TEST 39B - Repairing Brake Warning Light & Brake Pressure Switch Problems
NOTE:
For connector terminal identification, see CONNECTOR IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS at the end of this article. Perform VERIFICATION PROCEDURE VER-1 after each repair.
CAUTION:
Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.
- If vehicle is equipped with anti-lock brakes, see appropriate ANTI-LOCK BRAKES article in the BRAKES Section. If vehicle is not equipped with anti-lock brakes, go to next step.
- Check brake fluid level in reservoir. If fluid level is not within specification, check for leaks and repair as needed. If fluid is within specification, go to next step.
- Depress brake pedal. If problem with service brakes exists, see appropriate BRAKES article in the BRAKES Section. If no problem with service brakes exists, go to next step.
- Observe brake warning light on dash. if brake light is on, go to next step. If brake light is off, go to TEST 39C.
- Disconnect brake pressure warning switch, located below master cylinder. Check, clean and repair connections as needed. If brake warning light goes out, replace brake pressure warning switch. If brake warning light does not go out, go next step.
- Disconnect instrument cluster Red connector. Check, clean and repair connections as needed. Put DRB-II in ohmmeter mode. Measure resistance in instrument cluster Red connector Gray/Black wire. If resistance is more than 5 ohms, replace instrument cluster. If resistance is less than 5 ohms, go to next step.
- Disconnect ignition switch connector. Check, clean and repair connections as needed. Measure resistance in instrument cluster Red connector Gray/Black wire. If resistance is more than 5 ohms, replace ignition switch. If resistance is less than 5 ohms, repair Gray/Black wire between ignition switch and instrument cluster Red connector for short to ground.