GM Service Manual Online
For 1990-2009 cars only

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/Right Mirror Motor Horizontal Control

1

1

--

--

Left/Right Mirror Motor Vertical Control

1

1

--

--

Left/Right Mirror Motor Common Control

1

1

--

--

1. Power mirror malfunction

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. B+ is applied to the switch from the power mirror fuse and when a movement position switch is selected, voltage is sent to the commanded mirror via a mirror control circuit. 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

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

  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 A9A driver outside rearview 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 A9B passenger outside rearview mirror should move in the commanded direction.

Circuit/System Testing

  1. Ignition OFF, disconnect the X1 harness connector at the S52 outside mirror switch.
  2. Wait 1 minute, test for less than 10 Ω between the ground circuit terminal 5 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Ignition OFF, connect the harness connector at the S52 outside mirror switch.
  7. Disconnect the harness connector at the appropriate A9 outside rearview mirror.
  8. Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 2.
  9. Operate the vertical switch UP and DOWN. The test lamp should turn ON when commanding the UP and DOWN states.
  10. 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 the control circuits. If the circuits test normal, replace the S52 outside mirror switch.
  11. Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 3.
  12. Operate the horizontal switch LEFT and RIGHT. The test lamp should turn ON when commanding the LEFT and RIGHT states.
  13. 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 the control circuits. If the circuits test normal, replace the S52 outside mirror switch.
  14. If all circuits test normal, test or replace the A9 outside rearview mirror.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Outside Rearview Mirror Replacement
    •  Outside Remote Control Rearview Mirror Switch Replacement