B2570

DTC B2570

Diagnostic Instructions

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

DTC Descriptor
DTC B2570 02
- Cargo Lamp Control Circuit Short to Ground

Diagnostic Fault Information






Circuit/System Description

When the body control module (BCM) receives a liftgate open signal, the BCM supplies B+ to the cargo lamp control circuit. This will illuminate the rear compartment lamp.

Conditions for Running the DTC

The liftgate is in open position.

Conditions for Setting the DTC

The BCM detects a short to ground on the cargo lamp control circuits.

Action Taken When the DTC Sets

The rear compartment lamp is OFF.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists.

Reference Information
Schematic Reference

Interior Lights Schematics Interior Lights Schematics
Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation

Interior Lighting Systems Description and Operation Interior Lighting Systems
Electrical Information Reference

* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

Command the Cargo Lamp Duty Cycle test ON and OFF with a scan tool. The rear compartment lamps should be ON and OFF.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the E33 Cargo Lamp.
2. Test for less than 5 ohm between the ground circuit terminal 2 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal 1 and ground.
4. Command the Cargo Lamp Duty Cycle test 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 K9 BCM.
• If the test lamp is always OFF, test the control circuit for a short to round or open/high resistance. If the circuit tests normal, replace the K9 BCM.

5. If all circuits test normal, replace the E33 Cargo Lamp.

Repair Instructions

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

* Rear Compartment Courtesy Lamp Replacement Rear Compartment Courtesy Lamp Replacement
* Control Module References Control Module References for BCM control module replacement setup and programming