Up to VIN S5219999

Brake fluid level switch
With the ignition switch in ON or START, and the brake fluid level switch closed, the brake warning light illuminates to warn the driver of low brake fluid level in the brake master cylinder.

Parking brake switch
With the ignition switch in ON or START and the parking brake switch closed, the brake warning light illuminates to remind the driver that the parking brake is applied.

Bulb test
With the ignition switch in START, ground is provided to the brake warning indicator through the ignition switch. This operation acts as a bulb test for the brake warning indicator.