B2625

DTC B2625

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptor
DTC B2625 00
- Passenger Compartment Dimming Request Signal Circuit Voltage Below Threshold

Diagnostic Fault Information





Circuit/System Description

The instrument panel (I/P) lamp dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The I/P dimmer switch provides a voltage signal that will increase as the brightness of the lights are increased and decrease as the brightness of the lights are decreased. The body control module (BCM) provides a B+ voltage reference to the I/P dimmer switch. When the I/P dimmer switch is placed in the desired position, the dimmed voltage setting is applied from the I/P dimmer switch through the I/P dimmer switch signal circuit to the BCM. The BCM interprets the signal and applies the dimmed voltage to the I/P lamps supply voltage circuit and the interior backlighting components dim to the requested level. Ground for the I/P dimmer switch is provided at G201.

Conditions for Running the DTC

* Battery voltage must be between 9-16 volts.
* Park lamps ON.

Conditions for Setting the DTC

DTC B2625 00 will set when the BCM detects a short to ground in the indicator dimming control circuit.

Action Taken When the DTC Sets

The BCM will not illuminate the indicators supplied by the indicator dimming control circuit.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Reference Information
Schematic Reference

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

Component Connector End Views (Connector 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

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connectors at the following components:

* Headlamp switch
* Heated seat switch - driver
* Heated seat switch - passenger
* Hazard switch

2. Ignition ON, with a scan tool clear the DTC and operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.

• If DTC B2625 00 sets as current, test the control circuits listed below for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

* Dimming control terminal 25 X3
* Dimming control terminal 25 X7

3. Reconnect each component one at a time and verify that the DTC does not reset as current after each component is reconnected.

• If the DTC sets as current, test or replace the component responsible for setting the DTC.

Repair Instructions

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

* Hazard Warning Switch Replacement (Service and Repair)
* Headlamp Switch Replacement (Service and Repair)
* Front Seat Heater Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming