ASR is anti skid regulation. It's basicly your average traction control system.

BAS is brake assist system. It detects when you are rapidly applying the brakes and applies full vacuum boost to your braking effort to help reach ful braking potential quicker (to shorten stopping distance).

ESP is electronic stability programme. It is the latest in traction control systems. It can apply brakes to each wheel individually using a modified version of the traditional abs pump. The level of brake aplication and when to apply the brakes is regulated by the control unit which detects when a wheel slips (applies brakes to that wheel which transfers power to the other wheel/wheels) or detects lateral acceration (g force) and yaw rate (turning) to calcuate if the vehicle is rolling or sliding to then apply braking force to the required wheels to bring it back under control.
Try driving any vehicle with esp and the sports wheels and you'll soon find out just how far you can now push these cars before you get into any serious trouble........it's bloody hard!

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Alex.

MB Tech
Sydney, Australia
Volvo 122S
W201 190D 2.5 manual
W202 C240
W203 C32