Service Information

Captiva

DTC B2575

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

DTC B2575 00: Headlamp Control Circuit

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Headlamp Dipped beam Relay Control Circuit	B2575 00	B2575 00	B2575 00	-
Headlamp Dipped beam Relay Battery Supply Voltage Circuit	B2575 00	B2575 00	--	--

The dipped beam headlamps are controlled by the body control module (BCM). The BCM grounds the headlamp dipped beam relay control circuit in order to energise the DIPPED BEAM relay coil. The DIPPED BEAM relay then sends voltage to the dipped beam headlamps.

Conditions for Running the DTCs

•	The headlamps are commanded ON.

•	Headlamp dimmer switch must be in the dipped beam position.

Conditions for Setting the DTC

One or more of the following conditions are present:

•	The headlamp dipped beam relay control circuit is open, shorted to ground, or shorted to voltage.

•	The headlamp dipped beam relay battery supply voltage circuit is open or shorted to ground.

Action Taken When the DTC Sets

The BCM turns OFF the headlamp dipped beam relay control for the remainder of the ignition cycle.

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.

Reference Information

Schematic Reference

Headlamps/Daytime Running Lamps (DRL) Schematics

Connector End View Reference

Component Connector End Views

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 Verification

Ignition ON, activate the Dipped beam output control on the scan tool. The Dipped beam Relay Command parameter in the data list should display On and the dipped beam headlamps should illuminate.

Circuit/System Testing

Ignition OFF, disconnect the underbonnet fuse block connector C4 and test for a short to voltage, short to ground, an open, or high resistance at the connector terminal K2.
Activate the headlamp switch, place the headlamp dimmer switch in the dipped beam position, and test for a ground signal at the underbonnet fuse block connector C4 terminal K2.

⇒	If a ground signal is present, replace the underbonnet fuse block. If a ground signal is not present, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming