ABS Light: Testing and Inspection

HARD WIRED LAMP DIAGNOSIS
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.

Anti-lock Brake System Lamp
The diagnosis found here addresses an inoperative Anti-lock Brake System (ABS) lamp condition. If no ABS problem is found, the following procedure will help locate a short or open in the ABS lamp 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. Remove the instrument cluster. Connect the battery negative cable, Thin the ignition switch to the ON position and within five seconds check for continuity between the ABS warning indicator driver circuit cavity of the instrument cluster wire harness connector A and a good ground. There should be continuity for five seconds after ignition On, and then an open circuit. If OK, replace the faulty bulb. If not OK, go to Step 4.
4. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the Controller Antilock Brake (CAB) wire harness connector. Check for continuity between the ABS warning indicator driver circuit cavity of the instrument cluster wire harness connector A and a good ground. There should be no continuity. If OK, go to Step 5. If not OK, repair the shorted ABS warning indicator driver circuit as required.
5. Check for continuity between the ABS warning indicator driver circuit cavities of the instrument cluster wire harness connector A and the CAB wire harness connector. There should be continuity. If not OK, repair the open ABS warning indicator driver circuit as required.