BMW 840Ci, Руководство пользователя

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128
Driving with ABS
After the engine has been started, the
yellow ABS warning light on the
instrument panel goes out.
The ABS system itself becomes oper-
ational above a road speed of app.
8km/h (5 mile/h). If the car's speed
drops below app. 3km/h (2 mile/h),
the ABS ceases to take effect, so that
in the very last phase of a brake appli-
cation the wheels could theoretically
tend to lock, but in practice this is not
critical
The ABS regulation cycle takes place
within fractions of a second. The brake
pedal pulsates to warn the driver that
the ABS is active and therefore that
the car is reaching the adhesion limit.
In addition a chattering noise is heard
– caused by the pressure regulating
action – to remind the driver that the
tyres' grip on the road is decreasing
(slippery surfaces) and that the car's
speed may therefore need to be
reduced accordingly.
a
If the road surface consists of
loose material on a firm underlayer, for
instance stone chippings or powdery
snow, the car's braking distance may
sometimes actually be longer than if
the wheels were to lock.
The same applies if snow chains are
fitted. However, the advantages of
greater stability and the ability to steer
while braking are still available to the
driver.
To ensure that the ABS system always
remains fully operational it must never
be modified in any way, and all work
on the ABS should be entrusted only
to skilled, authorized personnel.
c
ABS may not function at maximum
efficiency if tyres of different sizes are
fitted (e.g. winter tyres/spare wheel);
in such cases, revert to the correct
wheels and tyres as soon as possible.
Any malfunction is shown by the yel-
low ABS warning light on the instru-
ment panel coming on. The brake
system continues to work normally as
on a vehicle without ABS, but should
none the less be examined without
delay by BMW Service. Additional
faults to the brake system could
otherwise occur without being readily
apparent.
ABS
Online Edition for Part-No. 01 41 9 790 191 - © 12/98 BMW AG