2010 Cadillac CTS Sedan AWD V6-3.6L Page 502
and inside rearview mirror. 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 lamp control circuit. The engine may need to be running for the backup lamps to
function.
Conditions for Running the DTC
Battery voltage must be between 9-16 V.
Conditions for Setting the DTC
DTC B2545 00 will set when one of the following conditions exists:
* The BCM detects a short to ground in the backup lamps control circuit.
* The BCM detects a short to ground or an open/high resistance in the BCM 4 fuse B+ circuit.
Actions Taken When the DTC Sets
The backup lamps will not operate.
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.
Reference Information
Schematic Reference
Exterior Lights Schematics (See: Diagrams/Electrical Diagrams/Lighting and Horns/System Diagram/Exterior Lights Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description
and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
2. Connect a test lamp between the control circuit terminal 9 and ground.
3. 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.
瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
瀚慖f 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, test the
BCM 4 fuse B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
4. Connect the harness connector at the inside rearview mirror.
5. Ignition OFF, disconnect the harness connector at the appropriate tail lamp.
6. Ignition OFF, exterior lamps OFF, test for less than 5.0 ohm between the ground circuit terminal C and ground.
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
7. Connect a test lamp between the control circuit terminal E and ground.
8. 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.
瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
瀚慖f 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
