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57
Rollover Protection System The Rollover Protection System on the Cabriolet
consists of two supplemental safety bars that to-
gether with the front windshield frame help to cre-
ate occupant survival space in case of rollover. Be-
cause of the extreme and unpredictable forces
which can be encountered in a rollover, it is not
possible to guarantee that occupants will be pro-
tected from all contact with exterior objects or the
ground. However, the Rollover Protection System
is designed to maintain the occupant survival
space.
The Rollover Protection System is activated auto-
matically in the event of an accident or extreme
driving situation.
The protective devices are located behind each
rear seat and rapidly deploy within a fraction of a
second.
They can deploy under:
– Extreme tilting of the vehicle.
– Loss of ground contact (e.g. Going over the
crest of a hill at high speed).
Danger!
Risk of death or serious injury.
fDo not block area of supplemental safety bars
with objects.
In the event of a deployment event, such
objects could potentially prevent such deploy-
ment from occuring, or such objects could
impact the car occupants at high speed.
fDo not tamper with or work on wiring and or
components of Rollover Protection System.
fAll work regarding this system must be carried
out by your authorized Porsche dealer.
fCheck functions and periodic service intervals
according to maintenance schedule (see your
authorized Porsche dealer).
To avoid damage to the convertible top:
fIf the supplemental safety bars are extended
for any reason, do not open or close converti-ble top.Faults in the Rollover Protection System are indi-
cated by the airbag warning light in the instrument
panel.
Extension of the supplemental safety bars is no
longer ensured.
fSee your authorized Porsche dealer immedi-
ately and have the fault remedied.
Lowering the supplemental safety bars
after deployment fHave this work performed by an authorized
Porsche dealer.
Warning light
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58
Controls, Instruments
Parking Aids Parking assistantWhen the driver backs up, the parking assistant
system indicates the distance between the car
and a large obstacle behind it, by means of signal
tones.
Warning!
Risk of serious personal injury or death.
Parking assistant cannot detect small ob-
jects such as children and pets.
Despite use of the parking assistant system,
the driver is still responsible for taking due
care and assessing obstacles when backing
up.
fMake sure that no persons, especially small
children, animals or obstacles are within the maneuvring area.
The parking assistant system is activated auto-
matically when reverse gear is selected and the ig-
nition is on.
Note
Be aware that the parking assistant system is
not switched on if the car rolls backward without
reverse gear being engaged.
Ultrasound sensors
Sensors
Four ultrasound sensors in the rear bumper meas-
ure the distance to the closest obstacle.
– Range middle sensors around 60 in./150 cm
– Range outer sensors around 24 in./60 cm
Obstacles cannot be detected in the “blind” sen-
sor area (e.g. near the ground).
Note
The sensors must always be kept free of dust, ice
and snow in order to ensure that they are fully
functional.
Caution!
To avoid damaging the sensors:
fMaintain sufficient distance when cleaning with steam-jet units.
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59
Signal tones/function
When reverse gear is selected, the parking assist-
ant confirms that it is switched on by issuing a
short signal tone.
A detected obstacle is signalled by an intermit-
tent tone. The intervals decrease as the obstacle
is approached.
A continuous tone sounds when the distance be-
comes less than one foot. This continuous tone
can stop if the obstacle is approached closer than
one foot.
The radio volume should not be so loud as to
drown out the signal tones. Limits of ultrasonic measurement
The parking assistant system cannot detect:
– sound-absorbing obstacles (e.g. powder
snow),
– sound-reflecting obstacles (e.g. glass surfac-
es, flat painted surfaces)
– and very thin obstacles.
– Other ultrasound sources (e.g. pneumatic
brakes of other vehicles, jackhammers) can in-
terfere with detection of obstacles. Fault indication
The parking assistant system indicates a fault in
two ways:
– After reverse gear has been selected, the
short signal tone is followed by a continuous
tone of the same pitch:
This indicates that sensors are soiled or cov-
ered with ice.
– After reverse gear has been selected, the
short signal tone is followed by a continuous
tone with a much lower pitch:
This indicates a general system fault. Please
have the fault remedied at an authorized
Porsche dealer.
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Controls, Instruments
A- Control switch for door mirror adjustment Swivelling down mirror glass as a parking
aidfPlease observe the chapter “SEAT MEMORY”
on Page 36.
– When reverse gear is engaged, the mirror
glass on the passenger’s side swivels down
slightly to show the curb area. Preconditions
– Vehicle must be equipped with seat memory.
– Set the control switch A to “passenger’s side”.
– Reverse gear must be engaged.
Returning mirror glass to its original position
fDrive forwards with a speed of over 4 mph
(6 km/h) or
fSet the control switch A to “driver’s side”.
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61
Four-Wheel Drive With the four-wheel drive of the 911 Carrera 4 and
911 Carrera 4S, the engine power is variably dis-
tributed to the front and rear wheels.
Power distribution and wheel speed compensation
between the front and rear axles is realised with a
viscous multiple-disc clutch.
Distribution of the engine power is dependent
upon the wheel speed difference between the two
axles.
The viscous multiple-disc clutch always delivers
sufficient drive power to the front wheels (approx.
5% to 40%) to ensure optimum traction even on a
poor road surface.
In combination with the Porsche Stability Manage-
ment (PSM), four-wheel drive improves handling
and increases driving stability.
Warning!
The increased control that is provided should
not induce you to take greater risks with your
safety. The limits dictated by the laws of phy-
sics cannot be overcome, even with four-
wheel drive.
The risk of accidents due to inappropriate
speed cannot be reduced, even by four-
wheel drive.
The driver bears the responsibility for all dri-
ving maneuvers.
fAdapt your driving style to the prevailing road
and weather conditions.
fObey all traffic laws.
Dynamometer testing procedure Some U.S. states and Canadian provinces con-
duct emissions inspection/maintenance testing in-
volving the use of two-wheel dynamometer.
A two-wheeled dynamometer is a treadmill type
device upon which a single axle of the car, the dri-
ving axle of the vehicle, rotates to simulate vehicle
operation on the road while the vehicle remains
stationary.
Your 911 Carrera 4 or 911 Carrera 4S has a full-
time four-wheel drive system which cannot be
disabled. Severe damage to the powertrain can
result if tested on a two-wheel dynamometer.
Warning!
To avoid severe powertrain damage and a
possible unexpected movement of the vehic-
le.
fYour 911 Carrera 4 or 911 Carrera 4S vehicle
must never be tested on a two-wheel dynamo-
meter.
fAdvise the emission station of this warning be-fore testing the vehicle.
Power measurement
Power measurements on dynamometers are not
approved by Porsche.
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Controls, Instruments
Brake tests Brake tests must be performed only on plate-type
test stands or roller test stands.
The following limit values must not be exceeded
on roller test stands:
– Testing speed 5 mph (8 km/h)
– Test duration 20 seconds Handbrake tests Handbrake tests on the roller test stand must be
performed only with the ignition switched off. Balancing wheels on the vehicle During finish balancing of the wheels, the vehicle
must be hoisted and all the wheels able to rotate
freely. Towing fPlease observe the chapter “TOWING” on
Page 281.
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63
Retractable Rear SpoilerThe rear spoiler improves driving stability,
especially at higher speeds.
Warning!
Risk of accident. If the rear spoiler cannot be
extended, driving stability will be adversely
affected by increased rear axle lift, which
could lead to loss of control.
fAdapt your driving style and speed to the
changed driving behaviour.
fHave the fault remedied at an authorized
Porsche dealer.
Risk of injury during manual retraction or
extension of the rear spoiler with the vehicle
stationary.
fMake sure that no persons or objects are
within the range of movement of the rear
spoiler.
Risk of damage from pushing the vehicle by
the spoiler.
fDo not push the vehicle at the spoiler.
Automatic modeThe limits for automatic extension and retraction
of the spoiler depend on various circumstances
(e.g. driving speed, engine compartment temper-
ature).
Engine compartment temperature
under 122°F/55°C
Spoiler extends at 75 mph/120 km/h and
retracts at 37 mph/60 km/h.
Engine compartment temperature
over 140°F/60°C
Spoiler extends at 50 mph/80 km/h and retracts
at 19 mph/30 km/h.
If automatic control fails, a warning message is
displayed by the on-board computer.
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64
Controls, Instruments When the ignition is on, the rear spoiler can be
extended and retracted manually using the button
in the center console.
Extending
fPress button briefly.
The spoiler extends to its final position.
The light-emitting diode in the button lights up.Retracting a manually extended rear spoiler
fat speeds between 0 and 20 mph
(0 and 30 km/h)
Press and hold button until the rear spoiler has
reached its final position.
The light-emitting diode in the button goes out.
The rear spoiler changes to automatic mode.
fat speeds between 20 and 60 mph
(30 and 100 km/h)
Press button briefly.
The rear spoiler retracts, the light-emitting
diode in the button goes out.
The rear spoiler changes to automatic mode.
fat speeds over 60 mph (100 km/h)
Press button briefly.
The rear spoiler remains extended, the light-
emitting diode in the button goes out.
The rear spoiler changes to automatic mode.Manual control