2009 PORSCHE BOXSTER tire size

60
Operation, Safety
When the ignition is switched on the ABS warning
light will light up while the system is electronically
interrogated and goes o
ut when the engine is
started if the check is not yet complete.
If the ABS warning lamp fails to go out, this indi-
cates that ABS has been deactivated due to a
fault. If the warning lights in the instrument panel
and on-board computer light up while you are driv-
ing, this indicates that a fault has occurred. In both
cases, normal braking, as in vehicles without ABS,
is still retained.
The ABS system should, however, be examined at
an authorized Porsche dealer immediately to pre-
vent the occurrence of further faults.
f If the ABS system becomes inoperative, take
your vehicle to your authorized Porsche dealer
immediately.
Warning!
Risk of an accident, resulting in serious per-
sonal injury or death.
The control unit of the ABS brake system is
set for standard tire size. If non-standard
tires are installed, the control unit may mis-
interpret the speed of th e vehicle, because of
the variant data it rece ives from the sensors
on the axles.
f Use only tire makes and types tested by Porsche.
Clutch Pedal The clutch pedal must be depressed fully
before the starter will engage.
Warning!
Risk of an accident, resulting in serious per-
sonal injury or death.
f Always check the movement of the clutch ped-
al before driving and make sure that it is not
obstructed by a floor mat or any other object.
f Secure the floor mat to prevent it from sliding
into positions that could interfere with the safe
operation of your vehicle.
Your Porsche dealer will be glad to offer you
nonskid floor mats of the correct size.
To avoid damage to the clutch and transmis-
sion:
f Always depress the clutch pedal fully when
changing gears.
f Do not hold the car on a steep grade with the clutch pedal partially depressed.
Should the free travel of the clutch pedal suddenly
become larger, it could me an a malfunction of the
clutch.
f See your Porsche dealer for correction.
Warning light USA
Warning light Canada

Instruments, On-Board Computer, Warnings
147
TPM
Tire Pressure MonitoringfPlease see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.
The Tire Pressure Monitoring continuously
monitors tire pressure and tire temperature on all
four wheels and warns the driver when the tire
pressure is too low.
The display as well as the settings for the Tire
Pressure Monitoring take place on the on-board
computer.
However, you must still adjust the tire pressure on
the wheel. f
The driver is responsible for filling the tires
correctly and making the correct settings on
the on-board computer.
The Tire Pressure Monitoring offers the following
functions:
– Display of the actual ti re pressure while the
vehicle is in motion.
– Display of the deviation from the required pressure (refilling pressure).
– Display of currently set tire size and type.
– Tire pressure warnings in two stages.
Warning!
f Despite the advantages offered by the Tire
Pressure Monitoring, it is still the driver’s re-
sponsibility to update the corresponding set-
tings in the on-board computer and maintain
the pressure in the tires.
Low tire pressure reduces the road safety of
the vehicle and destroys the tire and wheel.
f When a flat tire has been displayed, immedi-
ately stop in a suitable place and check the
tires for damage. If necessary, remedy the
damage with a tire sealant.
f Do not by any means continue to drive with
damaged tires.
f Sealing the tire with tire sealant is only an
emergency repair, so you can drive to the next
authorized Porsche dealer. The maximum per-
mitted speed is 50 mph (80 km/h). f
Do not drive with tires whose tire pressure
drops again in a short period of time. In cases
of doubt, have tires checked by an authorized
Porsche dealer.
f Damaged tires must be immediately replaced
by an authorized Porsche dealer.
Tire repairs are not permissible under any
circumstances.
f If a fault occurs in the Tire Pressure Monitoring
(e.g. defective wheel tr ansmitter), contact an
authorized Porsche dealer immediately and
have the damage repaired.
The tire pressure will not be monitored at all or
will be monitored only partially by defective
Tire Pressure Monitoring.
f Tires lose air over time without a tire defect
being present. A tire pressure warning will then
appear in the on-board computer display.
Correct the tire pressure at the next oppor-
tunity.
f The Tire Pressure Monitoring gives a warning
about tire damage due to natural pressure loss
as well as about a gradual loss of pressure due
to foreign objects.
The Tire Pressure Mnitoring cannot warn you
about tire damage that occurs suddenly (e.g.
flat tire due to abrupt external effects).

Instruments, On-Board Computer, Warnings
149
The tire pressure to be corrected (refill pressure)
is indicated on the displayed wheel.
Example: If “ –1.5 psi (–0.1 bar)” is displayed,
1.5 psi (0.1 bar) must be added to this tire.
Note
The tire pressure menu can only be called up when
the vehicle is stationary.
Calling up the “Info pressure” display
fPush operating lever forward in order to switch
on the selection field.
f Select “TPM” with the operating lever.
f Push operating lever forward.
The display changes to the tire pressure menu.
f Select “Info pressure” with the operating lever.
f Push operating lever forward.
Note
After the ignition is switch ed on, it can take up to
approx. 1 minute before all tire pressures are
displayed. Dashes (“-.-”) appear instead of the tire
pressures. Tire type info in Tire pressure menu
Information about the currently set tires:
– Tire type: Summer tires, winter tires
– Tire size: 17, 18, 19 inch
“Info tires” shows the current tire settings.
Calling up the “Info tires” display
f
Push operating lever forward in order to switch
on the selection field.
f Select “TPM” with the operating lever.
f Push operating lever forward.
The display changes to the tire pressure menu. f
Select “Info tires” with the operating lever.
f Push operating lever forward.
Tire selection in the “Set” menu
f Push operating lever forward in order to switch
on the selection field.
f Select “TPM” with the operating lever.

Instruments, On-Board Computer, Warnings
151
fSelect “Continue” and push the operating lever
forward. f
Select the appropriate tire size (17, 18 or 19
inch) and push operating lever forwards. A dis-
play for confirming the selected tire size ap-
pears.
Note
This menu is displayed only if the tire pressures
are different for the approved tire sizes. f
Select “Continue” and push the operating lever
forward.

152
Instruments, On-Board Computer, Warnings
The tire selection has only been successfully
completed when the message “Process
complete” is displayed by the on-board computer.
f
Select arrow (Back) and push the operating
lever forward. The display returns to the tire
pressure menu.
The on-board computer additionally displays
the message “System learning”. Note
The message “Process aborted” appears if the
setting process is interrupted. All entries made up
to this point are lost, and the original settings
remain in effect.
Only if the message “Process complete” appears
after the settings have been made will the Tire
Pressure Monitoring re-learn the wheels.
f
Please see the chapter “SYSTEM LEARNING”
on Page 154.
Before fitting tires with sizes which are not stored
in the on-board computer, the missing information
should be supplemented in the on-board
computer.
f Please consult your authorized Porsche
dealer.
f Use only tires approved by Porsche.
The available items in the tire pressure menu
depend on the equipment of your vehicle. For this
reason it is possible that some of the items shown
here are not available on your on-board
computer’s display.
f Make sure that tire pressures correspond to
the on-board computer settings. Correct the
tire pressure if necessary.
f Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277. Tire pressure warnings
The tire pressure warning light on the instrument
panel and a corresponding message on the on-
board computer warn about loss of pressure in
two stages, depending on the amount of pressure
loss.
Driving with insufficient tire pressure reduces the
road safety of the vehicle
and destroys the tire and
wheel.
Stage 1 – Add air
The pressure in the tire is too low by 4 to 7 psi (0.3
to 0.5 bar).
f The tire pressure warning contains the
affected tire with the tire pressure to be added.
Correct the tire pressure at the next
opportunity.

Practical Tips, Emergency Service
225
Each tire, including the spare (if provided) should
be checked monthly when cold and inflated to the
inflation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire infla-
tion pressure label. (If your vehicle has tires of a
different size than the size indicated on the vehicle
placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for
those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring (TPM)
that illuminates a low tire pressure telltale when
one or more of your tires is significantly under-in-
flated. Accordingly, when the low tire pressure tell-
tale illuminates, you should stop and check your
tires as soon as possible, and inflate them to the
proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can
lead to tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
Please note that the TP M is not a substitute for
proper tire maintenance, and it is the driver’s re-
sponsibility to maintain correct tire pressure, even
if under-inflation has not reached the level to trig-
ger illumination of the TP M low tire pressure tell-
tale.
f On vehicles with tire pressure monitoring:
Please see the chapter “TPM TIRE PRESSURE
MONITORING” on Page 147.
When tires are warm, the tire pressure is
increased. f
Never let air out of hot tires.
This could cause the tire pressure to fall below
the prescribed value.
Insufficient tire filling pressure can cause tires to
overheat and thus be damaged – even invisibly.
Hidden tire damage is not eliminated by subse-
quently correcting the tire pressure.
Overloading
Danger!
Risk of damage to vehicle parts, loss of con-
trol and serious personal injury or death.
f Do not overload your vehicle. Be careful about
the roof load.
f If loading the vehicle also correct the tire pres-
sure. Tire pressure for loaded vehicle can be
found on the tire pressure plate and in the
chapter technical data.
f Never exceed the specified axle load.
Overloading can shorten the service life of the
tires and car, as well as lead to dangerous ve-
hicle reactions and long braking distances.
Damage due to overloading is not covered by the vehicle warranty.
f Please see the chapter “LOADING INFORMA-
TION” on Page 234.
f Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.
Example of a tire pressure plateTire pressure plateInformation on the tire pressure plate
A Seating capacity
Maximum number of vehicle occupants, inclu-
ding the driver.

226
Practical Tips, Emergency Service
B Vehicle load limit
Is the maximum total weight limit specified of
the load (passengers and cargo) for the vehi-
cle. This is the maximum weight of passengers
and cargo that can be loaded into the vehicle.
Please see the chapter “LOADING INFORMA-
TION” on Page 234.
C Tire size for the front axle Check with your authorized Porsche dealer
about the current release status.
D Recommended tire pre ssure for the front axle
These values are for cold tires (68 °F/20 °C).
E Tire size for the rear axle Check with your authorized Porsche dealer
about the current release status.
F Recommended tire pressure for the rear axle. These values are for cold tires (68 °F/20 °C).
G In vehicles with collapsible spare wheel: Size and tire pressure of the spare wheel.
Tire traction
Warning!
When driving on wet or slushy roads, a
wedge of water may build up between the
tires and the road. This phenomenon is
known as “hydroplane” and may cause par-
tial or complete loss of traction, vehicle
control or stopping ability.
f Reduce speed on wet surface to prevent this. Tire life Tire life depends on vari ous factors, i. e., road
surfaces, traffic and wea ther conditions, driving
habits, type of tires and tire care.
f Inspect your tires for wear and damage before
driving off. If you notice uneven or substantial
wear, wheels might need alignment or tires
should be balanced or replaced.
Tire wear The original equipment tires on your Porsche have
built-in tire wear indicato rs. They are molded into
the bottom of the tread grooves and will appear as
approximately 1/2 in. (12 mm) bands when the
tire tread depth is down to 1/16 of an in.
(1.6 mm).
When the indicators appear in two or more adja-
cent grooves, it is time to replace the tires. We
recommend, however, that you do not let the tires
wear down to this extent.
Worn tires cannot grip the road surface properly
and are even less effective on wet roads.
Snow tires lose their traction capability when their
tread depth falls below 5/32 in. (4 mm).
In the United States, state laws may govern the
minimum tread depth permissible. Follow all such
laws.

232
Practical Tips, Emergency Service
Example of InscriptionInscription on radial tireATire size
Example: P 295/30 ZR 19 100 Y
–P - The tire is designed for Passenger vehicle.
This information is not included on all tires.
– 295 - Indication of tire width in mm
– 30 - Indication of tire height to tire width ratio
in percent –
ZR - code letter for radial tires for speeds
above 150 mph / 240 km/h
There are currently no standards concerning
tire strength at speeds above 150 mph
(240 km/h).
– R - Belt type code letter for radial
– 19 - Indication of rim diameter in inches
– 100 - Load capacity coefficient
– Y - Speed code letter
– XL (Extra Load) - Tire with increased load rat-
ing
B TIN (Tire Identification Number)
Example: DOT xx xx xxxx xxxx
–DOT
The DOT symbol indicates that the tires com-
ply with the requirements of the US Depart-
ment of Transportation and provides informa-
tion about:
– first two-digit code means manufacturer’s iden- tification mark.
– second two-digit code means tire size.
– third four-digit code means tire type code.
– fourth four-digit code means date of manufac- ture.
If, for example, the last four numbers read
0208, the tire was produced in the 2nd week
of 2008.
C Tire ply composition and material
The number of layers in the tread and sidewalls
and their material composition.
D Maximum permissible inflation pressure
The maximum permissible cold inflation pressure
to which a tire can be inflated.
f Do not exceed the permissible inflation
pressure.