Principles of Operation

PRINCIPLES OF OPERATION

The exterior mirror control switch is located on the LH door trim panel. Adjusting the exterior rear view mirror control switch to the LH or RH position determines which exterior mirror glass will be controlled. Power is supplied to the exterior mirror switch from the smart junction box (SJB). If equipped with power folding mirrors, the center position of the exterior mirror control switch controls the power folding mirrors. Only vehicles equipped with memory exterior rear view mirrors are capable of setting DTCs.

Heated Exterior Mirrors
The rear window defrost switch controls the operation of the heated exterior mirrors. The heated exterior mirrors only operate when the rear window defrost is ON. The heated exterior mirror power is supplied by the rear window defrost relay through battery junction box (BJB) fuse 23 (15A), which isolates the heated exterior mirrors from the rear window defrost system in the event of a concern.

Memory Exterior Mirrors
The memory exterior mirror function is controlled by the driver seat module (DSM). The memory exterior mirrors feature allows the driver to program personalized mirror positions that can be recalled using the memory switches or remote transmitter. There are 2 memory settings possible. The power driver seat positions are also stored and recalled with the memory exterior mirror positions. The memory mirror function recalls the preferred positioning of the exterior mirrors when the transmission is in the PARK or NEUTRAL position and the door mounted switches or the remote keyless entry (RKE) transmitter are activated. The 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. 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 Seats.

Power Folding Mirrors

NOTE:
- The power folding mirrors must be synchronized any time the mirrors are folded or unfolded without using the mirror control switch, or if a new power folding mirror has been installed. Refer to Exterior Mirror Motor Synchronization - Power Folding. Programming and Relearning
- 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 will result 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 from 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 will 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 will disable the system for approximately 2 minutes to prevent damage to the power folding mirror drive motors. After 2 minutes have elapsed, normal operation will resume. Before running a self-test or retrieving DTCs, the power fold switch must be inactive for at least 30 seconds.

Interior Auto-Dimming Rear View Mirror
The interior rear view mirror may be equipped with an auto-dimming feature. The interior auto-dimming rear view mirror automatically reduces the glare caused by headlamps reflecting in the interior rear view mirror. Power is supplied to the interior auto-dimming mirror when the ignition is in the RUN position or the accessory delay is active. The auto-dimming feature is disabled when the vehicle is in REVERSE.

The interior auto-dimming rear view mirror has 2 photoelectric sensors, a forward facing sensor and a rearward facing sensor, that detect forward and rearward light conditions. Based on these inputs, the automatic dimming feature adjusts the reflectance level of the interior rear view mirror glass 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.

When the forward sensor detects daytime conditions, the rearward sensor is inactive and the interior rear view mirror stays in a high reflectance mode. When the forward sensor detects nighttime conditions, the rearward sensor is active and detects glare from the headlights of vehicles approaching from the rear or other glare-producing light sources. To provide increased visibility when backing up, the interior rear view mirror will automatically return to a high reflectance mode whenever the vehicle is in REVERSE.

If the forward or rearward sensors are blocked, the interior auto-dimming rear view mirror might not work correctly.

Interior Rear View Mirror With Video Display
For vehicles that are equipped with a rear-mounted object detection camera, a video image will be displayed on the LH side of the interior rear view mirror glass when the transmission is in the REVERSE position. For the rear-mounted object detection Description and Operation, service procedures or Diagnosis and Testing, refer to Collision Avoidance and Parking Assist Systems.

Turn Signal Mirror
The exterior mirror may be equipped with a mirror-mounted turn signal assembly. For the mirror-mounted turn signal Description and Operation, service procedures or Diagnosis and Testing, refer to Lighting and Horns.

Puddle/Approach Lamps
The 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 remote transmitter, if equipped. For the mirror-mounted puddle lamp Description and Operation, service procedures or Diagnosis and Testing, refer to Lighting and Horns.