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 Descriptors
DTC B2575 01
- Headlamps Control Circuit Short to Battery

DTC B2575 02
- Headlamps Control Circuit Short to Ground

DTC B2575 04
- Headlamps 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

With the headlamp switch in the ON position, the headlamp switch headlamp ON signal circuit is grounded through the headlamp and panel dimmer switch. The body control module (BCM) responds by applying a pulse width modulated (PWM) voltage to the left and right low beam headlamp control circuits illuminating the low beam headlamps.

Conditions for Running the DTC

* Battery voltage must be between 9-16 V.
* Low beam headlamps ON.

Conditions for Setting the DTC

B2575 01

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

B2575 02

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

B2575 04

The BCM detects an open in the left headlamp low beam control circuit.

B2699 01

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

B2699 02

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

B2699 04

The BCM detects an open in the right headlamp low beam control circuit.

Actions Taken When the DTC Sets

When DTC B2575 or B2699 is present, the associated low beam headlamp 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

Headlights Schematics (Headlights 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 Testing

1. Ignition OFF, disconnect the harness connector at the appropriate T7 or E13 headlamp assembly.
2. Ignition OFF, wait one minute, then test for less than 5 ohm between the ground circuit terminal listed below and ground:

* T7 headlamps - terminal A
* E13 headlamps - terminal 2

• 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 Low Beam Lamp Command 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 ground or open/high resistance. If the circuit tests normal, replace the K9 BCM.

5. If all circuits test normal, test or replace the T7 or E13 headlamp assembly.

Repair Instructions

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

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