
60
Operation, Safety Readiness for operation
PSM is switched on automatically every time you
start the engine.
PSM should always be switched on during
“normal” driving.
However, it may make sense to switch off PSM
temporarily in exceptional situations, for example:
– On a loose surface or in deep snow,
– when “rocking the vehicle free” and
– when using snow chains.
Switching off PSMPSM can be switched off in 2 stages:
– Stage 1 SC OFF:
Switch off Stability Control (SC).
– Stage 2 SC+TC OFF:
Also switch off Traction Control (TC).
Danger!
There is a risk of accident due to loss of
control of the vehicle. There is no stabilizing
brake control in either switch-off stages
(even when the brakes are used).
fPSM should always be switched on during
“normal” driving. This particularly applies in wet conditions.
Switching off Stability Control (SC)Precondition:
The light-emitting diode in the SC+TC OFF button
must be off.
fPress SC OFF button.
Stability Control is switched off after a short
delay.
The light-emitting diode in the button is lit up.
When the system is switched off, the multi-
functional PSM light on the instrument panel
is lit and the message “SC OFF” appears
continuously on the on-board computer.
An acoustic signal also sounds.
– When Stability Control is switched off, sportier
Traction Control is activated.
– Brake control is deactivated.
– The ABS remains active.Switching Stability Control (SC) back onfPress SC OFF button.
Stability Control is switched on after a short
delay.
The light-emitting diode in the button and the
multi-functional PSM light on the instrument
panel go out.
The on-board computer shows a message.
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192
Practical Tips, Emergency Service
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 snow tires on the vehicle at
temperatures below 45 °F (7 °C) since the driving
performance of summer tires is reduced at low
temperatures. Summer tires may be permanently
damaged at extremely low temperatures.
Winter tires lose their traction capability when their
tread depth falls below 5/32 in. (4 mm).
Snow chains
Caution!
Risk of damage to body, axle or brake
components.
fFit snow chains only to the rear wheels, and
only with the tire/rim combination listed in the
Technical Data.
To ensure adequate clearance between chain
and body, Porsche recommends only the use
of fine-link chains such as those approved by
Porsche.
fFollow instructions issued by the supplier of the chains.
In order to mount snow chains the vehicle must be
jacked up at the rear.
Different states and countries have varying statu-
tory requirements regarding maximum speed.
Check with local authorities for possible restric-
tions.
fRemove chains as soon as the roads are free
of ice and snow.
Tire designations Due to new speed and load ratings for radial tires,
new designations have come into force for snow
tires for your Porsche.
The designation to be used for ZR tires is e.g.,
265/40 ZR 18 (Z = code letter for radial tires for
speeds above 150 mph / 240 km/h).
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238
Technical Data
Tires, Rims, Tracks
Tire Rim Rim offset Track
Summer tiresfront 235/35 ZR 19 (87Y) 8.5 J x 19 H2 53 mm 58.9 in./1497 mm
911 GT3 rear 305/30 ZR 19 (102Y) XL 12 J x 19 H2 63 mm 60.0 in./1524 mm
Snow tiresfront 235/35 R 19 87V M+S 8.5 J x 19 H2 53 mm
911 GT3 rear 295/30 R 19 100V XL M+S* 11 J x 19 H2 67 mm
The load capacity coefficient (e.g. “87”) and maximum speed code letter (e.g. “Y”) are minimum requirements.
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*.
Tire and rim sizesExtensive tests are performed before specific tires and wheels are approved by Porsche. Your Porsche dealer has informa-
tion 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 driveability, stability while
in motion 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.
Danger!
Installation of sizes not authorized by
Porsche may have a dangerous effect on
the driving stability and could result in
severe personal injury or death.
fBefore mounting new tires, check with your Porsche dealer about the current release status.
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248
Index Seat
Adaptive sports seat ............................. 34
Adjustment ........................................... 33
Heating ................................................ 36
Position................................................ 33
Sports bucket seat............................... 35
Sports seat .......................................... 34
Service ...................................................... 124
Service brake ................................................. 6
SET Basic setting on on-board computer ...... 145
Shifting gears
Manual transmission............................ 155
Side lights, front ......................................... 227
Side marker light .................................. 73, 226
Side vents .................................................. 101
Snow chains ............................................... 192
Snow tires.................................................. 191
Socket ....................................................... 207
Spare key .................................................... 18
Speed code letter ....................................... 193
Speed control............................................... 79
Automatic............................................. 78
Indicator light...................................... 108
Speed limit ......................................... 120, 193
Speedometer ............................................. 110
Sport button ................................................. 62
Sport Chrono Plus package
CHRONO stopwatch............................ 127
Sport mode .................................................. 62
Sport tires...................................................... 5
Sports bucket seat ....................................... 35
Sports seat .................................................. 34
Stability Control (SC)..................................... 60
Stability management system (PSM) ............... 59Starter switch ............................................... 67
Starting ........................................................ 68
Starting engine ............................................. 70
Steam cleaners .......................................... 174
Steering column
Locking ................................................ 68
Steering lock ................................................ 67
Steering wheel
Adjustment ........................................... 36
Lock .................................................... 68
Stopping engine............................................ 71
Stopwatch .................................................. 127
Storage options ............................................ 83
Storage possibilities ...................................... 83
Storing your Porsche.................................. 181
Sun visors .................................................... 37
Suspension management............................... 63
Suspension setup ....................................... 241
TTachometer ................................................ 111
Tail light ..................................................... 227
Tank .......................................... 165, 166, 239
Ventilation system ............................... 167
Technical data ............................................ 236
TEL Telephone information .......................... 124
Telephone .................................................... 91
Temperature setting................................ 98, 99
Temperature, outside indicator .................... 114
Test stand
Measurements ...................................... 61
Theft protection ............................................ 17Tire
Care...................................................188
Damage .............................................188
Designations .......................................192
Pressure plate ....................................186
Replacements .....................................189
Traction..............................................187
Wear ..................................................187
Tire filling compressor ...................................87
Tire pressure
Compressor..........................................87
Tire pressure monitoring
Warning light .......................................141
Wheels ...............................................190
Tire pressure monitoring (TPM) ....................134
Tires ............................................13, 184, 238
Care...................................................184
Checking pressure ..............................203
Inscription...........................................193
Loading information .............................195
New tires ..............................................13
Pressure.....................................185, 237
Pressure monitoring............................134
Pressure plate ....................................235
Removing and storing ..........................191
Sealant .................................87, 203, 204
Sidewall ..............................................193
Size ...................................................193
Snow tires ..........................................191
Sport......................................................5
Tool kit .........................................................87
Tools ...........................................................87
Towing ...............................................230, 231
Towing hook ...............................................230
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250
Index Windows .................................................... 177
Anti-crushing protection ......................... 29
Care .................................................. 177
Opening/Closing ................................... 29
Washer nozzles .................................... 76
Washer system ..................... 76, 170, 239
Windshield
Washer nozzles .................................... 76
Wiper blades, changing ....................... 173
Wiper/washer lever ............................... 76
Windshield wipers ................................. 76, 173
Replacing ........................................... 173
Winter operation
Battery ............................................... 213
Coolant .............................................. 158
Engine oil ........................................... 159
Jumper cables ............................ 217, 218
Locks ................................................ 176
Seals ................................................. 179
Snow chains ....................................... 192
Tires .......................................... 191, 238
Washer fluid ....................................... 170
Wiper blades ...................................... 173
Wiper
Blades ............................................... 173
Lever ................................................... 76
Wiper blades
Care .................................................. 177
Changing............................................ 173
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