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B1480



DTC B1480

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 DESCRIPTOR

DTC B1480 00
Battery Rundown Protection Circuit




DIAGNOSTIC FAULT INFORMATION

CIRCUIT/SYSTEM DESCRIPTION
The INTERIOR LIGHTS fuse supplies battery voltage to the body control module (BCM). The 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 hatch 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, rearview mirror lamps, and rear compartment lamps. The BCM also provides a class 2 serial data message to the driver door module (DDM) and passenger door module (PDM) to apply battery voltage to the exterior courtesy lamps. In the event that any of these lamps were to remain illuminated for more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the courtesy lamp supply voltage circuit to prevent a total battery discharge condition. For more detailed information concerning courtesy lamp operation refer to Interior Lighting Systems Description and Operation.

CONDITIONS FOR RUNNING THE DTC
Battery voltage must be between 9-16 volts.

CONDITIONS FOR SETTING THE DTC
DTC B1480 will set when the courtesy lamp supply voltage circuit that feeds the courtesy lamps, underhood lamp, IP compartment lamp, console lamp and both visor vanity mirror lamps is shorted to ground for longer than 1 second.

Actions Taken When the DTC Sets
The courtesy lamps, underhood lamp, I/P compartment lamp, console lamp, and both visor vanity mirror lamps will not operate.

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

CIRCUIT/SYSTEM TESTING
1. Ignition OFF, disconnect the appropriate harness connector at each component fed by the courtesy lamp supply voltage circuit.
2. Ignition ON, verify that a test lamp illuminates between the courtesy lamp supply voltage circuit at each component harness connector and ground.
- If the test lamp does not illuminate, test the courtesy lamp supply voltage circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the BCM.
3. Connect each component one at a time and verify with a scan tool if the DTC resets as current.
4. If the DTC resets, test or replace the inoperative component.

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

- Instrument Panel Courtesy Lamp Bulb Replacement
- Instrument Panel Compartment Lamp Switch Replacement
- Underhood Lamp Replacement
- Cargo Lamp Replacement
- Rearview Mirror Replacement
- Sunshade Replacement
- Control Module References for BCM replacement, setup, and programming. Programming and Relearning