For 1990-2009 cars

### 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 Voltage | 1 | 1 | -- | --
Mirror Motor Right Control | 3 | 3 | 3 | --
Mirror Motor Left Control | 2, 3 | 2, 3 | 2, 3 | --
Mirror Motor Up Control | 2 | 2 | 2 | --
Ground | 1 | 1 | -- | --
1. All power mirror functions inoperative 2. Mirror vertical controls inoperative 3. Mirror horizontal controls inoperative

### Circuit/System Description

The outside rearview mirror switch controls 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. Ignition voltage is applied to the switch via the body control module (BCM) and when a movement position switch is selected, voltage is sent to the commanded mirror via a mirror control control. The opposite mirror control circuit acts as a ground circuit for the bi-directional mirror motor. Ground is the applied through the switch.

### Reference Information

#### Schematic Reference

Outside Rearview Mirror Schematics

#### Connector End View Reference

Mirror Connector End Views

#### Description and Operation

Outside Mirror Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Circuit/System Verification

1. Ignition ON, with the mirror selector switch in the DRIVER position, command the mirrors UP, DOWN, LEFT, and RIGHT using the mirror directional switch. The driver mirror should move in the commanded direction.
2. With the mirror selector switch in the PASSENGER position, command the mirrors UP, DOWN, LEFT, and RIGHT using the mirror directional switch. The passenger mirror should move in the commanded direction.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the outside rearview mirror switch.
2. Ignition OFF, test for less than 2 ohms of resistance between the ground circuit terminal 2 and ground.

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

3. Ignition ON, verify a test lamp illuminates between the ignition voltage circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Ignition OFF, reconnect the harness connector at the outside rearview mirror switch. Disconnect the harness connector at the inoperative mirror.
5. Ignition OFF, with the outside rearview mirror switch in the UP position, test for 5 ohms of resistance between the control circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

6. With the outside rearview mirror switch in the DOWN position, test for 5 ohms of resistance between the control circuit terminal 4 and ground.

⇒ | If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

7. With the outside rearview mirror switch in the LEFT position, test for 5 ohms of resistance between the control circuit terminal 1 and ground.

⇒ | If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

8. With the outside rearview mirror switch in the RIGHT position, test for 5 ohms of resistance between the control circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

9. Ignition ON, with the outside rearview mirror switch in the UP position, verify a test lamp illuminates between the control circuit terminal 4 and ground.

⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

10. Ignition ON, with the outside rearview mirror switch in the DOWN position, verify a test lamp illuminates between the control circuit terminal 2 and ground.

⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

11. Ignition ON, with the outside rearview mirror switch in the LEFT position, verify a test lamp illuminates between the control circuit terminal 2 and ground.

⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

12. Ignition ON, with the outside rearview mirror switch in the RIGHT position, verify a test lamp illuminates between the control circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the outside rearview mirror switch.

13. If all circuits test normal, test or replace the applicable outside rearview mirror motor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Outside Rearview Mirror Replacement

• | Control Module References for BCM replacement, setup, and programming