Test K: The Brake Warning Indicator Is Never/Always On

PINPOINT TEST K: THE BRAKE WARNING INDICATOR IS NEVER/ALWAYS ON

K1-K3:

K4-K7:

K7-K9:

K9-K11:

K12-K14:

Normal Operation
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, the brake fluid level switch closes, providing a signal to the SJB on circuit 547 (LG/YE) is routed back to the SJB on the signal return circuit 512 (TN/LG). When 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 on-demand if the SJB detects that the parking brake is applied during the on-demand self-test or if there is a short to ground on the parking brake input circuit 1309 (RD/YE).

DTC C1189 - sets on-demand or continuously if the SJB detects that the brake fluid is low or there is a short to ground on the brake fluid level input circuit 547 (LG/YE).

Possible Causes
- Circuit 512 (TN/LG) open or short to ground
- Circuit 547 (LG/YE) open or short to ground
- Circuit 1205 (BK) open
- Circuit 1309 (RD/YE) open or short to ground
- Parking brake switch
- Brake fluid level switch
- SJB
- Instrument cluster