1987 PORSCHE 944 tire pressure reset

ABS Brake System (Antilock brake system)
The ABS system represents a major
contribution to the enhancement of active
safety in your vehicle. This system prevents
the wheels from locking in a panic stop on
almost all road surfaces.
With ABS system in your vehicle, the
following areas are enhanced:
Full steerability , vehicle remains steerable
under all braking forces.
Good directional control , no swerving
caused by locking of wheels under braking
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
maneuverability of the car in emergency
situations, including panic braking in turns.
WARNING:
In spite of the improved handling afforded
by the ABS system, it still remains the
responsibility of the driver to adapt the
driving 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

justification for taking greater risks. Other vehicles not equipped with the ABS
system may not be able to maintain
control, especially on wet or poor road
surfaces and thus may be more likely to
impact you in the rear. To minimize that r
isk, use your ABS system to increase your ability to maneuver to avoid dangerous
situations and not merely to try to stop in
the shortest distance possible.
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
during 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 directional
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 comparable with rapid rhythmic braking. The proper operation of ABS is perceived by the driver as a pulsating brake pedal in conjunction with audible noise
and perhaps some vibration. 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 illumination of the central warning light, as well as the "ANTILOCK" light on the right hand
side of the instrument cluster.
If the ABS system becomes inoperative,
take your vehicle to your authorized dealer immediately.
Note
The control unit of the ABS brake system is
set for standard tire sizes. If non-standard
tires are fitted, the control unit may
misinterpret the speed of the vehicle, because of the variant data it receives from the sensors on the axles.
If the difference in rolling radius exceeds
approx. 17%, the control unit deactivates the
ABS system and the ABS warning lamp lights up.
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1 Set accelerate
2 Reset
3 Cancel

Automatic Speed Control
The automatic speed control allows you to
maintain a constant cruising speed of 25 mph
(40 km/h) or higher, without actuating the
accelerator pedal. Any manual operation,
such as accelerating, gearshifting or braking
can be done independent of the automatic
speed control. The spring loaded control lever
operating the automatic speed control is
located just below the wiper/ washer lever.
While driving with the automatic speed
control set at speeds above 25 mph (40
km/ h), do not bring shift lever into the
Neutral position as excessive engine rpm
will result.
To operate the automatic speed control Accelerate to the desired cruising speed, push lever toward instrument cluster (arrow 1) and
release. This sets the cruising speed and
stores it in a memory.
After a second or two, automatic speed control will take over and you can remove
your foot from the accelerator pedal. The set
cruising speed will be maintained
automatically.
WARNING
Do not use the cruise control when it may
be unsafe to keep the car at a constant
speed. For example, a constant speed may not be safe in heavy traffic, or on winding
or slippery roads. With the cruise control
system engaged, the engine speed will not
return to idle when removing the foot from
the accelerator pedal.
Please observe all local and national speed limits.

Passing: If you want to drive faster for a brief
moment, for example when passing another
vehicle, actuate the accelerator. When you
take your foot off the accelerator pedal, the
preset speed will automatically be resumed.
Gearshifting: When shifting gears, the
automatic speed control is only disengag
ed as long as the clutch pedal is depressed. The
preset speed will be resumed as soon as you
take your foot off the clutch pedal.
Braking and stopping: Whenever you apply
the brake or come to a stop, the automatic
speed control is disengaged. Move the lever
down (arrow 2), and the preset speed will be
resumed.

Switching system off: To switch off the
automatic speed control, move the lever
toward you (arrow 3). To resume the preset
speed, move the lever down (arrow 2).
To change the preset cruising speed
Increase preset speed:
Accelerate by depressing the accelerator pedal. When the desired speed is reached push lever toward instrument cluster (arrow 1) and take your foot off the accelerator pedal.
Now the new cruising speed is set and stored
in the memory. As an alternative, you can hold the lever in the front position (arrow 1), without depressing the accelerator pedal. The car will
accelerate on its own. When the desired
speed is reached, release the lever.
Decrease preset speed:
Apply the brake, which will disengage the automatic speed control. When the vehicle
has slowed down to the desired speed, push
lever toward instrument cluster (arrow 1) to
set the new cruising speed.
As an alternative, disengage the automatic
speed control by moving the lever toward you
(arrow 3). When the vehicle has slowed down
to the desired speed, push lever toward
instrument cluster (arrow 1) to register the
new cruising speed in the memory.
Note: When driving up a hill, if the engine
power is insufficient in a particular gear, the
speed control will be disengaged
automatically. Shift to a lower gear to avoid
stalling the engine.

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