Test J: The Brake Warning Indicator Is Always On

PINPOINT TEST J: THE BRAKE WARNING INDICATOR IS ALWAYS ON

J1-J2:

J2-J5:

J6-J9:

J10-J11:

Normal Operation
The instrument cluster uses 2 separate strategies to operate the brake warning indicator. When the parking brake is applied, circuit 1309 (RD/YE) to the smart junction box (SJB) is grounded by the parking brake switch through circuit 1205 (BK). The SJB receives the ground signal and sends the instrument cluster a message over the communication network to illuminate the brake warning indicator. When the brake fluid level is low or a base brake system concern is detected, the anti-lock brake system (ABS) module sends a signal to the instrument cluster over the communication network to illuminate the brake system warning indicator.

DTC B2479 - sets when the SJB detects a short to ground from the parking brake switch input circuit. This DTC can only set when running the on-demand self-test.

DTC C1125 - sets when the SJB detects a short to ground from the brake fluid level switch input circuit. This DTC can only set when running the on-demand self-test.

Possible Causes
- Circuit 128 (VT/YE) open or short to ground
- Circuit 1305 (DB) open or short to ground
- Circuit 1309 (RD/YE) short to ground
- Parking brake switch
- Brake fluid level switch
- SJB
- ABS module
- Instrument cluster