Brake Warning Indicator Always On

Brake Warning Indicator Always On

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Diagnostic System Check - Vehicle
* Review Strategy Based Diagnosis for an overview of the diagnostic approach. Strategy Based Diagnosis
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The body control module (BCM) sends a serial data message to the instrument panel cluster (IPC) requesting illumination of the brake warning indicator when the park brake switch signal circuit is grounded.

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 the 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 the Park Brake Switch parameter. Verify the parameter is reading ON.
^ If parameter is OFF, replace the park brake switch.

3. Test the park brake switch signal circuit for a short to ground. Verify no short is found.
^ If 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
* Control Module References for IPC replacement, setup, and programming