Brake Warning Indicator Always On

Brake Warning Indicator Always On

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.

Circuit/System Description

The body control module (BCM) sees the park brake switch and brake fluid level switch input to grounded, it sends a serial data message to the instrument panel cluster (IPC) requesting illumination of the red brake indicator.

Reference Information

Schematic Reference

Hydraulic Brake Schematics

Connector End View Reference

Hydraulic Brake Connector End Views

Description and Operation

Brake Warning System Description and Operation

Electrical Information Reference

* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Testing

1. With the scan tool, select instrument panel special functions Lamp Test. Command the instrument panel lamps OFF. Verify brake lamp turns OFF.

^ If the brake lamp does not turn OFF, replace the IPC.

2. Disconnect the park brake switch, with a scan tool observe park brake switch parameter. Verify parameter is reading ON.
^ If parameter is OFF, replace the park brake switch.

3. Test the signal circuit of the park brake switch for a short to ground. Verify no short is found.
^ If a short is found, repair the circuit.

4. Replace the BCM.

Repair Instructions

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

* Park Brake Warning Lamp Switch Replacement
* Refer to Programing and Relearning Programming and Relearning