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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2003 🢒 Savana 🢒 Body and Accessories 🢒 Lighting Systems 🢒 DTC B2615

DTC B2615 Without YF7

Circuit Description

The body control module (BCM) receives a ground signal from the door jamb, or courtesy lamp switch requesting courtesy/dome lamp illumination. When this occurs, the BCM directly sends a voltage through the courtesy lamp supply voltage circuit illuminating the courtesy/dome lamps.

Voltage for the courtesy lamp supply voltage circuit as well as the backup lamp supply voltage circuit is from the body fuse block TBC 2 fuse directly through the BCM to these circuits.

Conditions for Running the DTC

The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC
    • When the BCM receives a courtesy lamp illumination request signal and the courtesy lamp supply voltage circuit is shorted to ground.
    • When the BCM is not receiving a courtesy lamp illumination request signal and the courtesy lamp supply voltage circuit is open before the first connection after the BCM or shorted to voltage.
    • There is a loss of the body fuse block TBC 2 battery supply voltage to the BCM for 1 second.

Action Taken When the DTC Sets

The courtesy dome lamps will not operate or are always ON.

Conditions for Clearing the MIL/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.
    • History and current DTCs can be cleared using a scan tool.

Diagnostic Aids
    • Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • An open circuit up to the first splice only in the courtesy lamp supply voltage circuit from the BCM, will set the DTC.
    • A short to ground in the following circuits will cause the TBC 2 fuse to open.
       - Courtesy lamp supply voltage.
       - Backup lamp supply voltage.
       - Battery positive voltage from the body fuse block TBC 2 fuse.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step test determines if the problem is a short to ground in the wiring.

    2.

  2. This step test determines if the problem exists in the wiring or the BCM.

    3.

  3. This step test determines if the problem exists in the wiring or the BCM.

    4.

  4. After replacement of the BCM you must calibrate the new module for proper operation.

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Inspect the TBC 2 fuse in the body fuse block.

Is the fuse open?

Go to Step 3

Go to Step 4

3

Test the following circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems:

    • Courtesy lamp supply voltage
    • Backup lamp supply voltage
    • TBC 2 battery positive voltage to the BCM

Did you find and correct the condition?

Go to Step 7

Go to Step 5

4

Test the courtesy lamp supply voltage circuit for an open, high resistance, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 7

Go to Step 5

5

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 7

Go to Step 6

6

Important: Perform the setup procedure for the BCM.

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 7

--

7
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK

DTC B2615 With YF7

Circuit Description

The body control module (BCM) receives a ground signal from the door jamb or courtesy lamp switches requesting courtesy/dome lamp illumination. When this occurs, the BCM sends a voltage through the courtesy lamp high control circuit to the courtesy lamp relay, illuminating the courtesy/dome lamps.

Voltage for the courtesy lamp high control circuit as well as the backup lamp supply voltage circuit is from the body fuse block TBC 2 fuse directly through the BCM to these circuits.

Conditions for Running the DTC

The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC
    • When the BCM receives a courtesy lamp illumination request signal and the courtesy lamp high control circuit is shorted to ground.
    • When the BCM is not receiving a courtesy lamp illumination request signal and the courtesy lamp high control circuit is open or shorted to voltage.
    • When the courtesy lamp relay coil side is open.
    • There is a loss of the body fuse block TBC 2 battery supply voltage to the BCM for 1 second.

Action Taken When the DTC Sets

The courtesy dome lamps will not operate or are always ON.

Conditions for Clearing the MIL/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.
    • History and current DTCs can be cleared using a scan tool.

Diagnostic Aids
    • Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • A short to ground in the following circuits will cause the TBC 2 fuse to open.
       - Courtesy lamp high control.
       - Backup lamp supply voltage.
       - Battery positive voltage from the body fuse block TBC 2 fuse.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for an open coil in the courtesy lamp relay.

    2.

  2. After replacement of the BCM you must calibrate the new module for proper operation.

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Inspect the TBC 2 fuse in the body fuse block.

Is the fuse open?

Go to Step 3

Go to Step 4

3

Test the following circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems:

    • Courtesy lamp high control
    • Backup lamp supply voltage
    • TBC 2 battery positive voltage to the BCM

Did you find and correct the condition?

Go to Step 9

Go to Step 6

4

Test the courtesy lamp high control circuit for an open, high resistance, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Test the courtesy lamp relay between the ground terminal and the courtesy lamp high control terminal for continuity. Refer to Testing for Continuity in Wiring Systems.

Is continuity present?

Go to Step 6

Go to Step 7

6

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the courtesy lamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 9

--

8

Important: Perform the setup procedure for the BCM.

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 9

--

9
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK