Brake Warning Indicator: Testing and Inspection

On each of the lamps found depends upon a hard wired circuit input to the instrument cluster for proper operation. The following procedures will help to diagnose conditions that may cause an inoperative hard wired lamp circuit condition.

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIRBAGS AND SEAT BELTS/AIRBAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

Brake Warning Lamp
The diagnosis found here addresses an inoperative brake warning lamp condition. If the brake warning lamp stays on with the ignition switch in the ON position and the park brake released, or comes on while driving, refer to Rear Wheel Antilock for vehicles equipped with a rear wheel anti-lock brake system, or refer to Antilock Brakes. If no brake system problem is found, the following procedure will help locate a faulty park brake switch or park brake switch sense circuit.
1. Check the fused ignition switch output (run/ start) fuse in the junction block. If OK, go to Step 2. If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
2. Turn the ignition switch to the ON position. Check for battery voltage at the fused ignition switch output (run/start) fuse in the junction block. If OK, go to Step 3. If not OK, repair the open fused ignition switch output (run/start) circuit to the ignition switch as required.
3. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the wire harness connector at the park brake switch. 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 4. If not OK, adjust or replace the faulty park brake switch.
4. Remove the instrument cluster. With the park brake switch wire harness connector still disconnected, check for continuity between the park brake switch sense circuit cavity of the park brake switch wire harness connector and a good ground. There should be no continuity. If OK, go to Step 5. If not OK, repair the shorted park brake switch sense circuit as required.
5. Check for continuity between the park brake switch sense circuit cavities of the instrument cluster wire harness connector A and the park brake switch wire harness connector. There should be continuity. If OK, refer to Instrument Cluster - Preliminary Diagnosis for further testing of the brake warning lamp and the instrument cluster circuitry. If not OK, repair the open park brake switch sense circuit as required.