Brake Warning Indicator: Testing and Inspection

Bulb Check
The instrument panel bulb can be checked each time the ignition switch is turned to the start position or the parking brake is set.

Pressure Differential Warning Light Switch Circuit Check
1. Raise and support vehicle, then open a wheel cylinder bleeder valve.
2. Press down on brake pedal and observe brake warning lamp. If lamp fails to illuminate, inspect for the following:
a. Faulty bulb.
b. Disconnected electrical socket.
c. A broken or disconnected wire at the switch, located in the brake line "T" fitting, mounted on frame rail in engine compartment below master cylinder.