beautypg.com

Antilock brake system (abs), Antilock brake system, Abs) – BMW 01 41 0 155 307 User Manual

Page 116: Catalytic converter antilock brake system (abs)

background image

116

n

Catalytic converter

Antilock Brake System (ABS)

Be sure to observe the instruc-
tions above to prevent unburned

fuel from reaching the catalytic
converter, otherwise, the catalytic
converter could overheat and be
damaged.
High temperatures occur in any vehicle
equipped with a catalytic converter.
Heat shields are installed adjacent to
some sections of the exhaust system.
Never remove these shields; do not
apply undercoating to their surfaces.
When driving, standing at idle, and
parking the vehicle, take care to avoid
contact between the exhaust system
and flammable materials (grass, hay,
leaves etc.). Such contact could lead to
a fire, resulting in personal injury and
property damage.

<

The concept

ABS enhances active driving safety by
helping to prevent the wheels from
locking under braking. The reason:
locked wheels are dangerous. When the
front wheels slide, the driver loses
steering control over the vehicle. Trac-
tion loss at the rear wheels can cause
the rear end to break into an uncon-
trolled skid.

The system can achieve the shortest
braking distances possible under most
conditions (on straight-aways and in
curves, on asphalt, ice, wet road
surfaces, etc.).

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

>

To help provide vehicle stability.

>

Assured ability to steer and
maneuver – on the various road
surfaces (asphalt, concrete, dirt,
wet conditions, snow, ice).

The system can achieve the shortest
braking distances possible under most
conditions (on straight-away and in
curves, on asphalt, ice, wet road
surfaces, etc.).

Braking with ABS

The system is operative once the
vehicle exceeds a speed of approx.
6 mph (10 km/h). It is deactivated once
again 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 that 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
nevertheless avoid possible obstacles
with a minimum of steering effort.

The ABS closed-loop control circuit
cycles in fractions of a second. A pulsa-
tion 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
should adapt road speed to the road
conditions.

On road surfaces that have a loose
surface layer on a firm base with good
traction (on gravel or snow, for
example), or when snow chains are
mounted, braking distances may be
longer than with locked wheels.

Online Edition for Part No. 01 41 0 155 307 - © 09/00 BMW AG