Antilock brake system (abs), Antilock brake system, Abs) – BMW 2006 bmw 325i User Manual
Page 118: Catalytic converter antilock brake system (abs)
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Catalytic converter
Antilock Brake System (ABS)
Be sure to comply with the
instructions above to prevent
unburned fuel from reaching the cata-
lytic convertor. If you do not, the cata-
lytic converter could respond by
overheating, leading to serious
damage.
Extreme temperatures occur at the
catalytic converter on this and every
catalyst-equipped vehicle. Heat shields
are installed adjacent to some sections
of the exhaust system. Never remove
these shields; do not apply under-
coating to their surfaces. When driving,
standing at idle, and parking the
vehicle, take extra care to avoid contact
between the exhaust system and flam-
mable materials (grass, hay, leaves,
etc.). Such contact could lead to a fire,
resulting in serious personal injury and
property damage.
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The concept
ABS enhances active safety by helping
to prevent the wheels from locking
under 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.
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
>
To help maintain steering control and
maneuverability – on all types of road
surfaces (asphalt, concrete, mud, wet
road surfaces, snow, ice).
Braking with ABS
The system becomes operative once
the vehicle exceeds a speed of approx.
6 mph (10 km/h). Below approx. 4 mph
(6 km/h), it is once again deactivated.
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 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, 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.
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 cannot prevent the
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