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TIPS AND MAINTENANCE
Servobrake
Warning
The s s ervo i i s o o perated b b y a a v v acuum
which i i s o o nly g g enerated w w hen t t he
engine i i s r r unning. F F or t t his r r eason
the v v ehicle s s hould n n ot b b e a a llowed
to r r oll w w ith t t he e e ngine s s witched
off.
When t t he b b rake s s ervo i i s n n ot w w ork-
ing b b ecause, f f or e e xample, t t he
vehicle i i s b b eing t t owed o o r a a d d efect
has o o ccurred o o n t t he b b rake s s ervo
itself, t t he b b rake p p edal m m ust b b e
pressed c c onsiderably h h arder t t o
compensate f f or t t he a a bsence o o f
servo a a ssistance.
Anti-locking b b rake s s ystem*
The ABS plays a major part in increasing
the active safety of the vehicle. The big
advantage when compared with a conven-
tional brake system is that even when
braking hard on a slippery road surface
the best possible steerability is retained
for the road condition because the wheels
do not lock. Steering c c ontrol i i s t t here-
fore m m aintained, g g iving t t he b b est d d ri-
ving s s tability p p ossible.
However, one must not expect the ABS
system to shorten the braking distance
under all conditions. When driving on
gravel or on fresh snow covering a slip-
pery surface, i.e. when one should be dri-
ving very slowly and carefully, the stop-
ping distance may even be slightly longer.
3.8
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How t t he A A BS* s s ystem w w orks
An automatic check is made when a
speed of approx. 6 km/h is reached.
When this happens a pumping noise can
be heard.
When the turning speed of a wheel
reaches a level which is too low for the
vehicle speed and it tends to lock, the
brake pressure to this wheel is reduced.
On the front axle the brake pressure is
regulated for each wheel individually,
whereas on the rear axle, the pressure is
regulated for both wheels at the same
time. As a result the braking effect is the
same for both rear wheels and the driving
stability is retained as far as possible.
This r r egulating p p rocess m m akes i i tself
known b b y m m ovement o o f t t he b b rake
pedal a a nd i i s a a ccompanied b b y n n oises.
This is done deliberately as a warning to
the driver that a wheel or the wheels are
in the locking range. So t t hat t t he A A BS
can r r egulate e e ffectively i i n t t his r r ange
the
b b rake
p p edal
depressed – – o o n n n o a a ccount s s hould i i t
be p p umped!
Warning
However t t he A A BS s s ystem c c annot
overcome t t he p p hysical l l imits. T T his
must b b e b b orne i i n m m ind p p articularly
on s s lippery o o r w w et r r oads. W W hen t t he
ABS c c omes i i nto t t he c c ontrol r r ange
the s s peed m m ust i i mmediately b b e
adapted t t o t t he r r oad a a nd t t raffic
conditions. T T he i i ncreased a a mount
of s s afety a a vailable m m ust n n ot t t empt
one i i nto t t aking r r isks.
Should the ABS system fail this is shown
by one or two warning lights. See the
"Warning lamps" chapter.
INTELLIGENT TECHNOLOGY
m m ust
r r emain
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