Document ID: 2830912

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach
Diagnostic Procedure Instructions provides an overview of each diagnostic category

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Ignition	1	1	—	—
Automatic Day/Night Mirror Signal	2	2	2	—
Backup Lamp Control	B2545 02	1	1	—
Automatic Day/Night Mirror Low Reference	—	2	2	—
Ground	—	1	—	—
1. Inside and Outside Rearview Mirror Automatic Dimming Malfunction 2. Outside Rearview Mirror Automatic Dimming Malfunction

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

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

Circuit/System Verification

Ignition ON.
Cover the windshield with a blanket or other suitable item.
Verify the A10 Inside Rearview Mirror face dims when shining a bright light into the rear light sensor

If the A10 Inside Rearview Mirror does not dim
Refer to Circuit/System Testing — Inside Review Mirror Dimming Inoperative

If the A10 Inside Rearview Mirror dims

Verify the A10 Inside Rearview Mirror face transitions from dim to bright while commanding the Backup Lamps Active and Inactive with a scan tool.

If the A10 Inside Rearview Mirror does not transition between dim and bright.
Refer to Circuit/System Testing — Day-Night Disable Malfunction

If the A10 Inside Rearview Mirror transitions between bright and dim states

Verify the A9A Outside Rearview Mirror-Driver face dims when shining a bright light into the rear light sensor.

If the A9A Outside Rearview Mirror-Driver does not dim
Refer to Outside Rearview Mirror Dimming Malfunction.

If the A9A Outside Rearview Mirror-Driver dims

Verify the A9A Outside Rearview Mirror-Driver face transitions from dim to bright while commanding the Backup Lamps Active and Inactive with a scan tool.

If the A9A Outside Rearview Mirror-Driver does not transition between bright and dim states
Refer to Outside Rearview Mirror Dimming Malfunction.

If the A9A Outside Rearview Mirror-Driver transitions between bright and dim states

All OK.

Circuit/System Testing

Inside Review Mirror Dimming Inoperative

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the A10 Inside Rearview Mirror. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 5 and ground.

If 10 Ω or greater

Ignition OFF, remove the test lamp.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Ignition ON.
Verify a test lamp illuminates between the ignition circuit terminal 2 and ground.

If the test lamp does not illuminate and the circuit fuse is good

Ignition OFF, remove the test lamp.
Test for less than 2 Ω in the ignition circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

Ignition OFF, remove the test lamp.
Test for infinite resistance between the ignition circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for infinite resistance between the signal circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.
If infinite resistance, replace the A10 Inside Rearview Mirror

If the test lamp illuminates

Replace the A10 Inside Rearview Mirror.

Day-Night Disable Malfunction

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror. Ignition ON
Connect a test lamp between the control circuit terminal 1 and ground
Verify the test lamp turns ON and OFF while commanding the Backup Lamps Active and Inactive with a scan tool.

If the test lamp is always OFF

Ignition OFF, remove the test lamp, disconnect the harness connector at the K9 Body Control Module.
Test for infinite resistance between the control circuit terminal 1 and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, refer to Backup Lamps Malfunction.

If the test lamp is always ON

Ignition OFF, remove the test lamp, disconnect the harness connector at the K9 Body Control Module, ignition ON.
Test for less than 1 V between the control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, refer to Backup Lamps Malfunction

If the test lamp turns ON and OFF

Replace the A10 Inside Rearview Mirror.

Outside Rearview Mirror Dimming Malfunction

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the E17D Outside Rearview Mirror Glass. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the low reference circuit terminal 2 and ground.

If 10 Ω or greater

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror.
Test for less than 2 Ω in the low reference circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace the A10 Inside Rearview Mirror.

If less than 10 Ω

Ignition ON.
Test for less than 1 V between the control circuit terminal 1 and ground.

If 1 V or greater

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror, ignition ON.
Test for less than 1 V between the control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V replace the A10 Inside Rearview Mirror.

If less than 1 V

Ignition ON, headlamps ON, transmission not in R, 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 control circuit terminal 1 and ground.

If 1 V or less

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror.
Test for infinite resistance between the control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, test or replace the A10 Inside Rearview Mirror.

If greater than 1 V

Test or replace E17 Outside Rearview Mirror Glass.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Outside Rearview Mirror Glass Replacement
Control Module References for the inside rearview mirror replacement, programming and setup

Document ID: 2222939

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach
Diagnostic Procedure Instructions provides an overview of each diagnostic category

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Ignition	1	1	—	—
Automatic Day/Night Mirror Signal	2	2	2	—
Backup Lamp Control	B2545 02	3	3	—
Automatic Day/Night Mirror Low Reference	—	2	2	—
Ground	—	1	—	—
1. Inside and Outside Rearview Mirror Automatic Dimming Malfunction 2. Outside Rearview Mirror Automatic Dimming Malfunction 3. Mirror Automatic Day-Night Disable Feature Malfunction

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, backup lamp control voltage is supplied as an input to the inside rearview mirror. The mirror monitors this input to disable the automatic day-night feature. This allows the driver to see objects in the mirror clearly when backing up, regardless of the rear light sensor status.

Reference Information

Schematic Reference

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

Circuit/System Verification

Engine running, headlamps ON.
Cover the windshield with a blanket or other suitable item.
Verify the A10 Inside Rearview Mirror face dims when shining a bright light into the rear light sensor

If the A10 Inside Rearview Mirror does not dim
Refer to Circuit/System Testing — Inside Review Mirror Dimming Inoperative

If the A10 Inside Rearview Mirror dims

Park brake applied, verify the A10 Inside Rearview Mirror face transitions from dim to bright when placing the transmission selector in R (reverse).

If the A10 Inside Rearview Mirror does not transition between dim and bright.
Refer to Circuit/System Testing — Day-Night Disable Malfunction

If the A10 Inside Rearview Mirror transitions between bright and dim states

Vehicle in PARK, shine a flashlight at the rear light sensor while observing the A9A Outside Rearview Mirror-Driver face.
Verify the A9A Outside Rearview Mirror-Driver face dims.

If the A9A Outside Rearview Mirror-Driver does not dim
Refer to Outside Rearview Mirror Dimming Malfunction.

If the A9A Outside Rearview Mirror-Driver dims

Engine running, park brake applied, place the transmission in REVERSE.
Verify the A9A Outside Rearview Mirror-Driver face transitions from dim to bright.

If the A9A Outside Rearview Mirror-Driver does not transition between bright and dim states
Refer to Outside Rearview Mirror Dimming Malfunction.

If the A9A Outside Rearview Mirror-Driver transitions between bright and dim states

All OK.

Circuit/System Testing

Inside Review Mirror Dimming Inoperative

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the A10 Inside Rearview Mirror. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 5 and ground.

If 10 Ω or greater

Ignition OFF, remove the test lamp.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Ignition ON.
Verify a test lamp illuminates between the ignition circuit terminal 2 and ground.

If the test lamp does not illuminate and the circuit fuse is good

Ignition OFF, remove the test lamp.
Test for less than 2 Ω in the ignition circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

Ignition OFF, remove the test lamp.
Test for infinite resistance between the ignition circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for infinite resistance between the signal circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.
If infinite resistance, replace the A10 Inside Rearview Mirror

If the test lamp illuminates

Replace the A10 Inside Rearview Mirror.

Day-Night Disable Malfunction

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror.
Connect a test lamp between the signal circuit terminal 1 and ground
Ignition ON, verify the test lamp turns ON and OFF while commanding the Backup Lamps Active and Inactive with a scan tool.

If the test lamp is always OFF

Ignition OFF, remove the test lamp, disconnect the X204 inline harness connector.
Test for infinite resistance between the signal circuit terminal 1 and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, refer to Backup Lamps Malfunction.

If the test lamp is always ON

Ignition OFF, remove the test lamp, disconnect the X204 inline harness connector, ignition ON.
Test for less than 1 V between the signal circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, refer to Backup Lamps Malfunction

If the test lamp turns ON and OFF

Replace the A10 Inside Rearview Mirror.

Outside Rearview Mirror Dimming Malfunction

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the A9A Outside Rearview Mirror-Driver. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the low reference circuit terminal 2 and ground.

If 10 Ω or greater

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror.
Test for less than 2 Ω in the low reference circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace the A10 Inside Rearview Mirror.

If less than 10 Ω

Ignition ON.
Test for less than 1 V between the control circuit terminal 1 and ground.

If 1 V or greater

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror, ignition ON.
Test for less than 1 V between the control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V replace the A10 Inside Rearview Mirror.

If less than 1 V

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.
Test for greater than 1 V between the control circuit terminal 1 and ground.

If 1 V or less

Ignition OFF, disconnect the harness connector at the A10 Inside Rearview Mirror, ignition ON.
Test for infinite resistance between the control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, test or replace the A10 Inside Rearview Mirror.

If greater than 1 V

Test or replace A9A Outside Rearview Mirror-Driver.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Document ID: 2220049

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Left Heated Mirror Element Control	2	1	3	—
Driver Outside Rearview Mirror Ground	—	1	—	—
Right Heated Mirror Element Control	2	1	3	—
Passenger Outside Rearview Mirror Ground	—	1	—	—
1. Single Heated Mirror Inoperative 2. Both Heated Mirrors Inoperative 3. Heated Mirrors Always On

Circuit/System Description

The RR DEFOG relay supplies voltage to the outside rearview mirror heater elements based on the current state of the rear window defogger. The relay supplies B+ through the driver/passenger mirror heating element control circuits when a request is seen.

Reference Information

Schematic Reference

Outside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Outside Mirror Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

Engine running.
Verify the E18 Rear Defogger Grid turns ON and OFF when commanding the Rear Defogger On and Off with a scan tool.

If the E18 Rear Defogger Grid does not turn ON or OFF
Refer to Rear Window Defogger Malfunction.

If the E18 Rear Defogger Grid turns ON and OFF

Verify the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm when commanding the Rear Defogger On with a scan tool.

If the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger do not become warm
Refer to Circuit/System Testing.

If the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm

All OK.

Circuit/System Testing

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate E17 Outside Rearview Mirror Glass. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal listed below and ground.

E17D Outside Rearview Mirror Glass-Driver ground circuit terminal 4
E17P Outside Rearview Mirror Glass-Passenger ground circuit terminal 2

If 10 Ω or greater

Ignition OFF.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Ignition ON, connect a test lamp between the control circuit terminal and the ground circuit terminal listed below:

E17D Outside Rearview Mirror Glass-Driver control circuit terminal 3 and ground circuit terminal 4
E17P Outside Rearview Mirror Glass-Passenger control circuit terminal 1 and ground circuit terminal 2

Verify the test lamp turns ON and OFF when commanding the Rear Defogger On and Off with a scan tool.

If the test lamp is always OFF

Ignition OFF, remove the test lamp, disconnect the harness connector at the X50A Fuse Block-Underhood.
Test for infinite resistance between the control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace the E17 Outside Rearview Mirror Glass.

If the test lamp is always ON

Ignition OFF, remove the test lamp, disconnect the harness connector at the X50A Fuse Block-Underhood, ignition ON.
Test for less than 1 V between the control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, replace the X50A Fuse Block-Underhood

If the test lamp turns ON and OFF

Test or replace the E17 Outside Rearview Mirror Glass.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Outside Rearview Mirror Glass Replacement

Accessory Wiring Junction Block Replacement

Document ID: 2381498

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Outside Rearview Mirror Switch B+	1	1	—	—
Driver Left/Right Mirror Horizontal Motor Control	1	2	2	—
Driver Left/Right Mirror Vertical Motor Control	1	2	2	—
Passenger Left/Right Mirror Horizontal Motor Control	1	3	3	—
Passenger Left/Right Mirror Vertical Motor Control	1	3	3	—
Outside Rearview Mirror Switch Ground	—	1	—	—
1. Both Outside Power Mirrors Inoperative 2. Driver Outside Power Mirror Malfunction 3. Passenger Outside Power Mirror Malfunction

Circuit/System Description

The outside rearview mirror switch controls the functions of the outside rearview mirrors based on the position of the mirror selector switch and which movement position is selected. The outside rearview mirror switch has four positions: up, down, left, and right. B+ is applied to the switch and when a movement position switch is selected, B+ is sent to the mirror via a motor control circuit. The opposite motor control circuit acts as a ground circuit for the bi-directional mirror motor.

Reference Information

Schematic Reference

Outside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Outside Mirror Description and Operation

Electrical Information Reference

Circuit/System Verification

Verify the A9A Outside Rearview Mirror-Driver and the A9B Outside Rearview Mirror-Passenger operates UP, DOWN, LEFT and RIGHT with the S52 Outside Rearview Mirror Switch.

If both the A9A Outside Rearview Mirror-Driver and the A9B Outside Rearview Mirror-Passenger do not move
Refer to Circuit/System Testing — Both Outside Mirrors Inoperative.

If only the A9A Outside Rearview Mirror-Driver or the A9B Outside Rearview Mirror-Passenger does not move UP, DOWN, LEFT or RIGHT
Refer to Circuit/System Testing — Single Outside Mirror Malfunction.

If both the A9A Outside Rearview Mirror-Driver and the A9B Outside Rearview Mirror-Passenger move UP, DOWN, LEFT and RIGHT

All OK.

Circuit/System Testing

Both Outside Mirrors Inoperative

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S52 Outside Rearview Mirror Switch. It may take up to 2 minutes for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 2 and ground.

If 10 Ω or greater

Ignition OFF.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Verify a test lamp illuminates between the B+ circuit terminal 1 and ground.

If the test lamp does not illuminate and the circuit fuse is good

Ignition OFF.
Test for less than 2 Ω in the B+ circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

Ignition OFF.
Test for infinite resistance between the B+ circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for infinite resistance between each of the control circuit terminals listed below and ground:

Terminal 3 control circuit
Terminal 4 control circuit
Terminal 5 control circuit
Terminal 7 control circuit
Terminal 8 control circuit

If less than infinite resistance, repair the short to ground on the circuit.
If infinite resistance, test or replace the appropriate M77 Outside Rearview Mirror Motor.

If the test lamp illuminates

Test or replace the S52 Outside Rearview Mirror Switch.

Single Outside Mirror Malfunction

Ignition OFF, disconnect the harness connector at the appropriate A9 Outside Rearview Mirror. Ignition ON
Connect a test lamp between the control circuit terminal 3 and the control circuit terminal 2.
Verify the test lamp illuminates when commanding the UP and DOWN functions with the S52 Outside Rearview Mirror Switch.

If the test lamp does not illuminate during either of the UP and DOWN commands

Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch.
Test for infinite resistance between each control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in each control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace at the S52 Outside Rearview Mirror Switch.

If the test lamp is always ON

Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch, ignition ON.
Test for less than 1 V between each control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, replace the S52 Outside Rearview Mirror Switch

If the test lamp illuminates during UP and DOWN the commands

Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 2.
Verify the test lamp illuminates when commanding the LEFT and RIGHT functions with the S52 Outside Rearview Mirror Switch.

If the test lamp does not illuminate during either of the LEFT and RIGHT commands

Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch.
Test for infinite resistance between each control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in each control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, replace at the S52 Outside Rearview Mirror Switch.

If the test lamp is always ON

Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch, ignition ON.
Test for less than 1 V between each control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, replace the S52 Outside Rearview Mirror Switch

If the test lamp illuminates during the LEFT and RIGHT commands

Test or replace the M77 Outside Rearview Mirror Motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Document ID: 2380895

Note: The following steps must be completed before using the symptom tables.

Perform the Diagnostic System Check - Vehicle before using the Symptom Tables in order to verify that all of the following are true:

There are no DTCs set.
The control modules can communicate via the serial data link.

Review the system operation in order to familiarize yourself with the system functions. Refer to the following system descriptions:

Visual/Physical Inspection

Inspect for aftermarket devices which could affect the operation of the system.
Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

Mirrors

Related components