BMW M COUPE, Руководство пользователя

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Index
Data
Te
chnolog
y
Repairs
Maintenance
Controls
Overview
Antilock Brake System (ABS)
The concept
ABS increases active safety by
preventing the wheels from locking
when braking. 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 straight-aways or in
curves, on the various road surfaces).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>
To help provide vehicle stability
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Assured ability to steer and maneuver
on the various road surfaces (asphalt,
concrete, dirt, wet conditions, snow
and ice).
Braking with ABS
The system is operative once the
vehicle exceeds a speed of approx.
6 mph (10 km/h). It is inactive once
again below approx. 4 mph (6 km/h).
Therefore, the wheels could theoreti-
cally tend to lock in the final phase of a
braking action, but this is insignificant in
actual practice.
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 closed-loop control circuit
cycles in fractions of a second. The
pulsation at the brake pedal, together
with sounds generated by the hydraulic
control system, indicate to you that the
vehicle is approaching its maximum
braking range. It is a reminder to you
that you must adapt the vehicle's road
speed to existing road conditions.
On road surfaces that have a loose
surface layer on a firm base with good
traction (on gravel, deep sand or snow,
for example), braking distances may be
longer than with locked wheels. This
also applies for driving with snow
chains. However, ABS continues to
provide enhanced vehicle stability and
steering response under these condi-
tions.