B2545

DTC B2545

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B2545 00
- Backup Lamps Circuit

Diagnostic Fault Information






Circuit/System Description

When the PRNDL is placed in the REVERSE position, a signal is sent to the body control module (BCM). The BCM then applies voltage through the backup lamps relay control circuit energizing the backup lamps PCB relay. With the relay energized, battery voltage is applied through the left and right backup lamp fuses and the supply voltage circuits to the backup lamps.

Conditions for Running the DTC

The ignition is ON. The backup lamps must be commanded ON.

Conditions for Setting the DTC

The BCM detects a short to ground on the backup lamps relay control circuit.

Action Taken When the DTC Sets

The BCM will deactivate the backup lamps for the remainder of the ignition cycle.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.

Circuit/System Verification

Ignition ON, place the PRNDL to the REVERSE position. The backup lamps should illuminate.

Circuit/System Testing

1. Ignition OFF, disconnect the X7 harness connector at the body fuse block.
2. Connect a test lamp between the control circuit terminal 57 and ground.
3. Ignition ON, command the backup lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuit tests normal, replace the body fuse block.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Body Wiring Harness Junction Block Replacement