Circuit Operation

Battery voltage is applied to the "BRAKE" Warning Indicator when the Ignition Switch is in "RUN," "BULB TEST" or "START." Four switches are connected to the "BRAKE" Warning Indicator. When any of these switches close, ground is provided and the indicator lights.

The Ignition Switch provides a ground when it is in the "BULB TEST" and "START" positions.

The Park Brake Switch provides a ground when the Park Brake is applied.

The Brake Fluid Level Indicator Sensor closes to light the "BRAKE" Warning Indicator with low brake fluid in one of the two hydraulic brake fluid reservoirs. This could be caused by a leak in one of the brake lines. The sensor can be reset to "OPEN" by refilling the reservoir; however, this can only be accomplished after the system is repaired.

The Electronic Brake Control Module (EBCM) closes to light the "BRAKE" Warning Indicator and sets a diagnostic trouble code when an Antilock Brake System (ABS) failure will affect base brake operation.