BMW x5 2000 Manual Do Utilizador

Index

Data

Technology

Repairs

Car care

Controls

Overview

119

Catalytic converter

Antilock Brake System (ABS)

Be sure to comply with the in-
structions above to prevent un-

burned fuel from reaching the catalytic
converter. Otherwise, the catalytic con-
verter could respond by overheating,
leading to serious damage.
Extreme temperatures occur at the cat-
alytic converter on this and every cata-
lyst-equipped vehicle. Heat shields are
installed adjacent to some sections of
the exhaust system. Never remove
these shields; do not apply undercoat-
ing to their surfaces. When driving,
standing at idle, and parking the vehi-
cle, take care to avoid contact between
the exhaust system and flammable ma-
terials (grass, hay, leaves, etc.). Such
contact could lead to a fire, resulting in
serious personal injury and property
damage.

The concept

ABS enhances active safety by helping
to prevent the wheels from locking un-
der braking. This is because: 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.

With ABS, you will achieve the shortest-
possible braking distances under all
given conditions (braking while driving
straight ahead or in curves, different
road surfaces).

ABS is designed to meet two essential
requirements during every brake appli-
cation:

To help provide vehicle stability.

To help retain steering and maneu-
vering capability on all types of road
surfaces (asphalt, cement, dirt, wet
surfaces, snow and 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).

To shorten the braking distance — espe-
cially on steep, poor road surfaces when
driving slowly straight ahead — the sys-
tem allows one or both front wheels to
lock for a short time. Nevertheless, the
vehicle still retains steering response
since this "poor road logic" is deacti-
vated again automatically as you steer.

If you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply maxi-
mum 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's closed-loop control
circuit cycles in fractions of a second.
A pulsation at the brake pedal, together
with the sounds associated with the
hydraulic controls, tells you that the
brake system is within its maximum
limit range and reminds you that you