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 B2585 00: Left Parklamp Control Circuit

### Diagnostic Fault Information

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

### Circuit/System Description

Battery positive voltage is supplied to the PRK LAMP relay at all times. The body control module (BCM) grounds the park lamp relay control circuit in order to activate the relay. With the park lamp relay activated, voltage is supplied to the park lamp control circuit illuminating the park lamps, license lamps, and marker lamps.

### Conditions for Running the DTC

• | The ignition switch is in the RUN position.

• | The ambient light sensor senses a dark condition, automatic lamp control (ALC) park lamps ON, or the headlamp switch is in the park or head ON position.

### Conditions for Setting the DTC

The park lamp control circuit is shorted to voltage.

### Action Taken When the DTC Sets

The park lamps are inoperative.

### Conditions for Clearing the DTC

100 consecutive ignition cycles have been recorded without the DTC being detected.

### Reference Information

#### Schematic Reference

Exterior 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 park lamps ON and OFF with a scan tool, observe the operation of park lamps. The park lamps should turn ON and OFF with each command.

### Circuit/System Testing

1. Ignition OFF, disconnect the PRK LAMP relay.
2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 86 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