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 B1480 00: Battery Rundown Protection Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Body Control Module (BCM) B+ Terminal 2 X3

B1480 00

B1480 00

--

--

Inadvertent Power Courtesy Lamp Control

B1480 00

1

--

--

Ground

--

1

--

1. Courtesy Lamps Malfunction

Circuit/System Description

The body control module (BCM) applies battery voltage to the courtesy lamps through the courtesy lamp supply voltage circuit. When any door is opened, the jam switch contacts close and the BCM receives a door-open input. If the BCM receives a door lock or unlock input or a rear compartment open input, the BCM will activate the courtesy lamp supply voltage circuit, providing battery voltage to all of the instrument panel (I/P) courtesy lamps, dome lamps, rearview mirror lamps, and rear compartment lamps. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power courtesy lamp control circuit to prevent a total battery discharge condition.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

The BCM detects a short ground in the inadvertent power courtesy lamp control circuit.

Action Taken When the DTC Sets

The BCM will deactivate inadvertent power to the courtesy lamps.

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 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 Testing

  1. Ignition OFF, disconnect the X3 harness connector at the BCM.
  2. Ignition ON, 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.
  4. Ignition OFF, connect the X3 harness connector at the BCM.
  5. Disconnect the harness connector at each component listed below:
  6. • Dome/reading Lamp
    • Left Vanity Mirror Lamp
    • Right Vanity Mirror Lamp
    • Reading Lamp Assembly
    • Inside Rearview Mirror Lamp
    • Rear Compartment Courtesy Lamp
  7. Ignition ON, verify that a test lamp illuminates between the control circuit at each component harness connector and ground.
  8. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the BCM.
  9. Connect each component one at a time and verify with a scan tool if the DTC resets as current.
  10. If the DTC resets, test or replace the inoperative component.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Headlamp Switch Replacement
    •  Sunshade Illuminated Mirror Lamp Bulb Replacement
    •  Sunshade Replacement
    •  Instrument Panel Courtesy Lamp Bulb Replacement
    •  Dome Lamp Replacement
    •  Inside Rearview Mirror Replacement
    •  Rear Compartment Courtesy Lamp Replacement
    •  Control Module References for BCM replacement, setup, and programming