For 1990-2009 cars

### 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
--- | --- | --- | --- | ---
12 Volt Reference | B1480 00 | 1 | -- | --
Ground | -- | 1 | -- | --
1. Courtesy Lamps Malfunction

### Circuit/System Description

Battery voltage is applied at all times to the body control module (BCM) from the INT LAMPS Fuse located in the rear fuse block. The BCM then applies this voltage to the following lamps:

• | Dome lamp

• | Inside rear view mirror lamps

• | Rear compartment courtesy lamp

In the event that any of these lamps were to remain illuminated for more the 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power courtesy lamps circuit to prevent total battery discharge.

### Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

### Conditions for Setting the DTC

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

### Action Taken When the DTC Sets

The BCM will deactivate the inadvertent voltage 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 the 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 appropriate harness connector at each component fed by the inadvertent power courtesy lamp circuit.
2. Ignition ON, with a scan tool clear the DTC.
3. Operate the system within the Conditions for Running the DTC and verify the DTC does not reset.

⇒ | If the DTC resets, test the inadvertent power courtesy lamp circuit for a short to ground. If the circuit tests normal, replace the BCM.

4. Connect each component one at a time and verify that the DTC does not reset. 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.

• | Reading Lamp Replacement

• | Dome Lamp Replacement

• | Cargo Lamp Replacement

• | Control Module References for BCM replacement, setup, and programming