Brake Fluid Level Sensor/Switch: Description and Operation

The "BRAKE" warning light goes on to alert the driver that the parking brake is applied or that the brake fluid level switch (ABS) is closed. It also lights as a bulb test when the engine is cranked.

Parking Brake Switch
With the starter switch in ON or START, battery voltage is applied to fuse C-10 and to the "BRAKE" warning light. When the parking brake is applied, the parking brake switch closes and provides a ground for the light. The "BRAKE" warning light goes on to remind the driver that the parking brake is applied.

Brake Fluid Level Switch
With the starter switch in ON or START; battery voltage is applied to fuse C-10 and to the "BRAKE" warning light. If the brake fluid is low, the brake fluid level switch closes and provides a ground for the light. The "BRAKE" warning light goes on to warn the driver of low brake fluid level in the brake master cylinder. (Note: check brake pad wear before adding fluid.)

Bulb Check
With the starter switch in START; battery voltage is applied to the "BRAKE" warning light. The generator will provide ground until the engine is running. The "BRAKE" warning light goes on to test the brake warning light bulb and then goes off. See Charging System for further details.