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 Descriptors

DTC B2562 00: Cargo Lamp Control Circuit Low
DTC B2563 00: Cargo Lamp Control Circuit High

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Cargo Lamp Switch Signal | B2562 00 | 1 | B2563 00 | --
Cargo Lamp Control | 2 | 2 | 2 | --
Headlamp and Panel Dimmer Switch Low Reference | -- | 1 | -- | --
Cargo Lamp Ground - Left | -- | 2 | -- | --
Cargo Lamp Ground - Right | -- | 2 | -- | --

1. Cargo Lamp Switch Malfunction
2. Cargo Lamp Malfunction

### Circuit/System Description

The cargo lamps are supplied voltage by a dedicated courtesy lamp supply voltage circuit or by turning the cargo lamp switch ON. When the cargo lamp switch is turned to the ON position or the door is opened, voltage is then supplied to cargo lamps by the BCM through the headlamp and panel dimmer switch. The cargo lamps are grounded at all times at G105.

### Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

### Conditions for Setting the DTC

#### B2562 00

The cargo lamp control circuit is shorted to ground.

#### B2563 00

The cargo lamp control circuit is shorted to voltage.

### Action Taken When the DTC Sets

The cargo lamps will not operate or will remain illuminated.

### Conditions for Clearing the DTC

• | The conditions 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 harness connector at the inoperative cargo lamp.
2. Test for less than 5 ohms between the ground circuit terminal B and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF.

⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the cargo lamp.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | High Mount Stop Lamp Replacement

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