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 Descriptors
DTC B1544 01: Mirror Motors Common Circuit Short to BatteryDTC 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 Horizontal Motor Control | B1544 04, B1605 02 | B1544 04, B1605 04 | B1605 01 | -- |
Left/Right Mirror Vertical Motor Control | B1544 04, B1600 02 | B1544 04, B1600 04 | B1600 01 | -- |
Left/Right Mirror Motor Common Control | B1544 04, B1600 04, B1605 04, B1544 02 | B1544 04, B1600 04, B1605 04 | B1544 01 | -- |
Circuit/System Description
The driver door module (DDM) and passenger door module (PDM) each provide motor control output functions for their respective mirrors. These output controls allow each door module to command their respective power mirrors in horizontal and vertical positions. The power mirror switch is integrated into the DDM. When the power mirror switch is activated to the up, down, left or right positions, the DDM responds by commanding the driver mirror to the desired position. The DDM also sends a GMLAN serial data message to the PDM to command the passenger mirror to the appropriate position. Each door module commands their respective mirror motors by applying a ground or voltage to the control circuit, depending on the desired mirror position.
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
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 vertical control circuit.
B1605
An improper voltage level is detected on the mirror motor horizontal control circuit.
Actions Taken When the DTC Sets
| • | When DTC B1544 is present, all mirror controls will be disabled. |
| • | When DTC B1600 is present, the vertical mirror control will be disabled. |
| • | When DTC B1605 is present, the horizontal mirror control will be disabled. |
Conditions for Clearing the DTC
| • | A current DTC will clear when the fault is no longer present |
| • | A history DTC will clear after 40 fault free ignition cycles |
Reference Information
Schematic Reference
Outside Rearview Mirror Schematics
Connector End View Reference
Description and Operation
Outside Mirror Description and Operation
Electrical Information Reference
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
Driver
- Ignition OFF, disconnect the X2 harness connector at the outside rearview mirror.
- Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 2.
- Command the mirror UP and DOWN with a scan tool. The test lamp should turn ON when commanding the UP and DOWN states.
- Connect a test lamp between the control circuit terminal 3 and the control circuit terminal 2.
- Command the mirror LEFT and RIGHT with a scan tool. The test lamp should turn ON when commanding the LEFT and RIGHT states.
- If all circuits test normal, test or replace the outside rearview mirror.
| ⇒ | If the test lamp remains OFF during either of the commands, test for a short to voltage, short to ground, or an open/high resistance on either control circuit. If the circuits test normal, replace the DDM. |
| ⇒ | If the test lamp remains OFF during either of the commands, test for a short to voltage, short to ground, or an open/high resistance on either control circuit. If the circuits test normal, replace the DDM. |
Passenger
- Ignition OFF, disconnect the harness connector at the outside rearview mirror.
- Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 2.
- Command the mirror UP and DOWN with a scan tool. The test lamp should turn ON when commanding the Up and DOWN states.
- Connect a test lamp between the control circuit terminal 3 and the control circuit terminal 2.
- Command the mirror LEFT and RIGHT with a scan tool. The test lamp should turn ON when commanding the LEFT and RIGHT states.
- If all circuits test normal, test or replace the outside rearview mirror.
| ⇒ | If the test lamp remains OFF during either of the commands, test for a short to voltage, short to ground, or an open/high resistance on either control circuit. If the circuits test normal, replace the PDM. |
| ⇒ | If the test lamp remains OFF during either of the commands, test for a short to voltage, short to ground, or an open/high resistance on either control circuit. If the circuits test normal, replace the PDM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for DDM or PDM replacement, setup, and programming |
