Owner's Manual for the vehicle. With a quick reference ... - E38.org

Antilock Brake System (ABS)
125n
The concept
ABS enhances active safety by helping
to prevent the wheels from locking during
brake applications. The reason:
Locked wheels are dangerous. When
the front wheels slide, the driver loses
steering control over the vehicle. Traction
loss at the rear wheels can cause
the rear end to break into an uncontrolled
skid.
The system can achieve the shortest
braking distances possible under most
conditions (on straights and in curves,
on asphalt, ice, wet road surfaces, etc.).
ABS is designed to meet two essential
requirements during every brake application:
> To help provide vehicle stability
> To help maintain steering control and
maneuverability – on all types of road
surfaces (asphalt, concrete, mud, wet
pavement, snow, ice).
Braking with ABS
The system becomes operative once
the vehicle exceeds a speed of approx.
6 mph (10 km/h). The ABS is deactivated
whenever the vehicle's speed drops
back below approx. 4 mph (6 km/h). This
means that the wheels can lock in the final
phase of a panic stop – a factor of no
significance in actual use.
If you are in a situation which requires
full braking, you will exploit the full benefits
of the ABS system if you apply maximum
brake pressure ("panic stop").
Since the vehicle maintains steering responsiveness,
you can avoid possible
obstacles with a minimum of steering effort,
despite the full brake application.
The ABS system closed-loop control circuit
cycles in fractions of a second.
A pulsation at the brake pedal indicates
to the driver that ABS is active, that is,
that the vehicle is within its maximum
braking range. In addition, a pulsation – a
result of the control function cycles – indicates
to the driver that vehicle speed
should be reduced to adapt to road surface
conditions when there is reduced
traction and grip between tires and road
surface (slippery road surface).
Always depress the brake pedal with
constant pressure. Keep the brake pedal
down. Do not pump the brakes.
In driving conditions where there is a
loose upper surface together with a
subsurface which provides better traction
(on gravel or snow, for instance), or
with snow chains, the braking distance
may also be longer than when the
wheels are locked. However, ABS continues
to provide enhanced vehicle stability
and steering response under
these conditions.
Information for your safety
Not even ABS can suspend the laws of
physics. ABS alone cannot prevent accidents
when the brakes are applied
without an adequate safety interval between
vehicles, if the car is driven at an
excessive rate of speed in curves, or if
aquaplaning occurs. Responsibility for
these types of situations remains in the
hands (and at the feet) of the driver. You
should never allow the added safety of
ABS to lull you into a false sense of security,
or mislead you into taking increased
risks that could affect your own
safety and that of others.
Do not make any modifications to
the ABS system.
Service procedures on ABS are to be
performed by authorized technicians
only.<
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