The automatic day/night mirror uses two photocell sensors, located on the rear view mirror, to determine light conditions in the front and back of the vehicle. At night, as the glare of headlamps from behind increases, the mirror gradually becomes darker to absorb the glare. In the daytime, the mirror is in a clear state.
With the ignition switch in the ON position, battery positive voltage (B+) is applied to the automatic day/night mirror connector cavity 1 via CKT 41 (BRN). When the automatic day/night mirror switch is placed in an ON position, battery positive voltage (B+) is applied to the automatic day/night mirror circuit. Battery positive voltage (B+) is supplied at all times to the REVERSE Relay coil through the rear fuse block. Battery positive voltage (B+) is supplied at all times to the REVERSE Relay switch through the NSBU Fuse through the rear fuse block. The powertrain control module (PCM) sends a Class 2 message to the rear integration module (RIM) indicating that ignition switch is in the ON position and the gear selector lever is in the REVERSE position. When these conditions occur, the RIM pulls CKT 646 (LT GRN) to ground, which grounds the coil of the REVERSE Relay. The coil is energized, closing the switch contacts. This supplies battery positive voltage (B+) to the automatic day/night mirror connector cavity 3 via CKT 24 (LT GRN). The mirror will gradually change to a clear state as a result of the reverse input.
The LH outside mirror also has glare reduction dimming that is controlled by the interior mirror. The tint level voltage (0 - 1.2 V) is supplied to the LH outside mirror via CKT 1690 (GRY/BLK) or (GRY) and CKT 1691 (PNK) through the Driver Door Module. The LH outside mirror darkens or clears along with the interior mirror.
Compass
The compass is an internal, non-servicable part of the automatic day/night mirror. It determines the direction that the car is heading by the Earth's magnetic field. The compass zone must match the zone in which the car is located for the compass to display the proper heading. Refer to Compass Variance Setup . The compass may also need calibrating. It has manual and automatic calibration. Refer to Compass Calibration Description .
