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 driver circuit to the Back up lamp ground located in the inside rearview mirror. The Back up lamps are also directly grounded through G401.

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 lamp control circuit when the backup lamps are being commanded ON.

ACTION TAKEN WHEN THE DTC SETS
The backup lamps do not illuminate.

CONDITIONS FOR CLEARING THE DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction-free ignition cycles.
- The BCM receives the clear code command from the scan tool.

CIRCUIT/SYSTEM VERIFICATION
Ignition ON, activate the Backup Lamps output control on the scan tool. The Backup Lamps parameter in the data list should display On and the backup lamps should illuminate.

CIRCUIT/SYSTEM TESTING
1. Ignition OFF, disconnect the instrument panel (I/P) fuse block connector X1 34, inside rearview mirror.
2. Ignition OFF, disconnect the BCM harness connector X6 and test for a ground signal at the connector terminal 2.
- If the circuit exhibits a ground signal, repair the short to ground in the control circuit.
3. Reconnect the inside rearview mirror and test the BCM harness connector X1, terminal 34 again for ground.
- If the circuit now exhibits a ground signal of 20 ohms or less, replace the inside rearview mirror.
4. Reconnect the I/P fuse block connector and test the BCM harness connector X1, terminal 34 again for ground.
- If the circuit now exhibits a ground signal of 20 ohms or less, replace the I/P fuse block.
- If the circuit does not exhibit a ground, replace the BCM.

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
- Programming and Relearning Programming and Relearning
- Instrument Panel Electrical Center or Junction Block Replacement
- Rearview Mirror Replacement