Parking Brake System: Description and Operation

How the Circuit Works
The brake system indicator light comes on to alert the driver that the parking brake is applied, or that the brake fluid level is low. It also comes on as a bulb test when the engine is cranked.

Parking Brake
With the ignition switch in ON (II) or START (III), voltage is applied through fuse 13 to the gauge relay. The gauge relay then applies battery voltage through fuse 55 to the brake system indicator light. When you apply the parking brake, the switch closes and provides a ground for the light, and the light comes on to remind the driver that the parking brake is applied.