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Antilock Brake System (ABS)






ANTILOCK BRAKE SYSTEM

The Antilock Brake System (ABS) prevents wheel lockup under braking conditions on virtually any type of road surface. Antilock braking is desirable because a vehicle that is stopped without locking the wheels retains directional stability and some steering capability. This allows the driver to retain greater control of the vehicle during braking.

This vehicle uses an antilock brake system designated MK25e. For this vehicle, MK25e is available with or without traction control. Traction control reduces wheel slip and maintains traction at driving speeds below 64 km/h (40 mph) when road conditions call for traction assistance. For more information on traction control, Description and Operation.

All vehicles equipped with ABS use electronic variable brake proportioning (EVBP) to balance front-to-rear braking when the brakes are applied in the partial braking range. For more information on electronic brake distribution, Description and Operation.

This system shares most base brake hardware used on vehicles without ABS. Included in the ABS system is an integrated control unit (ICU) and four wheel speed sensors. Although similar to vehicles without ABS, a different master cylinder and brake tubes are used.

The MK25e ICU is made up of the Hydraulic Control Unit (HCU) and the Antilock Brake Module (ABM). For additional information on these components, Anti-Lock Brake System Module - Description.