The automatic day/night feature of the driver outside rearview mirror is controlled by the inside rearview mirror. The inside rearview mirror supplies a signal and a low reference to the driver outside rearview mirror. The voltage on the signal circuit of the driver outside rearview mirror varies between 0.5-1.5 volts depending on light conditions present at the inside rearview mirror. At night, with the automatic day-night feature enabled, the driver outside rearview mirror will automatically darken with the inside rearview mirror to reduce the glare from the headlamps from behind. The voltage on the signal circuit of the driver outside rearview mirror will be near 1.5 volts. In daytime conditions, the mirrors are in the normal state. The voltage on the signal circuit of the driver outside rearview mirror may be less than or near 0.5 volts.

Schematic Reference

Inside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Automatic Day-Night Mirror Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information.

Headlamps ON, vehicle in PARK, cover the front light sensor with a towel or other suitable item. Shine a flashlight at the rear light sensor while observing the left outside rearview mirror face. The left outside rearview mirror face should dim.

Outside Rearview Mirror Dimming Malfunction

1. Ignition OFF, disconnect the X2 harness connector at the driver outside rearview mirror.
2. Test for less than 10 ohms between the low reference circuit terminal 4 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, test or replace the inside rearview mirror.

3. Ignition ON, test for less than 1 volt between the signal circuit terminal 5 and ground.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, test or replace the inside rearview mirror.

4. Headlamps ON, vehicle in PARK, cover the front light sensor with a towel or other suitable item. Shine a flashlight at the rear light sensor. Test for greater than 1 volt between the signal circuit terminal 5 and ground.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the inside rearview mirror.

5. If all circuits test normal, test or replace the outside rearview mirror glass.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.