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

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


G1-G3:






G3-G6:






G6-G9:






G9-G10:






G11-G13:






G13-G16:






Normal Operation
When the parking brake is applied, circuit 409 (TN/BK) to the instrument cluster is grounded through the parking brake switch and circuit 57 (BK). The instrument cluster receives the ground signal and illuminates the BRAKE warning indicator. When the brake fluid level is low, circuit 977 (VT/WH) to the instrument cluster is grounded through the brake fluid level switch and circuit 57 (BK). The instrument cluster receives the ground signal and illuminates the BRAKE warning indicator. When a base brake system concern occurs, the anti-lock brake system (ABS) module sends a signal to the instrument cluster over the communication network to illuminate the BRAKE warning indicator. If communication between the instrument cluster and the ABS module is lost, the instrument cluster turns on the BRAKE warning indicator.

Possible Causes
- circuit 57 (BK) open
- circuit 409 (TN/BK) open or short to ground
- circuit 977 (VT/WH) open or short to ground
- parking brake switch
- brake fluid level switch
- ABS module
- instrument cluster