B2555

DTC B2555

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

DTC DESCRIPTORS

DTC B2555 00
Passenger Compartment Lamp Control Circuit




DIAGNOSTIC FAULT INFORMATION

CIRCUIT/SYSTEM DESCRIPTION
When the body control module (BCM) signals for courtesy lamp operation, a message is sent over the GMLAN serial data circuit to the driver door and passenger door switches. The driver door switch and passenger door switch the applies battery voltage to the left and right courtesy lamp control circuits illuminating the door courtesy lamps. The driver door and passenger door switches also provide ground to the lamps.

CONDITIONS FOR RUNNING THE DTC
- Battery voltage must be between 9-16 volts.
- A message is sent from the BCM over the GM LAN serial data circuit to the driver door and passenger door switches to active the door courtesy lamps.

CONDITIONS FOR SETTING THE DTC
- DTC B2555 00 will set when the driver or passenger door switch detects a short to voltage in the courtesy lamp control circuit.
- DTC B2555 00 will set when the driver or passenger door switch detects a short to ground in the courtesy lamp control circuit.

ACTION TAKEN WHEN THE DTC SETS
DTC B2555 00 is present, when a short to ground or short to voltage on the courtesy lamp control circuit is present.

CONDITIONS FOR CLEARING THE DTC
- The condition responsible for setting the DTC no longer exists.
- A scan tool CLEAR DTCs command is issued for that switch module.
- A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.

CIRCUIT/SYSTEM TESTING
1. Disconnect the driver or passenger door harness connector X2 terminal 11 as applicable.
2. Connect a test lamp between the courtesy lamp control circuit terminal 5 or 1 at the BCM connector and ground.
- If the test lamp illuminates, locate and repair a short to voltage in the courtesy lamp control circuit.
- If the test lamp does not illuminate, locate and repair a short to ground in the courtesy lamp control circuit.
3. If circuits test OK, replace the driver or passenger door switch as applicable.

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

Programming and Relearning Programming and Relearning