2005 PORSCHE 911 CARRERA winter tires

Controls, Instruments
139
Porsche Communication
Management (PCM) fRefer to the separate operating instructions
before putting the PCM into operation.
fPlease observe the chapter “LOAD SWITCH-
OFF AFTER 2 HOURS OR 7 DAYS” on
Page 233.
Warning!
There is a danger of accident if you set or op-
erate the on-board computer, radio, navi-
gation system, telephone or other equipment
when driving.
This could distract you from the traffic and
cause you to lose control of the vehicle re-
sulting in serious personal injury or death.
fOperate the components while driving only if
the traffic situation allows you to do so safely.
fCarry out any complicated operating or setting procedures only with the vehicle stationary.The reception conditions for the radio module inte-
grated in the PCM change continuously as you
drive. Interference from buildings, terrain and the
weather is unavoidable.
FM stereo reception is particularly susceptible to
varying reception conditions.
Electronic accessories should only be retrofitted
by a qualified specialist workshop.
Accessories which have not been tested and
approved by Porsche may impair radio reception.
NavigationWhen put into operation for the first time, a
distance of approx. 30 miles (50 km) must be
driven in order for the navigation system to
complete the process of fine calibration.
The same applies when the tires are changed (e.g.
summer/winter tires) or new tires fitted.
Full location accuracy is not yet achieved during
the fine-calibration process.
If the vehicle has been transported (e.g. ferry, car
train), the system may take a few minutes to deter-
mine the current location after it has been
switched on.
Serious tire slip (e.g. spinning wheels on snow)
may result in temporarily inaccurate navigation.
When the battery has been disconnected, it may
take up to 15 minutes before the navigation
system is operational again.

Practical Tips, Emergency Service
215
Tire care fAvoid damaging tires and wheel rims.
fIf you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
fCheck tires for uneven wear and damage
before driving off.
fRemove imbedded material.
fReplace worn or damaged tires immediately.
fKeep oil, fuel, brake fluid, etc. away from tires.
fReplace missing valve stem caps.
fKeep tires inflated correctly.
fWash tires when washing the vehicle. Also
clean inner side of wheels.
fDo not use abrasive cleaners when washing
the wheels.
fCheck wheel rims for corrosion.
fRemove road salt, if driving in winter.
Tire damage, puncture fCheck tires for imbedded material, cuts, punc-
tures, cracks and bulges (side wall) before driv-
ing off.
In case of tire damage, where it is uncertain wheth-
er there is a break in the ply with all its conse-
quences or tire damage caused by thermal or me-
chanical overloading due to loss of pressure or
any other prior damage, we recommend that the
tire be replaced for safety reasons.
If one faulty tire is replaced it should be noted that
the difference in tread depth on one axle must not
exceed 30%.
Handling inconsistencies may result.
fPerform a visual inspection if necessary.
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.

Practical Tips, Emergency Service
217
Wheel alignment, wheel balancing As a precaution, have wheels with summer tires
balanced in the spring, and those with mud and
snow tires before winter.
Unbalanced wheels may affect car handling and
tire life.
Only the specified weights may be used for wheel
balancing.
Self-adhesive weights must not come into contact
with cleaning agents, since they could drop off.
Uneven tread wear indicates wheel imbalance. In
this event, the vehicle should be checked at an au-
thorized Porsche dealer.
Warning!
If, during a journey, uneven running or vibra-
tions occur that could be caused by damage
to tires or the car, the speed must be re-
duced immediately, but without braking
sharply.
If you continue your trip without having the
cause of the fault remedied, you might lose
control of your vehicle which could cause se-
vere personal injury.
fStop the vehicle and check the tires.
fIf no cause for the fault can be found, drive
carefully to the nearest authorized Porsche dealer.
Removing and storing tires fAfter changing, adjust tire pressure and torque
wheel bolts diagonally to 94 ftlb (130 Nm).
Tires must always remain on the same side of
the vehicle.
When wheels are removed, the direction of
rotation and position of each wheel should be
marked.
Example
FR (front right), FL, RR and RL.
Wheels must always be fitted in accordance with
their marking.
The preception that tire durability and perform-
ance are immune to the effects of storage and
age is unfounded.
Chemical additives, which make the rubber elas-
tic, lose their effectiveness in the course of time
and the rubber becomes brittle and cracks.
Therefore, the tires should be inspected from
time to time. Note
Under no circumstances should tires older than 6
years be used on your Porsche.
The age of the tire can be obtained from the “DOT”
code number. If, for example, the last four num-
bers read 1204, then the tire was produced in the
12th week of 2004.
fStore tires in a cool and dry place.

218
Practical Tips, Emergency Service
Snow tires For a better grip on snow and ice, use radial M+S
tires with studs.
Check with your local Motor Vehicle Bureau for
possible restrictions.
Danger!
Risk of loss of control and damage to the
vehicle as well as serious personal injury or
death.
The standard tires profile and rubber mixture
are optimized for wet and dry driving condi-
tions, and may not prove favorable for snow
conditions.
fTherefore install M+S tires before driving in such conditions.
Before mounting snow tires, consult with
your Porsche dealer. He has the technical
information necessary to advise you on
wheel and tire compatibility.
Snow tires should have the same load capacity as
original equipment tires and should be mounted on
all four wheels.
Snow tires with studs should be run at moderate
speeds when new in order to give the studs time
to settle.
Danger!
Tires with badly worn treads and studs are
very dangerous and could cause accidents
resulting in serious personal injuries or
death.
fMake sure they are replaced immediately.
fDo not drive a vehicle equipped with snow tires
at prolonged high speed.
Snow tires do not have the same degree of
traction on dry, wet or snowfree roads as a
normal tire.
Furthermore, snow tires wear rapidly under
these conditions. Comply with all state and local laws
governing snow tire and tread depth require-
ments.
Danger!
Risk of accident and serious personal injury
or death due to excessive speed.
fAlways check the maximum speed rating on
the tire sidewall on any tire on the vehicle.
fNever exceed the maximum speed rating of the tires.
fFit winter tires to both axles well before the
cold season begins.
Your authorized Porsche dealer will be pleased
to advise you.
Maintenance note
We recommend fitting winter tires on the vehicle at
temperatures below 45°F (7°C ).
Winter tires lose their traction capability when their
tread depth falls below 5/32 in. (4 mm).

Practical Tips, Emergency Service
221
E Maximum Load rating
The maximum load in kilograms and pounds can
be carried by the tire. If you replace tires always
use a tire that has the same maximum load rating
as the factory installed tire.
FRadial
The identification indicates if the tire has radial
structure.
G Term of tubeless or tube tire
Identification for tubeless tires.Speed code letterThe speed code letter indicates the maximum per-
missible speed for the tire.
This code letter is shown on the tire sidewall.
T = up to 118 mph (190 km/h)
H = up to 131 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 186 mph (300 km/h)Tip on driving
Tires with a maximum speed rating that is lower
than the specified maximum vehicle speed may be
mounted only if they bear an M+S identification on
the tire sidewall.
fPlease note that in addition to the winter tires,
all-season and all-terrain tires are also subject
to speed limits and bear this identification.
Inscription on light alloy wheelsMaintenance note
fProtect the valve inserts against soiling with
valve caps.
Use only plastic valve caps.
Soiled valve inserts can cause a gradual loss
of air.
Note on operation
fThe rim width in inches A and the rim offset F
are visible from the outside. This information
can be found near the tire valve.
A-Rim width in inches
B- Rim-flange contour code letter
C- Symbol for drop-center rim
D- Rim diameter in inches
E-Double hump
F- Rim offset in mm

Technical Data
267
Tire Pressures for cold tiresSummer and winter tires
These tire filling pressures apply only to the tire makes and types approved by Porsche.
fPlease observe the chapter “TIRES/WHEELS” on Page 209. Tire and rim sizesExtensive tests are performed before specific tires and wheels are approved by Porsche. Your Porsche dealer has infor-
mation about approved tires and wheels and is happy to assist you.
If aftermarket tires and/or wheels are installed which are not approved by Porsche, the vehicle’s roadability and handling
characteristics might be impaired. Since Porsche has no data on such combinations, Porsche cannot stand behind the
safety or durability of these aftermarket combinations.
Snow chainsCan be mounted only on the rear wheels; maximum speed 30 mph (50 km/h).
Use only Porsche authorized fine-link cross-type or edge chains.
Snow chain clearance can be guaranteed only on the tire + rim combination marked**.
18 inch wheels front 36 psi (2.5 bar)
rear 44 psi (3.0 bar)
19 inch wheels, partially loaded front 33 psi (2.3 bar)
(up to 2 persons without luggage) rear 39 psi (2.7 bar)
19 inch wheels, fully loaded front 36 psi (2.5 bar)
(as of 2 persons with luggage) rear 44 psi (3.0 bar)

282
Index
TTachometer .................................................. 83
Tank ......................................... 188
, 189
, 268
Ventilation system ............................... 193
Technical data ............................................ 264
Telephone .................................................. 142
Temperature setting .................................... 120
Temperature, outside indicator....................... 87
Test stand, measurements ............................ 67
Theft protection ............................................ 18
Tiptronic .................................................... 145
Indicator............................................... 85
Tires ........................................... 16
, 209
, 266
Care .................................................. 209
Checking pressure .............................. 229
Inscription .......................................... 220
Loading information............................ 222
Pressure ............................... 5
, 212
, 267
Pressure plate .................................... 263
Sealant ......................................225, 226
Sidewall ............................................. 220
Size ................................................... 220
Tools ......................................................... 132
Towing ...................................... 150
, 259
, 260
Tow-starting ............................................... 150
Tracks ....................................................... 266
Transmission ......................................144, 265
Fluid...........................................195, 268
Trunk entrapment ....................................... 133
Turn signals..........................................83, 114
UUndercoating ......................................191
, 203
VValves ........................................................ 216
Vanity mirror ................................................. 41
Vehicle
Care .................................................. 198
Data................................................... 262
Identification label ............................... 262
Identification number ........................... 262
Putting into operation .......................... 239
Washing ............................................. 199
Ventilation .................................................. 120
Vents ................................................ 120
, 123
Viscosity, engine oil..................................... 184
WWarning lights and messages....................... 105
Washer
Fluid .......................................... 193
, 268
Lever ................................................. 115
Washing ..................................................... 199
Weights ...................................................... 269
Welcome Home Function ............................. 113
Wheel.................................. 16
, 204
, 209
, 266
Bolts .................................................. 228
Care .................................................. 209
Changing ............................................ 225
Checking pressure.............................. 229
Inscription .......................................... 220
Loading information............................. 222
Securing wheel bolts ............................. 19
Sidewall.............................................. 220
Size ................................................... 220
Tire pressure ......................... 5
, 212
, 267Tire pressure plate..............................263
Tire sealant................................ 225
, 226
Windows...................................... 28
, 156
, 203
Washer nozzles ...................................115
Washer system .................. 115
, 193
, 268
Windshield wiper/washer lever .....................115
Windshield wipers .............................. 115, 196
Replacing ...........................................196
Windstop ....................................................165
Winter operation
Battery ...............................................238
Coolant ..............................................179
Engine oil............................................180
Jumper cables ........................... 242, 243
Locks .................................................201
Seals..................................................204
Snow chains .......................................219
Tires ......................................... 218, 266
Washer fluid ........................................193
Wiper blades .......................................196
Wiper
Blades ................................................196
Rear ...................................................116