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 B2530 00: Front Fog Lamp Control Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Front Fog Lamp Relay Control | 1 | 2 | B2530 00 | --
1. Fog Lamps Always On 2. Fog Lamps Inoperative

### Circuit/System Description

Voltage is applied at all times to the fog lamp relay. When the fog lamp switch is placed in the ON position, a ground signal is applied to the body control module (BCM) through the fog lamp switch signal circuit. The BCM then applies a ground to the fog lamp relay control circuit. This engages the fog lamp relay and applies voltage through the FOG LAMP fuse to the front fog lamps.

### Conditions for Running the DTC

• | The ignition is ON.

• | Park lamps must be ON and the fog lamps must be commanded ON.

### Conditions for Setting the DTC

The BCM detects a short to voltage on the front fog lamp control circuit.

### Action Taken When the DTC Sets

The front fog lamps do not illuminate.

### Conditions for Clearing the DTC

• | The conditions for setting the DTC are no longer present.

• | A history DTC clears after 100 malfunction-free ignition cycles.

### Reference Information

#### Schematic Reference

Fog Lights Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Exterior 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 Verification

Ignition ON, command the Fog Lamps ON with a scan tool. The Front Fog Lamp Relay Command parameter should display On and the front fog lamps should illuminate.

### Circuit/System Testing

1. Ignition OFF, disconnect the fog lamp relay.
2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 85 and ground.

⇒ | If the test lamp illuminates, test the control circuit for a short to voltage.

3. If all circuits test normal, replace the BCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Relay Replacement

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