B2585

DTC B2585

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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
- Park Lamp Control Circuit

Diagnostic Fault Information






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 and the body control module (BCM) commands the park lamps ON, the BCM then applies a ground to the park lamp relay control circuit. This engages the relay and applies voltage through the park lamp fuses and to all the park, license, and tail lamps.

Conditions for Running the DTC

* The Ignition is ON.
* The park lamps must be commanded ON by the BCM.

Conditions for Setting the DTC

The BCM detects a short to voltage on the park lamp relay control circuit.

Action Taken When the DTC Sets

All park, license, and tail lamps are inoperative.

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.
* The BCM receives the clear code command from the scan tool.

Circuit/System Verification

Ignition ON, activate the Parking Lamp output control on the scan tool. The Park Lamp Relay Command parameter in the data list should display On and the park lamps should illuminate.

Circuit/System Testing

1. Ignition OFF, remove the park lamp relay from the underhood fuse block.
2. Ignition ON, test for voltage at the relay control circuit terminal of the underhood fuse block.

• If voltage is present, test the control circuit for a short to voltage. If all circuits/connections test normal, replace the relay.

• If voltage is not present, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Relay Replacement (Within an Electrical Center) Relay Replacement (Attached to Wire Harness)
* Control Module References for BCM replacement, setup, and programming Programming and Relearning