Buick Regal: DTC B255F
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
- Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
DTC Descriptor
DTC B255F 02
Interior Door Handle Backlight Circuit Short to Ground
Diagnostic Fault Information
1. Interior Accent Lighting Malfunction
Circuit/System Description
The body control module (BCM) supplies battery voltage to accent lighting
lamps via the accent lamp
control circuit. When a door is opened the BCM applies battery voltage to the
accent lamp control circuit illuminating all of the accent lighting. The accent
lighting will remain illuminated until all doors
are closed and the ignition is OFF. The accent lighting remains illuminated with
the ignition ON.
Conditions for Running the DTC
Battery voltage must be between 9 - 16 V.
Conditions for Setting the DTC
DTC B255F 02
The BCM detects a short to ground in the accent lamp control circuit terminal
22 X7.
DTC B255F 04
The BCM detects a short to voltage or an open/high resistance in the accent
lamp control circuit terminal
22 X7.
Actions Taken When the DTC Sets
The BCM will disable the accent lamp 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 Wiring Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Interior Lighting Systems Description and Operation
Electrical Information Reference
- Circuit Testing
- Connector Repairs
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Testing
1. Ignition OFF, scan tool disconnected, all doors closed, all accessories
OFF, open and close drivers
door, disconnect the harness connector at the component with the inoperative LED
backlighting. It
may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 Ω between the appropriate ground circuit terminal and
ground.
- Ignition OFF.
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground
connection.
- Go to next step: If less than 10 Ω
3. Connect a test lamp between the appropriate control circuit terminal and
ground, ignition ON.
4. Verify the test lamp turns ON and OFF when commanding the Accent Lighting 1
ON and OFF
with a scan tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X7 harness connector at the K9 Body Control
Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- Go to next step: If infinite resistance
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- If the test lamp is always ON
- Ignition OFF, disconnect the X7 harness connector at the K9 Body Control
Module, ignition
ON.
- Test for less than 1 V between the control circuit terminal and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K9 Body Control Module.
- Go to next step: If the test lamp turns ON and OFF
5. Test or replace the accent lamp.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Front Side Door Map Pocket Illumination Lamp Replacement
- Front Side Door Inside Handle Illumination Lamp Replacement
- Rear Side Door Inside Handle Illumination Lamp Replacement
- Control Module References for BCM replacement, programming, and setup
READ NEXT:
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
SEE MORE:
This vehicle is equipped with
airbags.
Airbags are designed to inflate if the
impact exceeds the specific airbag
system's deployment threshold.
Deployment thresholds are used to
predict how severe a crash is likely
to be in time for the airbags to
inflate and help restrain the
occupants. The vehic
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic
procedure: Diagnostic
System Check - Vehicle
Review the description of Strategy Based Diagnosis: Strategy Based
Diagnosis
An overview of each diagnostic category can be found here: Diagnostic
Proced