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 Control Circuit | 2 | 1 | B2530 | --

1. Fog Lamps Inoperative
2. Fog Lamps Always On

### Circuit/System Description

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

### Diagnostic Aids

There are certain relays that are PCB or soldered to the underhood fuseblock circuit board and any relay replacement would warrant a replacement of the underhood fuseblock.

### 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 relay control circuit while trying to apply a ground to the circuit.

### Action Taken When the DTC Sets

The fog lamps do not illuminate.

### Conditions for Clearing the DTC

The BCM clears this code from current when the fault is removed from the system.

### Reference Information

#### Schematic Reference

Fog Lights Schematics

#### Connector End View Reference

Lighting Systems Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Verification

Ignition ON, turn the park lamps ON. Press the front fog lamp switch. The front fog lamps should illuminate.

### Circuit/System Testing

1. Clear the DTC. Park lamp switch OFF, fog lamp switch OFF. Disconnect the underhood fuseblock terminal C2 pin 19. Using a test lamp connected to ground, probe the fog lamp control circuit. Verify the test lamp illuminates.

⇒ | If the test lamp does not illuminate, replace the Underhood Fuseblock.

2. Test for a short to voltage in the fog lamp control circuit, Underhood Fuseblock terminal C2 pin 19.

⇒ | If all circuits/connections test normal, replace the BCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Underhood Electrical Center or Junction Block Replacement

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