Test L: Brake Warning Indicator Inoperative Or Always On
NOTE:
After repair, clear DTCs and repeat self-test.
- Check the base brake system. If brakes are okay, go to next step. If brakes are faulty, repair problem. See appropriate ANTI-LOCK article in BRAKES.
- Check parking brake control and brake fluid level. If parking brake control is fully disengaged and brake fluid level is correct, go to next step. If parking brake is not disengaged or brake fluid level is not correct, disengage parking brake and/or adjust fluid level.
- Turn ignition switch to OFF position. Disconnect parking brake switch connector. Measure resistance between parking brake switch terminal (component side) and ground while engaging and fully disengaging parking brake control. Resistance should be less than 5 ohms with parking brake engaged and greater than 10 k/ohms with parking brake fully disengaged. If resistance is as specified, go to next step. If either resistance is not as specified, replace parking brake switch.
- Turn ignition switch to OFF position. Disconnect instrument cluster 20-pin connector. Measure resistance of Light Green/Red wire between parking brake switch connector and instrument cluster 20-pin connector terminal No. 17. Measure resistance of Light Green/Red wire between instrument cluster 20-pin connector terminal 17 and ground. See Figure. Resistance is less than 5 ohms between instrument cluster connector and parking brake switch connector, and more than 10 k/ohms between instrument cluster connector and ground. If resistance is as specified, go to next step. If either resistance is not as specified, repair open or short to ground in Light Green/Red wire.
- Disconnect brake fluid level switch connector. Measure resistance between brake fluid level switch terminals No. 1 and 3 (component side). Measure resistance between brake fluid level switch terminals No. 2 and 3 (component side). See Fig 1. Resistance should be more than 10 k/ohms between fluid level switch terminals No. 1 and 3, and less than 5 ohms between 2 and 3. If resistance is as specified, go to next step. If either resistance is not as specified, replace brake fluid level switch.
- If vehicle is equipped with rear wheel anti-lock brakes, disconnect anti-lock brake control module 14-pin connector. Measure resistance between instrument cluster 20-pin connector terminal No. 18 (Dark Green/Yellow wire) and ground. Measure resistance between instrument cluster 20-pin connector terminal No. 19 (Tan/Light Green wire) and ground. See Figure. If each resistance is more than 10 k/ohms, go to next step. If either resistance is 10 k/ohms or less, repair short to ground in Dark Green/Yellow or Tan/Light Green wire .
- Measure resistance of Dark Green/Yellow wire between brake fluid level switch connector and instrument cluster 20-pin connector terminal No. 18. Measure resistance of Tan/Light Green wire between brake fluid level switch connector and instrument cluster 20-pin connector terminal No. 19. If each resistance is less than 5 ohms, go to next step. If either resistance is 5 ohms or more, repair open in Dark Green/Yellow or Tan/Light Green wire. See WIRING DIAGRAMS .
- Measure resistance of Black wire between brake fluid level switch connector and ground. If resistance is less than 5 ohms and vehicle has rear anti-lock brakes, go to next step. If resistance is less than 5 ohms and vehicle has 4-wheel anti-lock brakes, go to step 10. If resistance is 5 ohms or more, repair open in Black ground wire. Ground point is located at left front radiator support.
- Ensure rear anti-lock brake module is disconnected. Disconnect instrument cluster 20-pin connector. Disconnect parking brake switch connector. Disconnect brake fluid level switch connector. Turn ignition switch to RUN position. Observe red BRAKE indicator. If red BRAKE indicator illuminates, go to next step. If red BRAKE indicator does not illuminate, replace anti-lock brake module.
- Disconnect all instrument cluster connectors. Inspect connectors for corrosion and pushed out pins. Connect all instrument cluster connectors, ensuring they are connected correctly. Operate system and verify if concern is still present. If concern is still present, replace instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. If concern is not present, system is operating correctly at this time. Clear DTCs and repeat self-test.