B2699

DTC B2575 or B2699

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 B2575 01
- Left Headlamp Control Circuit Short to Battery

DTC B2575 02
- Left Headlamp Control Circuit Short to Ground

DTC B2575 04
- Left Headlamp Control Circuit Open

DTC B2699 01
- Right Headlamp Control Circuit Short to Battery

DTC B2699 02
- Right Headlamp Control Circuit Short to Ground

DTC B2699 04
- Right Headlamp Control Circuit Open

Diagnostic Fault Information





Circuit/System Description

When the headlight switch is placed in low beam position, the body control module (BCM) applies a voltage to the low beam headlamps through their respective voltage supply circuits.

Conditions for Running the DTC

The headlamps are turned ON.

Conditions for Setting the DTC

B2575 01

The BCM detects a short to voltage on the left headlamp low beam control circuit.

B2575 02

The BCM detects a short to ground on the left headlamp low beam control circuit.

B2575 04

The BCM detects an open on the left headlamp low beam control circuit or an open/high resistance on the left headlamp low beam ground circuit.

B2699 01

The BCM detects a short to voltage on the right headlamp low beam control circuit.

B2699 02

The BCM detects a short to ground on the right headlamp low beam control circuit.

B2699 04

The BCM detects an open on the right headlamp low beam control circuit or an open/high resistance on the right headlamp low beam ground circuit.

Action Taken When the DTC Sets

For B2575 02, B2575 04, B2699 02 or B2699 04, the appropriate headlamp low beam will be inoperative.

For B2575 01 or B2699 01, the appropriate headlamp low beam will be continuously illuminated.

Conditions for Clearing the DTC

* The DTC will be current for as long as the fault is present.
* When the fault is no longer present, the DTC will be a history DTC.
* A history DTC will clear after 50 ignition cycles.

Reference Information
Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics (Headlights/Daytime Running Lights (DRL) Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Exterior Lighting Systems Description and Operation (Exterior 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 (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, observe the function of the E4G headlamp-left low beam and the E4F headlamp-right low beam while commanding the low beam lamps ON and OFF with a scan tool. The E4G headlamp-left low beam and the E4F headlamp-right low beam should turn ON and OFF while changing between the commanded states.

Circuit/System Testing

1. Ignition OFF, disconnect the harness X1 harness connector at the K9 BCM.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal listed below and ground:

* B+ circuit terminal 3
* B+ circuit terminal 4

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Ignition OFF, connect the harness X1 harness connector at the K9 BCM.
4. Disconnect the inline harness connector at the appropriate E4 headlamp-low beam listed below:

* E4G headlamp-left low beam X115 inline harness connector
* E4F headlamp-right low beam X116 inline harness connector

5. Connect a test lamp between the control circuit terminal G and ground.
6. Ignition ON, command the low beam lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF while 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 ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM

7. If all circuits test normal, replace the headlamp bulb or the headlamp.

Repair Instructions

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

* Headlamp Replacement (Headlamp Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming