BRAKES - ABS SERVICE INFORMATION
DESCRIPTION
ANTILOCK BRAKE SYSTEM WITH TRACTION CONTROL - MK25
Early launch vehicles use the MK25 Antilock braking
system (ABS). This system, a combined ABS and
Traction Control system is standard on some vehicles
and optional on others.
This antilock brake system uses components of the
base brake system, but also features the following
components:
•
Integrated Control Unit (ICU) - Includes Hydraulic
Control Unit (HCU) (2) and Antilock Brake Mod-
ule (ABM) (3)
•
Wheel Speed Sensors (WSS) - Four sensors
(one at each wheel)
ABS
The purpose of the antilock brake system (ABS) is to prevent 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.
ALL-SPEED TRACTION CONTROL
The traction control system is an all-speed traction control. All-Speed Traction Control enhances mobility and pre-
vents wheel slip when accelerating on slippery surfaces. Depending on how slippery, an automatically activated
Winter Mode feature will select lower transmission up-shift speeds. It also provides a measure of directional stability
control. Using the wheel-speed sensors, it can detect excessive yaw and help keep the car on the intended course,
as for instance, when accelerating around a curve.
With rear-wheel drive, All-Speed Traction Control is effective up to 85 mph (137 km/h); with AWD, All-Speed Traction
Control is effective up to 45 mph (72 km/h), which is common among competitive AWD vehicles with traction control.
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BRAKES - ABS SERVICE INFORMATION
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