Brake Warning Indicator: Testing and Inspection

The diagnosis found here addresses an inoperative brake indicator condition. If the brake indicator comes ON or stays ON with the ignition switch in the ON position and the park brake released, or comes ON while driving, the brake system must be diagnosed and repaired prior to performing the following tests. If no brake system problem is found, the following procedure will help locate a faulty park brake switch or park brake switch sense circuit.

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, SEAT BELT TENSIONER, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

1. Disconnect and isolate the battery negative cable. Disconnect the instrument panel wire harness connector for the park brake switch from the switch terminal. With the park brake released, check for continuity between the park brake switch terminal and a good ground. There should be no continuity. If OK, go to Step 2. If not OK, adjust or replace the faulty park brake switch.
2. Remove the instrument cluster from the instrument panel. With the park brake switch still disconnected, check for continuity between the park brake switch sense circuit cavity of the instrument panel wire harness connector for the park brake switch and a good ground. There should be no continuity. If OK, go to Step 3. If not OK, repair the shorted park brake switch sense circuit between the park brake switch and the instrument cluster as required.
3. Check for continuity between the park brake switch sense circuit cavities of the instrument panel wire harness connector for the park brake switch and the instrument panel wire harness connector (Connector C1) for the instrument cluster. There should be continuity. If OK, proceed with diagnosis of the instrument cluster. (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). If not OK, repair the open park brake switch sense circuit between the park brake switch and the instrument cluster as required.