Brake Warning Indicator: Description and Operation

How the Circuit Works

The brake system indicator circuit alerts the driver that the parking brake is applied, or that the brake fluid level is low by illuminating the brake system indicator light. The light is also turned on by the "safety circuit" and the "test during START" circuit.

Parking Brake

With the ignition in ON (II) or START (III), battery voltage is supplied through fuse 5 and the brake system indicator light to the parking brake switch. With the parking brake on, the switch is closed, providing a ground for the light. The brake system indicator light reminds the driver that the parking brake is applied.

Brake Fluid Level

With the ignition in ON (II) or START (III), battery voltage is supplied through fuse 5 and the brake system indicator light to the brake fluid level switch. If the brake fluid level is low, the brake fluid level switch closes, and ground is provided to the circuit, turning on the brake system indicator light.

Bulb Check

When the ignition switch is first turned to ON (II), the "safety indicator" circuit in the gauge assembly tests the brake system indicator light by supplying a ground for several seconds to turn it on. When the ignition is turned to START (III), the "test during START' circuit tests the light by grounding it. With the ignition switch in ON (II) or START (III), battery voltage is supplied through fuse 5 and the YEL wire to the gauge assembly. With the ignition switch in START (III), battery voltage is supplied through fuse 7 and the BLK/WHT wire to the gauge assembly.