Test A: The Red Brake Warning Indicator Is Always on

Test A: The Red Brake Warning Indicator Is Always On

Refer to Vehicle/Diagrams for schematic and connector information.

Normal Operation
The red brake warning indicator is located in the instrument cluster and illuminates during prove out, when the brake fluid in the brake master cylinder reservoir is below a specific level, when the parking brake is engaged or if there is a diagnostic trouble code (DTC) in the anti-lock brake system (ABS). When the brake fluid level is low, the flotation device closes the brake fluid level switch, connecting circuit 57 (BK) to circuit 997 (VT/WH) and providing a ground path for the indicator in the instrument cluster. When the parking brake is engaged, the parking brake switch closes, connecting circuit 409 (TN/BK) with circuit 57 (BK). This connection provides a ground path for the indicator in the instrument cluster along circuit 977 (VT/WH). When there is a fault in the anti-lock brake system, the ABS module communicates with the instrument cluster along the high speed communication area network (HS-CAN) bus and the cluster illuminates the indicator.

Possible Sources
^ Brake fluid level
^ Circuit shorted
^ Brake fluid level switch
^ Parking brake switch
^ Instrument cluster
^ ABS module

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