GM Service Manual Online
For 1990-2009 cars only

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 B2615 00: Passenger Compartment Dimming 2 Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+, BCM X4 Terminal 2

B2615 00

B2615 00

--

--

Courtesy Lamps Supply Voltage

B2615 00

2

1

--

Right Front Turn Signal Lamp Supply Voltage

B2615 00

3

4

--

1. Courtesy Lamps Always On

2. Courtesy Lamps Inoperative

3. Right Front Turn Signal Inoperative

4. Right Front Turn Signal Always ON

Circuit/System Description

Battery voltage for the courtesy lamps is supplied at all times, from the CTSY/RF TRN Fuse located in the rear fuse block, to the body control module (BCM). When the BCM receives a signal to command the courtesy lamps ON, it then applies voltage through the courtesy lamps supply voltage circuits to the courtesy lamps listed below.

    • Left and right roof rail courtesy/reading lamps
    • Overhead console lamp

Conditions for Running the DTC

    • The BCM attempts to illuminate the courtesy lamps.
    • Engine ON, the BCM attempts to illuminate the day time running lamps.
    • Ignition ON with the right turn signal switch active, the BCM attempts to illuminate the right front turn signal.

Conditions for Setting the DTC

    • The BCM detects a short to ground on the courtesy lamp supply voltage circuit.
    • The BCM detects a short to ground on the right front turn signal supply voltage circuit.

Action Taken When the DTC Sets

The BCM will not attempt to activate courtesy lamps or the right front turn signal.

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 Schematics

Connector End View Reference

Component Connector End Views

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 Verification

Ignition ON, command the Courtesy Lamps ON and OFF with a scan tool. The courtesy lamps should turn ON and OFF when changing between commanded states.

Circuit/System Testing

  1. Ignition OFF, disconnect the X4 harness connector at the BCM.
  2. Verify that a test lamp illuminates between the B+ circuit terminal 2 and ground.
  3. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the supply voltage circuits listed below for a short to ground.
    • Right front turn signal lamp supply voltage terminal 5 X4
    • Courtesy lamp supply voltage terminal 1 X6
    • Courtesy lamp supply voltage terminal 5 X2
  4. Ignition OFF, connect the X4 harness connector at the BCM.
  5. Disconnect the harness connectors at all components fed by the supply voltage circuits listed below.
  6. • Right front turn signal lamp supply voltage terminal 5 X4
    • Courtesy lamp supply voltage terminal 1 X6
    • Courtesy lamp supply voltage terminal 5 X2
  7. Ignition ON, clear the DTC with a scan tool.
  8. Operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.
  9. If the DTC resets, test the supply voltage circuits for a short to ground. If the circuits test normal, replace the BCM.
  10. Reconnect each component one at a time and verify that the DTC does not reset.
  11. If the DTC resets, test or replace the component responsible for setting the DTC.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Roof Rail Rear Courtesy Lamp Replacement
    •  Overhead Console Reading Lamp and Bulb Replacement
    •  Control Module References for BCM replacement, setup, and programming