BMW M3 ABS

If you've seen one ABS, you've seen them all. Wrong! While all anti-lock braking systems do operate in the same basic manner, BMW's ABS is more precise and effective than most for three main reasons:

• BMW's four wheel-speed sensors are in constant contact with all four wheels, providing greater accuracy than systems that use just three sensors. Each sensor carries accurate feedback from a specific wheel independently. A three-sensor system provides an average wheel-speed figure for rear wheels. This average reading can be inaccurate when one side of the car is on dry pavement and the other is on ice.
• BMW's ABS pulsates 12 - 15 times per second while some competitors use less effective systems that pulsate as little as four times a second. The pulsation represents a cycle in which pressure is first released from a particular wheel that has begun to lock and then allowed to resume. The faster the cycle, the closer you are to achieving maximum braking efficiency.
• BMW's ABS also provides "yaw control," which keeps the car's back end from swinging to the side, by providing the proper balance between maximum braking and stability when one side of the car is on ice and the other is on dry pavement.
• BMW's state-of-the-art ABS works in harmony with other active safety elements to provide accurate steering, perfectly balanced handling and Automatic Stability Control + Traction, which ensures wheels always maintain optimum contact with the road. In fact, the wheel-speed sensors that detect and prevent brakes from locking are also used in BMW's ASC+T to detect and prevent wheels from spinning.

Limitations

While ABS can usually shorten braking distances on wet and icy roads, there are some limitations in other conditions. It may actually take longer to brake on loose stones or fresh snow because they cannot build up as wedge in front of the wheels as they would when the wheels are locked. Under any conditions, ABS should not be expected to perform miracles. But it does represent a major advance in safety.