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Automatic Day-Night Mirrors Malfunction (with UVC)




Automatic Day-Night Mirrors Malfunction (with UVC)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category

Diagnostic Fault Information






Circuit/System Description

The inside rearview mirror uses 2 photocell sensors. One sensor is the rear light sensor, located on the face side of the mirror, facing the rear of the vehicle. The rear light sensor is used to determine light conditions present at the mirror face. The other sensor is the front light sensor, located on the backside of the mirror, facing the front of the vehicle. The front light sensor is used to determine the exterior light conditions at the front of the vehicle. With a low exterior light condition detected by the front light sensor and a high light condition from the rear light sensor, the inside rearview mirror will automatically darken the face of the inside rearview mirror and the driver outside rearview mirror. The inside rearview mirror provides a signal circuit and a low reference circuit to the driver mirror face to darken the mirror when needed.

With the gear selector lever in the REVERSE position and the engine running, the automatic day-night feature is disabled. This allows the driver to see objects in the mirror clearly when backing up, regardless of the rear light sensor status. The reverse signal is provided to the mirror through serial data.

Reference Information

Schematic Reference

* Inside Rearview Mirror Schematics Inside Rearview Mirror Schematics

* Outside Rearview Mirror Schematics Outside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

Automatic Day-Night Mirror Description and Operation Automatic Day-Night Mirror

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, 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 inside rearview mirror face. The inside rearview mirror face should dim.

2. Engine running, place the transmission in REVERSE. The inside rearview mirror face should transition from dim to bright.

If the mirror does not transition between the bright and dim states, refer to Inside Rearview Mirror Dimming Malfunction.

3. Vehicle in PARK, shine a flashlight at the rear light sensor while observing the driver outside rearview mirror face. The outside rearview mirror face should dim.

4. Engine running, place the transmission in REVERSE. The driver outside rearview mirror face should transition from dim to bright.

If the mirror does not transition between the bright and dim states, refer to Outside Rearview Mirror Dimming Malfunction.

Circuit/System Testing

Inside Rearview Mirror Dimming Malfunction

1. Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror.

2. Wait 1 minute, test for less than 10 ohms between the ground circuit terminal 5 and ground.

If greater than the specified range, test the ground circuit for an open/high resistance.

3. Verify that a test lamp illuminates between the B+ circuit terminal 10 and ground.

If the test lamp does not illuminate test the B+ circuit for an open/high resistance or short to ground.

4. If all circuits test normal, test or replace the A10 Inside Rearview Mirror.

Outside Rearview Mirror Dimming Malfunction

1. Ignition OFF, disconnect the harness connector at the E17D Outside Rearview Mirror Glass.

2. Wait 1 minute, test for less than 10 ohms between the low reference circuit terminal 2 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 A10 inside rearview mirror.

3. Ignition ON, test for less than 1 V between the signal circuit terminal 1 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 A10 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 V between the signal circuit terminal 1 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 A10 Inside Rearview Mirror.

5. If all circuits test normal, test or replace the driver E17D Outside Rearview Mirror Glass.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Inside Rearview Mirror Replacement Inside Rearview Mirror Replacement

* Outside Rearview Mirror Glass Replacement Outside Rearview Mirror Glass Replacement