B2610

DTC B2610

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 B2610 00
- Passenger Compartment Dimming 1 Circuit

DTC B2610 01
- Passenger Compartment Dimming 1 Circuit Short to Battery

DTC B2610 02
- Passenger Compartment Dimming 1 Circuit Short to Ground

DTC B2610 04
- Passenger Compartment Dimming 1 Circuit Open




Diagnostic Fault Information






Circuit/System Description

When the instrument panel lamps dimmer switch is activated, a variable voltage signal is applied through the LED dimmer switch signal circuit to the body control module (BCM). The BCM then applies a message on the low speed GMLAN serial data communication circuit to the door switches to illuminate the switch backlighting. The BCM, driver door switch, and passenger door switch then applies a variable voltage signal through the LED dimming supply circuit to the components on that circuit.


Conditions for Running the DTC

The ignition is ON.


Conditions for Setting the DTC

The BCM, driver door switch, and passenger door switch detects a short to voltage, short to ground, or an open on the LED dimming supply circuit.


Action Taken When the DTC Sets

The BCM, driver door switch, and passenger door switch will cease attempts to dim or illuminate the LED lamps.


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

Interior Lights Dimming Schematics (Interior Lights Dimming Schematics)
Connector End View Reference

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

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

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Programming and Relearning (Programming and Relearning)for Scan Tool Information


Circuit/System Verification

Ignition and park lamps ON, vary the interior lamp dimming switch from dim to full bright. The LED lamps should dim and then become full bright.


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the affected component.
2. Ignition OFF, verify that a test lamp illuminates between the listed ground circuit terminal and battery voltage.

* Left steering wheel switch terminal 8
* Right steering wheel switch terminal 1
* Windshield wiper/washer switch terminal 1
* Analog clock terminal 2
* DIC switch terminal 5


• If the test lamp does not illuminate, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the listed LED dimming control circuit terminal and ground.

* Left steering wheel switch terminal 6
* Right steering wheel switch terminal 2
* Windshield wiper/washer switch terminal 4
* Analog clock terminal 3
* DIC switch terminal 4
* Radio terminal 8 X1

4. Command the dimming test high to low with a scan tool. The test lamp should turn from bright to dim when changing between the commanded states.

• If the test lamp is always off, test the control circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the BCM.


• If the test lamp is always bright, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the affected component.



Repair Instructions

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

* Refer to the appropriate replacement procedure for the component causing the condition.
* Programming and Relearning (Programming and Relearning)for BCM, driver door switch, and passenger door switch replacement, setup, and programming