
62
Operation, Safety When the ignition is switched on the ABS warning 
light will light up while the system is electronically 
interrogated and goes out 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. 
fIf 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 the vehicle, because of 
the variant data it receives from the sensors 
on the axles.
fUse 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. 
fAlways 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. 
fSecure 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: 
fAlways depress the clutch pedal fully when 
changing gears. 
fDo 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 mean a malfunction of the 
clutch. 
fSee your Porsche dealer for correction. 
Warning light USA
Warning light Canada 

Operation, Safety
63
Porsche Traction Management 
(PTM)With PTM, the engine power is variably distributed 
to the front and rear wheels.
Power distribution between the front and rear ax-
les is performed by a map-conrolled multiple-disc 
clutch. 
Distribution of the engine power also depends on 
the difference in wheel speed between the two ax-
les. 
The multiple-disc clutch always delivers sufficient 
drive power to the front wheels to ensure optimum 
propulsion even on an unfavorable road surface.
In combination with the Porsche Stability Manage-
ment (PSM), the PTM ensures optimum handling 
and high 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 PTM.
The risk of accidents due to inappropriate 
speed cannot be reduced, even by PTM.
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 vehicle 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 dy-
namometer. 
 Warning!
Risk of severe powertrain damage and a pos-
sible unexpected movement of the vehicle.
fDo not test your vehicle on a two-wheel dyna-
mometer.
fAdvise the emission station of this warning be-fore testing the vehicle. 
Brake testsBrake tests must be performed only on plate-type 
test stands or roller test stands. 
The ignition must be off.
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 only 
be carried out 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 see the chapter “TOWING” on 
Page 280.Wheels/TiresThe PTM control unit is adapted to the approved 
tire sizes. The use of non-approved tire sizes may 
lead to deviations in wheel speeds and it may influ-
ence handling or result in the PTM switching off. 

Instruments, On-Board Computer, Warnings
143
TPM
Tire Pressure MonitoringfPlease see the chapter “TIRE PRESSURES FOR 
COLD TIRES (68 °F / 20 °C)” on Page 289.
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.fThe 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 tire 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!
fDespite 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.
fWhen 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.
fDo not by any means continue to drive with 
damaged tires.
fSealing 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).fDo 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.
fDamaged tires must be immediately replaced 
by an authorized Porsche dealer.
Tire repairs are not permissible under any 
circumstances.
fIf a fault occurs in the Tire Pressure Monitoring 
(e.g. defective wheel transmitter), 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.
fTires 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.
fThe 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
145
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.
fSelect “TPM” with the operating lever.
fPush operating lever forward. 
The display changes to the tire pressure menu.
fSelect “Info pressure” with the operating lever.
fPush operating lever forward.
Note
After the ignition is switched 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: 18, 19 inch
“Info tires” shows the current tire settings.
Calling up the “Info tires” display
fPush operating lever forward in order to switch 
on the selection field.
fSelect “TPM” with the operating lever.
fPush operating lever forward. 
The display changes to the tire pressure menu.fSelect “Info tires” with the operating lever.
fPush operating lever forward.
Tire selection in the “Set” menu
fPush operating lever forward in order to switch 
on the selection field.
fSelect “TPM” with the operating lever. 

146
Instruments, On-Board Computer, Warnings fPush operating lever forward. 
The display changes to the tire pressure menu.fSelect “Set” with the operating lever.fPush the operating lever forward.
fSelect desired tire type: 
summer or winter.
fPush operating lever forward.
A display for confirming the selected type of 
tire appears. 

238
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 246.
C Tire size for the front axle
Check with your authorized Porsche dealer 
about the current release status.
D Recommended tire pressure 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. 
fReduce speed on wet surface to prevent this. Tire life Tire life depends on various factors, i. e., road 
surfaces, traffic and weather conditions, driving 
habits, type of tires and tire care. 
fInspect 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 indicators. 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.  

240
Practical Tips, Emergency Service
 Danger!
Risk of serious personal injury or death. 
Driving the vehicle with low tire pressure 
increases risk of a tire failure and resulting 
loss of control. Furthermore, low tire pres-
sure increases rate of wear of the affected 
tires.
fCheck tires – including sidewalls – regularly for 
foreign bodies, nicks, cuts, cracks and bulges.
fAfter driving off road, examine tires for signs 
of damage such as cuts, tears, bulges or for-
eign objects stuck in the tread. Replace a dam-
aged tire if necessary.
fCross curb edges slowly and at right angles if 
possible. 
Avoid driving over steep or sharp curbs.
fIn cases of doubt, have the wheel (particularly 
the inner side) checked by an authorized Porsche dealer.
Tire replacements If in doubt, contact your Porsche dealer.
Use only tire makes and types approved by 
Porsche. 
If you do not use a Porsche recommended 
replacement tire, make sure that you 
purchase your new tires from a reputable tire 
dealer and that the dealer complies with all 
manufacturers warnings for those tires. 
Only tires with the same make and with the 
same specification code (e.g. “N0”, “N1”...) 
can be mounted. 
Before mounting new tires, check with your 
Porsche dealer about the current release 
status. 
Use tires with “ZR” quality standards. There 
are currently no standards concerning tire 
strength at speeds above 150 mph (240 km/h). 
Tires should be replaced no less than on one axle 
at the time. 
Only tires of the same make and type must be 
used. Mixed tires are not permissible. 
Initially, new tires do not have their full traction. 
You should therefore drive at moderate speeds 
during the first 60 - 120 miles (100 - 200 km). If new tires are installed only on one axle, a notice-
able change in handling occurs due to the different 
tread depth of the other tires. 
This happens especially if only rear tires are re-
placed. However, this condition disappears as the 
new tires are broken in. 
fPlease adjust your driving style accordingly.
Installation of new tires should only be done by a 
qualified tire technician. 
Valves 
Rubber valve stems must be replaced every time 
a tire is replaced.
For metal valves, the installation and replacement 
instructions must be observed.
fUse only genuine Porsche metal valves.
fProtect the valve inserts against soiling with 
valve caps.
Soiled valve inserts can cause a gradual loss 
of air.
fUse only plastic valve caps. 

244
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 
0204, the tire was produced in the 2nd week 
of 2004.
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.
fDo not exceed the permissible inflation 
pressure.