 and ground 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. The DSM is capable of setting a DTC for the memory mirror system when a system concern exists.

For information on the DSM and memory position programming, refer to Seating Description and Operation.

Heated Exterior Mirror

The heated exterior mirror glass operates when the defrost system is activated by the defrost switch or remote start, if equipped. The heated exterior mirror glass voltage is supplied by the rear window defrost relay through Battery Junction Box (BJB) fuse 32 (40A).

On vehicles equipped with a power sliding rear window with rear defrost, the defrost switch LED does not illuminate unless the rear sliding window glass is in the fully CLOSED position.

On vehicles equipped with a LH auto-dimming exterior mirror, the glass is thicker than the standard mirror glass. As a result, it takes longer for a LH auto-dimming exterior mirror to defrost than a RH heated exterior mirror.

LH Auto-Dimming Exterior Mirror

The LH exterior mirror is equipped with an auto-dimming feature. This feature automatically reduces the glare caused by headlamps reflecting in the mirror. The interior auto-dimming mirror controls the reflectance level of the LH exterior mirror. 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 mirror glass and LH exterior mirror glass 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 Special Tool(s) Used With Diagnostics.

Power Folding Mirrors

NOTE: The power folding mirrors may need to be synchronized when the RH, LH or both power folding mirrors are folded manually, and then folded inward using the power folding mirror control switch. Refer to Exterior Mirror Motor Synchronization - Power Folding Programming and Relearning.

NOTE: Before running a self-test diagnostic or retrieving DTCs, the power fold switch must be inactive for at least 30 seconds. Retrieving DTCs before 30 seconds results in false DTCs.

The power folding exterior mirrors are controlled by the DSM. The power folding exterior mirror feature allows both exterior mirrors to be folded or unfolded using the exterior mirror control switch. When the exterior mirror control switch is set to the center position and pressed rearward to the FOLD/UNFOLD position, the exterior mirror control switch sends a signal to the DSM which then supplies power and ground to the exterior mirrors to fold or unfold the mirrors. The RH and LH power folding mirrors fold or unfold at the same time and cannot be controlled independently. The power folding mirrors contain a drive motor that is not replaceable. If a power folding mirror drive motor is found to be inoperative, a new power folding exterior rear view mirror assembly must be installed.

If the power folding mirrors are folded or unfolded continuously (6 to 10 cycles), the power lockout feature disables the system for approximately 3-10 minutes to prevent damage to the power folding mirror drive motors. After 3-10 minutes have elapsed, normal operation resumes. Before running a self-test or retrieving DTCs, the power fold switch must be inactive for at least 30 seconds.

Turn Signal Mirror

The LH and RH exterior mirrors may be equipped with a mirror-mounted turn signal assembly.

Puddle/Approach Lamps

The LH and RH exterior mirrors may be equipped with approach or puddle lamps, which will illuminate when the interior lights are turned on by opening a door or by pressing the unlock button on the transmitter, if equipped.