Test J: The Brake Warning Indicator Is Always On

PINPOINT TEST J: THE BRAKE WARNING INDICATOR IS ALWAYS ON

Normal Operation
When the parking brake is applied, the parking brake warning indicator switch grounds circuit CCB09 (GY/BU) to the smart junction box (SJB). The SJB receives the ground signal and sends the instrument cluster (IC) a message over the communication network to illuminate the brake warning indicator. When the brake fluid level is low, the brake fluid level switch closes, the signal from the SJB on circuit CMC19 (GY/VT) is grounded on circuit GD121 (BK/YE). When the ABS module detects a base brake system concern or other ABS related concerns that affect the electronic brake distribution (EBD) function, the ABS module sends a message to the instrument cluster (IC) to illuminate both the ABS warning indicator and the brake warning indicator.

NOTE: When the ABS module detects an electronic brake distribution (EBD) fault, the ABS module sends a message to the instrument cluster (IC). Whenever the instrument cluster (IC) receives an EBD message from the ABS module, the instrument cluster (IC) illuminates both the brake warning indicator and the ABS warning indicator simultaneously.

- DTC B2479 (Brake Park Switch Circuit Short to Ground) - is an on-demand DTC that sets in the SJB if a short to ground is detected on the parking brake input, circuit CCB09 (GY/BU).
- DTC C1125 (Brake Fluid Level Sensor Input Circuit Failure) - is an on-demand DTC that sets in the SJB if a short to ground is detected on the brake fluid level input, circuit CMC19 (GY/VT).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Parking brake warning indicator switch
- Brake fluid level switch (part of the brake fluid reservoir)
- Base brake system
- SJB
- Instrument cluster (IC)

J1-J3:

J4-J8:

J9-J12: