Diagram/Headlights/Daytime Running Lights (DRL) Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description
and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the X4 harness connector at the underhood fuse block.
2. Connect a test lamp between the control circuit terminal C3 and B+.
3. Command the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded
states.
锟斤拷 If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
锟斤拷 If the test lamp is always OFF, test the control circuit for a short to voltage or open/high resistance. If the circuit tests normal, replace the
BCM.
4. If all circuits test normal, test or replace the underhood fuse block.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Underhood Electrical Center or Junction Block Replacement (See: Maintenance/Fuses and Circuit Breakers/Fuse Block/Service and
Repair/Removal and Replacement/Underhood Electrical Center or Junction Block Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup, and programming
B2585
DTC B2585
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B2585 00
- Park Lamp Control Circuit
Diagnostic Fault Information
