B2600

DTC B2600

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 B2600 01
- Left Daytime Running Lamps Control Circuit Short to Battery

DTC B2600 02
- Left Daytime Running Lamps Control Circuit Short to Ground

DTC B2600 04
- Left Daytime Running Lamps Control Circuit Open

Diagnostic Fault Information





Circuit/System Description

When the headlight switch is in the Auto position and the ambient light sensor detects sunlight, the body control module (BCM) will command the daytime running lamps to illuminate by providing 12 volts to the daytime running lamp control circuit.

Conditions for Running the DTC

* The engine is running.
* Headlamp switch in AUTO position.
* The ambient light is day.

Conditions for Setting the DTC

B2600 01

The BCM detects a short to voltage on the daytime running lamp control circuit.

B2600 02

The BCM detects a short to ground on the daytime running lamp control circuit.

B2600 04

The BCM detects an open daytime running lamp control circuit.

Action Taken When the DTC Sets

For B2600 01, the left daytime running lamp will be continuously illuminated.

For B2600 02 or B2600 04, the left daytime running lamp will be inoperative.

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, command the Left Dedicated Daytime Running Lamp ON and OFF with a scan tool. The E4C daytime running lamp - left should turn ON and OFF when changing between the commanded states.

Circuit/System Testing

1. Ignition OFF, disconnect the X1 harness connector K9 BCM.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground.

• 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 X1 harness connector at the K9 BCM.
4. Ignition OFF, disconnect the harness connector at the E4C daytime running lamp - left.
5. Test for less than 30 ohm between the ground circuit harness connector terminal G and ground.

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

6. Connect a test lamp between the control circuit terminal A and ground.
7. Ignition ON, command the Left Dedicated Daytime Running Lamp 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 an open/high resistance. If the circuit tests normal, replace the K9 BCM.

8. If all circuits test normal, replace the daytime running lamp bulb.

Repair Instructions

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

* Daytime Running Lamp Bulb Replacement (TT2) (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming