Porsche 928 GT1991, Руководство пользователя

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ABS brake system
(Antilock brake system)
The ABS system represents a major con-
tribution to the enhancement of active safety
in your vehicle. This system prevents the
wheels from locking in a panic stop on al-
most all road surfaces.
With ABS system in your vehicle, the fol-
lowing areas are enhanced:
Full steerability, vehicle remains steera-
ble under all braking forces.
Good directional control, no swerving
caused by locking of wheels under brak-
ing conditions.
Excellent stopping distance, stopping
distances are usually reduced because
controlled braking is maximized.
Prevention of wheel lock up, no brake-
induced sliding and thus no localized tire
wear from emergency braking.
The crucial advantage of ABS system over a
conventional brake system is in the area of
maintaining directional control and man-
euverability of the car in emergency situa-
tions, including panic braking in turns.
WARNING:
In spite of the improved handling afforded
by the ABS system, it still remains the re-
sponsibility of the driver to adapt the driv-
ing style to the prevailing road and weather
conditions, as well as, obeying traffic laws.
In no case, should the higher degree of
safety offered by ABS be regarded as a jus-
tification for taking greater risks. Other veh-
icles not equipped with the ABS system
may not be able to maintain control, espe-
cially on wet or poor road surfaces and
thus may be more likely to impact you in
the rear. To minimize that risk, use your ABS
system to increase your ability to maneuver
to avoid dangerous situations and not
merely to try to stop in the shortest dis-
tance possible. I
Driving with the ABS system
A wheel speed sensor is fitted to each of the
four wheels. If wheel slippage of either of the
front wheels or the rear wheels is sensed dur-
ing braking, the brake pressure is adjusted
automatically until the wheel no longer slips.
The brake pressure is regulated for each
front wheel individually and for both rear
wheels together.
On a road surface which is slippery on only
one side, the rear wheel which is braking on
the slippery surface determines the brake
pressure which will be applied equally to
both rear wheels. This ensures that direc-
tional stability is maintained. However, if
braking force approaches the wheel locking-
up point for all wheels (panic braking) the
ABS system will intervene in a way compara-
ble with rapid rythmic braking. The proper
operation of ABS is perceived by the driver
as a pulsating brake pedal in conjunction
with audible noise and perhaps some vibra-
tion. The driver is thereby warned to reduce
vehicle speed appropriate for the prevailing
road conditions.
If your ABS system should ever malfunction,
the ABS system is automatically switched
off, but the normal brake system, without
ABS, would remain fully operational. Such a
malfunction would be indicated by the illumi-
nation of the "ANTILOCK" light accom-
panied by the fault message in the informa-
tion system display.
If the ABS system becomes inoperative,
take your vehicle to your authorized
dealer immediately.
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