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 02
- Display Dimming Pulse Width Modulation (PWM) Output Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
When the headlamp switch is placed in either the HEAD or PARK position, ground is applied to the park lamp signal circuit to the body control module (BCM). The BCM responds by applying ground to the park lamp relay control circuit. This energizes the park lamp relay coil causing the relay switch contacts to close allowing battery voltage to flow to all of the park, tail, license, marker lamps, interior ambient lighting, and to the BCM. The BCM receives the voltage from the park lamp relay indicating the park lamps are ON. The BCM uses this signal to command the interior backlighting ON and OFF. 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 signal and a low 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 indicator dimming control circuit and the interior backlighting components dim to the requested level.
Conditions for Running the DTC
* Battery voltage must be between 9-16 volts.
* Park lamps ON.
Conditions for Setting the DTC
DTC B2625 02 will set when the BCM detects a short to ground in the indicator dimming control circuit.
Action Taken When the DTC Sets
When DTC B2625 02 is present, the BCM will not illuminate the interior backlighting 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-free 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:
* Automatic transmission control indicator
* Console flood lamp
* Door lock switch - driver
* Door lock switch - front passenger
* Fog lamp switch
* Hazard Switch
* HVAC control module
* Left rear access panel release switch - driver
* Outside rearview mirror switch
* Radio
* Right rear access panel release switch - driver
* Right rear access panel release switch - passenger
* SWC BKLT fuse
* Traction control switch
* Turbo boost gage - with LNF
* Window switch - driver
* Window switch - front passenger
* Windshield wiper/washer switch - rear
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 02 sets as current, test the indicator dimming control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
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.
* Door Lock Switch Replacement (Service and Repair)
* Front Side Door Window Switch Replacement (Front Side Door Window Switch Replacement)
* Fog Lamp Switch Replacement (Service and Repair)
* Hazard Warning Switch Replacement (Service and Repair)
* Transmission Floor Shift Control Indicator Lamp Replacement (Service and Repair)
* Rear Window Wiper and Washer Switch Replacement (Rear Window Wiper and Washer Switch Replacement)
* Front Floor Console Flood Lamp Replacement (with Sunroof) (Front Floor Console Flood Lamp Replacement (with Sunroof))Front Floor Console Flood Lamp Replacement (w/o Sunroof) (Front Floor Console Flood Lamp Replacement (w/o Sunroof))
* Supercharger Boost Air Pressure Indicator Replacement (Service and Repair)
* Power Mirror Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM, HVAC control module, or Radio replacement, setup, and programming