Antilock Brakes / Traction Control Systems: Description and Operation

Fig. 1 ABS Component Locations:

Fig. 2 ABS Components:

Fig. 3 ABS System Diagram:

Fig. 4 Block Diagram Of ABS Electronic Circuits:

The Anti-lock brake system (ABS) electrically controls brake fluid pressure to prevent wheel lock during braking on slippery road surfaces, improving steering stability and shortening the braking distance. If the ABS becomes inoperative, a fail-safe system activates to ensure conventional brake system operation.
The front and rear wheels utilize a four sensor, four channel control design. The front wheels have an independent design which controls fluid pressure to the left and right wheels. The rear wheels have a select low design, which provides the same pressure for the two rear wheels if either starts to lock.
The ABS consists of four tone wheels, four speed sensors, electronic control unit, a G sensor, and a warning lamp. Refer to Figs. 1 through 4, for ABS component location and function.