ABS Circuit Description

Circuit Description:


Battery voltage is supplied to the BRAKE WARNING INDICATOR when the ignition switch is in the run or start position. Two switches are connected to the BRAKE WARNING INDICATOR. When either one of these switches closes, a ground is provided and the BRAKE WARNING INDICATOR lights. The BRAKE WARNING INDICATOR is also connected to the electronic FOUR WHEEL BRAKE CONTROL MODULE.

The BRAKE PRESSURE WARNING SWITCH closes and provides a ground to light the BRAKE WARNING INDICATOR when there is low brake fluid pressure in of the two hydraulic brake systems. This could be caused by a leak in one of the brake lines. Refer to Brake Systems for Brake Pressure Switch reset procedure. This can only be accomplished after the faulty system has been repaired.

The electronic FOUR WHEEL ANTI-LOCK BRAKE CONTROL MODULE grounds the BRAKE WARNING INDICATOR and the ANTI-LOCK BRAKE WARNING INDICATOR lamps when the module senses a fault in the four wheel anti-lock brake system. The module also grounds the BRAKE WARNING INDICATOR for three seconds when the ignition is placed in RUN. Refer to brake systems for diagnosis.