Buick Regal: Symptoms - Mirrors

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

1. 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.

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

• Outside Mirror Description and Operation (With A45)Outside Mirror Description and Operation (Without A45)
• Automatic Day-Night Mirror Description and Operation

Visual/Physical Inspection

• Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories.
• 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:

• Heated Mirrors Malfunction
• Automatic Day-Night Mirrors Malfunction
• Power Mirror Malfunction (With A45)Power Mirror Malfunction (Without A45)

HEATED MIRRORS MALFUNCTION

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

1. Heated Mirror Inoperative
2. Heated Mirror Always On

Circuit/System Description

The rear defogger 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 circuit when a request is received.

Reference Information

Schematic Reference

Outside Rearview Mirror Wiring Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Outside Mirror Description and Operation (With A45)Outside Mirror Description and Operation (Without A45)

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. Engine running.

2. 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 and OFF

Refer to Rear Window Defogger Malfunction.

• Go to next step: If the E18 Rear Defogger Grid turns ON and OFF

3. 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.

• Go to next step: If both E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm

4. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 and X2 harness connector at the appropriate E17 Outside Rearview Mirror Glass. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 10 Ω between the ground circuit terminal A X2 and ground.

• If 10 Ω or greater

1. Ignition OFF.
2. 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.

• Go to next step: If less than 10 Ω

3. Connect a test lamp between the control circuit terminal A X1 and ground.

4. Engine running.

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

• If the lamp is always ON

1. Ignition OFF, disconnect the X2 harness connector at X50A Fuse Block - Underhood, ignition ON.
2. 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 Rear Window Defogger Malfunction.

• If the lamp is always OFF

1. Ignition OFF, disconnect the harness connector at X50A Fuse Block - Underhood, ignition ON.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. 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 Rear Window Defogger Malfunction.

• Go to next step: If the lamp turns on and off

6. Replace the E17 Outside Rearview Mirror Glass.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Outside Rearview Mirror Glass Replacement.

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