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.

### DTC Descriptor

DTC B1544 01: Mirror Motors Common Circuit Short to Battery
DTC B1544 02: Mirror Motors Common Circuit Short to Ground
DTC B1544 04: Mirror Motors Common Circuit Open
DTC B1600 01: Mirror Motor Vertical Circuit Short to Battery
DTC B1600 02: Mirror Motor Vertical Circuit Short to Ground
DTC B1600 04: Mirror Motor Vertical Circuit Open
DTC B1605 01: Mirror Motor Horizontal Circuit Short to Battery
DTC B1605 02: Mirror Motor Horizontal Circuit Short to Ground
DTC B1605 04: Mirror Motor Horizontal Circuit Open

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Left/Right Mirror Motor Horizontal Control | B1544 04, B1605 02 | B1544 04, B1605 04 | B1605 01 | --
Left/Right Mirror Motor Common Control | B1544 04, B1600 04, B1605 04, B1544 02 | B1544 04, B1600 04, B1605 04 | B1544 01 | --
Left/Right Mirror Motor Vertical Control | B1544 04, B1600 02 | B1544 04, B1600 04 | B1600 01 | --

### Circuit/System Description

The Driver Door Switch (DDS) or Passenger Door Switch (PDS) controls the mirror horizontal and vertical motors through the use of bi-directional motor controls. When the mirror is commanded up and down, voltage or ground is supplied to the mirror vertical motor through the mirror motor up/down control circuit and voltage or ground is supplied through the mirror motor common circuit.

Horizontal controls operate in the same manner with the mirror motor left/right control circuit supplying voltage or ground and the mirror motor common circuit suppling voltage or ground to the mirror horizontal motor when the mirror is commanded right and left.

### Conditions for Running the DTC

The power mirror is being commanded left, right, up, or down.

### Conditions for Setting the DTC

#### B1544

An improper voltage level is detected on the mirror motor common control circuit.

#### B1600

An improper voltage level is detected on the mirror motor up/down control circuit.

#### B1605

An improper voltage level is detected on the mirror motor left/right control circuit.

### Action Taken When the DTC Sets

Operation of the affected motor is suspended as long as the fault is present.

### Conditions for Clearing the DTC

• | A current DTC will clear when the fault is no longer present.

• | A history DTC will clear after 40 malfunction-free ignition cycles.

### 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 Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Command the left and right outside mirror to move up, down, left and right using the mirror directional switch. The mirror should move in the commanded direction.

### Circuit/System Testing

1. Ignition OFF, disconnect the X1 (RPO DS3) or X2 (RPO W49) harness connector at the outside rearview mirror.
2. Connect a test lamp between the control circuit terminal 2 and the control circuit terminal 6.
3. Ignition ON, commanded the mirror left and right using the mirror directional switch. The test lamp should turn ON and OFF as the mirror commanded to the left and right.

⇒ | If the test lamp is always ON, test the control circuits for a short to voltage. If the circuit tests normal, replace the appropriate door switch.

⇒ | If the test lamp is always OFF, test the control circuits for a short to ground or an open/high resistance. If the circuit tests normal, replace the appropriate door switch.

4. Ignition OFF, install a test lamp between the control circuit terminal 1 and the control circuit terminal 6.
5. Ignition ON, commanded the mirror up and down using the mirror directional switch. The test lamp should turn ON and OFF as the mirror commanded up and down.

⇒ | If the test lamp is always ON, test the control circuits for a short to voltage. If the circuit tests normal, replace the appropriate door switch.

⇒ | If the test lamp is always OFF, test the control circuits for a short to ground or an open/high resistance. If the circuit tests normal, replace the appropriate door switch.

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

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Outside Rearview Mirror Motor Replacement

• | Control Module References for DDS or PDS replacement, setup, and programming