Anti-Lock Brake System: Description
The Teves Mark IVG Anti-Lock Brake System (ABS) consists of Hydraulic Control Unit (HCU), Electronic Control Unit (ECU), acceleration switch, main relay and pump motor relay, ABS warning light, pump motor speed sensor, vacuum booster, master cylinder, 4 wheel speed sensors and axle shaft tone (pulse) rings. Teves Mark IVG ABS is not equipped with pedal travel sensor. See Fig 1 .
ABS control system is separate from other electrical circuits in vehicle. A separate ECU controls ABS operation. ABS hydraulic system is a 3 channel design. During ABS operation, front wheels are controlled individually and rear wheels are controlled together. ABS modulates brake fluid apply pressure during high pedal pressure and high vehicle deceleration to prevent wheel lock-up.