142
Instruments, On-Board Computer
A-Tire pressure
B-Tire temperature
C-Tire pressures for cold tires
D-Tire pressure for hot tires
E-Pressure increase as the result of temperature
increase
F-Pressure drop in faulty/leaking tiresPressure increase as the result of
temperature increase1. Required-pressure line
2. Warning stage 1
(from –4 to –7 psi (–0.3 bar to –0.5 bar))
3. Warning stage 2
At speeds above 100 mph (160 km/h):
(from –5 psi (–0.4 bar))4. Warning stage 2
At speeds below 100 mph (160 km/h):
(from –7 psi (–0.5 bar))
In accordance with physical principles, the air
pressure changes as the temperature changes.
The tire pressure increases or decreases by
around 1.5 psi (0.1 bar) for every 18 °F (10 °C)
change in temperature.
The Tire Pressure Monitoring takes this relation-
ship between tire pressure and temperature into
account.
Tire pressure specificationsInformation on tire pressure for public roads can
be found in this Owner's Manual in the Technical
Data chapter or on the tire-pressure plate in the
left door aperture.
These values apply to cold tires at 68 °F (20 °C)
ambient temperature.
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184
Practical Tips, Emergency Service
Tires/Wheels The original equipment tires and wheel rims on
your Porsche comply with all applicable Federal
Motor Vehicle Safety Standards.
For your safety remember the following:
– Wheel rims and wheel bolts are matched to fit
your Porsche.
– If you intend to use other than original equip-
ment wheels, be sure that they conform to
Porsche specifications for your model.
Only tires with the same make and with the
same specification code (e.g. “N0”, “N1”...)
can be mounted.
– The use of wheel rims and wheel bolts that do
not meet specifications of the original factory
installed equipment will affect the safe opera-
tion of your vehicle.
– Before you plan on exchanging wheels, or
snow tires already mounted on the wheel rims,
consult your authorized Porsche dealer. Your
dealer has the technical information necessary
to advise you which wheel rims and wheel bolts
are compatible with the original factory instal-
lations.
Danger!
Risk of loss of control and serious personal
injury or death.
fIf while driving, your vehicle experiences a
sudden vibration or ride disturbance, and/or
you suspect that possible damage to your tires
or vehicle has occurred, you should immedia-
tely reduce your speed without excessive use
of the brakes.
fStop the vehicle as soon as possible, and
inspect the tires.
If you cannot determine the cause for the
disturbance, have your vehicle towed to the
nearest Porsche or tire dealer to have your
vehicle or tire(s) inspected.
fContinuing to operate the vehicle without
correction could result in a loss of control and serious personal injury.
ExampleUniform Tire Quality GradingQuality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width.
All passenger car tires must conform to Federal
Safety Requirements in addition to these grades.
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