B2558
DTC B2557 or B2558
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 Descriptors
DTC B2557
- Passenger Compartment Lamp Control Circuit Low
DTC B2558
- Passenger Compartment Lamp Control Circuit High
Diagnostic Fault Information
Circuit/System Description
The interior courtesy lamps consist of the dome lamp and the left and right footwell lamps. Battery voltage is supplied to the courtesy lamps by the body control module (BCM) through an inadvertent power supply circuit. In the event that any of these lamps were to remain illuminated for a period of more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply to prevent a total battery discharge condition. Courtesy lamp operation is controlled by the BCM through low side drive control circuits, and any time the inadvertent power supply is active the BCM turns on the courtesy lamps by grounding the control circuits.
Conditions for Running the DTC
The battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
B2557
The courtesy lamp supply circuit is shorted to ground.
B2558
The courtesy lamp control circuit is shorted to voltage.
Action Taken When the DTC Sets
The courtesy lamps will not operate or will remain always on.
Conditions for Clearing the DTC
* This DTC will clear on current status after the condition for setting the fault is corrected.
* A history DTC will clear after 100 consecutive ignition cycles without a fault present.
Reference Information
Schematic Reference
Interior Lights Schematics (Interior Lights Diagrams)
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 Verification
Ignition ON, command the courtesy lamps on and off with a scan tool.
If the courtesy lamps do not turn on or remain always on perform the Courtesy Lamp Control Circuit Test.
Circuit/System Testing
Courtesy Lamp Control Circuit Test
1. Ignition OFF, disconnect the affected courtesy or dome lamp.
2. Ignition ON, command the courtesy lamps on and off with a scan tool.
3. Verify that a test lamp turns on and off when connected from battery voltage to the control circuit terminal B.
• If the test lamp is always OFF, test the control circuit for an open/high resistance.
• If the test lamp is always ON, test the control circuit for a short to ground.
4. Connect a test lamp between the supply circuit terminal A and ground.
5. Ignition ON, verify that the test lamp illuminates.
• If the test lamp is always OFF, test the supply circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
6. If all circuits test normal, test or replace the bulb.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Dome Lamp Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, programming, and setup.