Chevrolet Trax: 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

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 seen.

Reference Information

Schematic Reference

• Outside Rearview Mirror Schematics (Encore), Outside Rearview Mirror Schematics (Trax)
• Defogger Schematics (Encore) , Defogger Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

• Outside Mirror Description and Operation (DG6/DL6 or DI7), Outside Mirror Description and Operation (AAG)
• Rear Window Defogger 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. 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 or OFF

Refer to Rear Window Defogger Malfunction .

• 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 or E17P Outside Rearview Mirror Glass- Passenger do not become warm

Refer to Circuit/System Testing - Single Outside Mirror Defogger Inoperative.

• If both E17D Outside Rearview Mirror Glass-Driver and E17P Outside Rearview Mirror Glass-Passenger never become warm or are always warm

Refer to Circuit/System Testing - Both Outside Mirror Defogger Malfunction.

• If both the E17D Outside Rearview Mirror Glass-Driver and the E17P Outside Rearview Mirror Glass-Passenger become warm

4. All OK.

Circuit/System Testing

Single Outside Mirror Defogger Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the 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 ohms between the ground circuit terminal 5 and ground.

• If 10 ohms or greater

1. Ignition OFF.
2. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 10 ohms

3. Engine running, connect a test lamp between the control circuit terminal 4 and the ground circuit terminal 5.
4. Verify the test lamp turns ON when commanding the Rear Defogger On with a scan tool

• If the test lamp is always OFF

1. Ignition OFF, remove the test lamp, disconnect the X2 harness connector at the X50A Fuse Block- Underhood.
2. Test for less than 2 ohms in the control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the X50A Fuse Block-Underhood.
• If the test lamp turns ON

5. Test or replace the E17 Outside Rearview Mirror Glass.

Both Outside Mirror Defogger Malfunction

1. Connect a test lamp between the control circuit terminal 8 and ground.
2. Engine running.
3. 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, remove the test lamp, 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, remove the test lamp, disconnect the X2 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.
• If infinite resistance, refer to Rear Window Defogger Malfunction
• If the lamp turns on and off

4. Replace the E17 Outside Rearview Mirror Glass.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Outside Rearview Mirror Glass Replacement
• Front Compartment Fuse Block Replacement

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