Chevrolet Trax: Backup lamps malfunction (automatic transmission)
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
With the engine running and the transmission in the reverse position, the
transmission control module (TCM)
sends a serial data message to the body control module (BCM). The message
indicates that the gear selector is
in the reverse position. The BCM applies battery voltage to the backup lamps
control circuit illuminating the
backup lamps. Once the driver moves the gear selector out of the reverse
position, a message is sent by the
TCM via serial data requesting the BCM to remove battery voltage from the backup
lamps control circuit. The
engine must be running for the backup lamps to operate.
Diagnostic Aids
When testing at the backup lamp bulb socket, make sure all measurements and
test lamp connections are in the
correct terminal location and do not come in contact with each other during
testing.
Reference Information
Schematic Reference
- Exterior Lights Schematics (Encore) , Exterior Lights Schematics (Trax)
- Body Control System Schematics (Encore) , Body Control System
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
Exterior Lighting Systems 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 Testing
- Ignition OFF, exterior lamps OFF, rear hatch latch latched, remove the
appropriate E5 Backup Lamp bulb
at the appropriate E42 Tail Lamp Assembly.
- Test for less than 5 ohms between the ground circuit at the socket
terminal and ground.
- Ignition OFF.
- 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 5 ohms
- Connect a test lamp between the control circuit at the socket terminal
and ground, ignition ON.
- Verify the test lamp turns ON and OFF when commanding the Backup Lamps
ON and OFF with a scan
tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X7 harness connector at the K9 Body Control
Module.
- 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
- 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 K9 Body Control Module.
- If the test lamp is always ON
- Ignition OFF, disconnect the X7 harness connector at the K9 Body Control
Module, ignition ON.
- Test for less than 1 V between the control circuit terminal and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K9 Body Control Module.
- If the test lamp turns ON and OFF
- Test or replace the appropriate E5 Backup Lamp.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Backup Lamp Bulb Replacement (Trax) , Backup Lamp Bulb Replacement (Encore)
- Control Module References for BCM replacement, programming, and setup
READ NEXT:
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.
Diag
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.
Diag
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.
Diag
SEE MORE:
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
DT
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
DT