Brake Fluid Level Sensor/Switch: Description and Operation

Circuit Description
The brake warning light goes on to alert the driver that the parking brake is applied or that the brake fluid level is low. It also lights as a bulb test when the engine is cranked.

Brake Fluid Level
With the ignition switch in ON or START, battery voltage is applied from fuse 10 to the brake warning light.

If the brake fluid level is low, the brake fluid level switch closes and ground is provided to the circuit. The brake warning light lights to warn the driver of low brake fluid level in the brake master cylinder. (Note: Check brake pad wear before adding fluid.)