For 1990-2009 cars

### Diagnostic Instructions

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

• | Strategy Based Diagnosis

• | Diagnostic Procedure Instructions

### DTC Descriptors

DTC B2585 00: Park Lamp Control Circuit - Domestic
DTC B2585 00: Left Park Lamp Control Circuit - Export

### Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Park Lamp Relay Control Circuit | 2 | 1 | B2585 00 | --

1. Park Lamps Inoperative
2. Park Lamps Always On

### Circuit/System Description

Voltage is applied at all times to the Park Lamp Relay from battery voltage. When the headlamp switch is placed in the PARK position, ground is applied through the park lamp switch signal circuit to the body control module (BCM) . The BCM then applies a ground to the park lamp relay control circuit. This engages the relay that is soldered to the underhood fuseblock circuit board and applies voltage through the park lamp fuses and to all the park lamps.

### Conditions for Running the DTC

The ignition is ON. The park lamps must be commanded on by the headlamp switch.

### Conditions for Setting the DTC

The BCM detect a short to voltage on the park lamp relay control circuit while trying to apply a ground to the circuit.

### Action Taken When the DTC Sets

All park lamps are inoperative.

### Conditions for Clearing the DTC

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

### Reference Information

#### Schematic Reference

Exterior 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. The park lamps should illuminate.

### Circuit/System Testing

1. Clear the DTC, ignition OFF, park lamp switch OFF, disconnect the park lamp pcb relay at the underhood fuseblock terminals C3 pin 16 and C2 pin 22
2. Verify a test lamp illuminates between the negative battery terminal and the park lamp relay control circuit.

⇒ | If the test lamp does not illuminate replace the underhood fuseblock.

3. Test for a short to voltage in the park lamp relay control circuit.

⇒ | 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