B1480

DTC B1480

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B1480 02
- Battery Rundown Protection Circuit Short to Ground

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) supplies battery voltage to the front reading lamps and left and right sunshade lamps via the courtesy lamp control circuit. When a sunshade mirror is opened, the switch contact close allowing battery voltage to flow illuminating the respective lamps. The front reading lamps are controlled by individual switches that are activated by the operator when additional cabin lighting is required. In the event that any of these courtesy lamps were to remain illuminated for more than 10 minutes with the vehicle ON/OFF switch in the OFF position and no doors opened, the BCM will deactivate the courtesy lamp control circuit to prevent total battery discharge.

Conditions for Running the DTC

Battery voltage must be between 9-16 V.

Conditions for Setting the DTC

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

Actions Taken When the DTC Sets

The BCM will disable the circuit and the sunshade lamps and front reading lamps will be inoperative.

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 vehicle ON/OFF switch cycles have occurred.

Diagnostic Aids

When the F7DR (INT LAMPS) fuse is open, both dome lamps, sunshade lamps, reading lamps, and backup lamps will be inoperative. DTC B2545 will also set for the backup lamps when the vehicle is placed in the reverse gear.

Reference Information

Schematic Reference

* Interior Lights Schematics Interior Lights Schematics

* Body Control System Schematics [1][2]Body Control Systems

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1

Description and Operation

Interior Lighting Systems Description and Operation Interior Lighting Systems

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Programming and Relearning for scan tool information

Circuit/System Testing

1. Vehicle OFF, exterior lamps OFF, disconnect the harness connectors at the components listed below.

* E37F dome/reading lamps - front

* E31L sunshade mirror lamp - left

* E31R sunshade mirror lamp - right

2. Connect a test lamp between the appropriate control circuit terminal listed below and ground, vehicle in Service Mode.

* E37F dome/reading lamps - front terminal 1

* E31L sunshade mirror lamp - left terminal A

* E31R sunshade mirror lamp - right terminal A

3. Verify the test lamp turns ON and OFF when commanding the Inadvertent Load ON and OFF with a scan tool.

• If the test lamp is always OFF

1. Vehicle OFF, disconnect the X7 harness connector at the K9 body control module.

2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance

3. Test for less than 2 ohms in the control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K9 body control module.

• If the test lamp is always ON

1. Vehicle OFF, disconnect the X7 harness connector at the K9 body control module, vehicle in Service Mode.

2. Test for less than 1 V between the control circuit terminal and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V, replace the K9 body control module.

• If the test lamp turns ON and OFF

4. Test or replace the appropriate courtesy lamp.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Sunshade Illuminated Mirror Lamp Bulb Replacement Sunshade Illuminated Mirror Lamp Bulb Replacement

* Dome and Reading Lamp Replacement Service and Repair

* Control Module References Programming and Relearning for BCM replacement, programming, and setup