2015 AUDI TT ROADSTER wheel size

112 Airbag system
Front airbags
Description of front airbags
The airbag system can provide supplemental
protection to properly restrained front seat occupants.
Fig . 110 Locat ion of driver airbag: in steering wheel
Fig. 111 Locatio n of front passenger 's ai rbag: in t he in·
strument panel
Your vehicle is equipped with an "Advanced
Airbag System" in compliance with United
States Federal Motor Vehicle Safety Standard
(FMVSS) 208 as applicable at the time your
vehicle was manufactured . The safety belts
for the front seats have "pretensioners" that
help to take slack out of the belt system. The
pretensioners are also activated by the elec·
tronic control unit for the airbag system.
The front safety belts also have load limiters
to help reduce the forces applied to the body in a crash.
The airbag for the driver is in the steer ing
wheel hub ¢
fig. 110 and the airbag for the
front passenger is in the instrument panel
¢
fig . 111. The general location of the airbags
is marked "AIRBAG".
There is a lot you need to know about the air­
bags in your vehicle. We urge you to read the detailed information abo
ut airbags, safety
belts and child safety in this and the other
chapters that make up the owner's literature .
P lease be sure to heed the WARNINGS -they
are extremely important for your safety and
the safety of your passengers, especially in­
fants and small children .
A WARNING
Never rely on airbags alone for protection .
- Even when they deploy, airbags provide only supplemental protect ion.
- Airbag work most effective ly when used
with properly worn safety belts.
- Therefore, always wear your safety belts
and make sure that eve rybody in your ve­
h icle is p roperly restrained.
A WARNING
A person on the front passenger seat, es­
pec ially infants and sma ll children, w ill re­
ceive serious injuries and can even be kil­
l ed by be ing too close to the airbag when
i t inflates .
- Al tho ugh the Advanced Airbag System in
your veh icle is designed to tur n
off the
front passenger airbag if an infant or a
small child is on the front passenger
seat, nobody can absolutely guarantee
that deployment under these special
conditions is impossible in all conceiva­
b le situations that may happen during
the useful life of your vehicle .
- The Advanced Airbag System can dep loy
in accordance with the "low risk" option
under the U.S . Federal Standa rd if a child
that is heav ie r th an the typical one-year
old ch ild is on the front passenger seat
and the other condi tions for a irbag de­
p loyment are met .
- F or its own safe ty, a child sho uld always
ride properly restrained for its age and
size .
Advanced front airbag system
-
Your vehicle is equipped with a front Advanced
Airbag System in compliance with United ..,_

130 Child Safety
8_ WARNING
If, in exceptional circumstances, you must
install a forward-facing child restraint on
the front passenger's seat:
- Always make sure the forward-facing
seat has been designed and certified by
its manufacturer for use on a front seat
with a passenger front and side airbag.
-Always follow the manufacturer's in­
structions provided with the child safety
seat or carrier.
-Always move the passenger seat into its
rearmost position in the seat's fore and
aft adjustment range, as far away from
the airbag as possible before installing
the child restraint. The backrest must be adjusted to an upright position.
- Always make sure that the
PASSENGER
AIR BAG OFF
light comes on and stays
on all the time whenever the ignition is
switched on.
(D Tips
Always replace child restraints that were
installed in a vehicle during a crash. Dam­
age to a child restraint that is not visible
could cause it to fail in another collision
situation.
Advanced front airbag system and children
Your vehicle is equipped with an "Advanced
Airbag System" in compliance with United
States Federal Motor Vehicle Safety Standard
(FMVSS) 208 as applicable at the time your
vehicle was manufactured.
The Advanced Airbag system in your vehicle
has been certified to meet the "low-risk " re­
quirements for 3- and 6-year old children on
the passenger side and small adults on the
driver side. The low risk deployment criteria
are intended to reduce the risk of injury
through interaction with the airbag that can
occur, for example, by being too close to the
steering wheel and instrument panel when
the airbag inflates. In addition , the system has been certified to comply with the "sup­
pression" requirements of the Safety Stand­
ard, to turn off the front airbag for infants up
to 12 months who are restrained on the front
passenger seat in child restraints that are list­
ed in the Standard.
Even though your vehicle is equipped with an
Advanced Airbag system, a child should al­
ways ride in the seat properly restrained for
its age and size. The airbag on the passenger
side makes the front seat a potentially dan­
gerous place for a child to ride. The front seat
is not the safest place for a child in a forward­
facing child safety seat. It can be a very dan­
gerous place for an infant or a larger child in a
rearward-facing seat.
Advanced Airbags and the weight­
sensing mat in the front seat
The Advanced Airbag System in your vehicle
detects the presence of an infant or child in a
child restraint on the front passenger seat us­
ing the weight-sensing mat in the seat cush­
ion and the sensor below the safety belt latch
on the front passenger seat that measures the
tension on the safety belt.
The weight-sensing mat measures total
weight of the child and the child safety seat
and a child blanket on the front passenger
seat. The weight on the front passenger seat
is related to the design of the child restraint
and its "footprint", the size and shape of the
bottom of the child restraint as it sits on the
seat. The weight of a child restraint and its
"footprint" vary for different kinds of child re­
straints and for the different models of the
same kind of child restraint offered by child
restraint manufacturers.
The weight ranges for the individual types,
makes and models of child restraints that the
NHTSA has specified in the Safety Standard
together with the weight ranges of typical in­
fants and typical 1 year-old child have been
stored in the control unit of the Advanced Air­
bag System. When a child restraint is being
used on the front passenger seat with a .,..

146 Intellig ent technolog y
-If the power steering system should fail,
or if the eng ine is not running (for exam­
ple, while being towed), yo u wi ll st ill be
able to steer the veh icle. However, more
effort will be requ ired to do so .
- If the power steering system is not func­
tioning properly, contact your authorized
Audi dealer immediately .
Driving with your
quattro
App lies to vehicles: with all-wheel drive
With all-wheel drive, all four wheels are driv­
en.
General information
W ith all-whee l drive , power is distributed to
a ll four wheels . This happens automa tica lly
depending on your dr iv ing sty le and the road
conditions at the time. See also ~
page 141.
The all-wheel drive concept is designed for
high engine powe r. You r vehicle is exception­
ally powerful and has ex ce ll ent dr iving charac ­
teristics bot h under normal driving conditions
and on snow and ice. Always read and fo llow
safety precautions ¢
.&..
Winter ti re s
When dr iving in the w inte r, your ve hicle w ith
a ll-wheel d rive has an advantage, even with
regular tires . In winter road conditions it may
be advisable to mount winter tires (or all-sea­
son tir es) for improv ed driveability and brak­
ing: these tires must be mounted on
a ll fo ur
wheels . See also ¢ page 195, Win ter tires.
Snow cha in s
Where tire chains are mandatory on certain roads, this normally a lso applies to vehicles
with a ll-wheel drive¢
page 196, Snow
chains.
Replacing whe els /t ires
Vehicles wit h all-wheel drive mus t always
have tires of the same size . Also avoid tires
with different tread depths. For details see page
q page 191, New tires and replacing
tires and wheels .
Off-Road driving ?
Your Aud i does no t have enough g round clear­
ance to be used as an off-road vehicle. It is
therefore bes t to avoid rough tracks and un­
even terrain as much as possib le . Also refer to
¢ page 150 .
A WARNING
-Always ad just your dr iv ing to road and traf-
f ic conditions. Do not let the extra safety
afforded by all-wheel drive tempt you into
taking extra risks.
- Although the all-wheel drive is very ef­
fective, always remember that braking capacity is lim ited by tire t raction . You
should therefore not d rive at excessive
speeds on icy or slippe ry road surfaces.
- On wet road surfaces, be careful not to
d rive too fast because the front whee ls
could begin to slide o n top of the water
(aquaplan ing). If th is should occur, yo u
will have no warning from a s udden in ­
crease in eng ine speed as wit h a front ­
wheel drive vehicle. Always drive at
speeds which are su ited to the road con­
d itions. -risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimizes the
availability of electrical energy for starting the engine.
If a vehicle with a conventional energy system
is not driven for a long per iod of t ime, the bat­
te ry is discharged by idling cur rent consume rs
(e .g. immobili zer) . In cert ain circumstances it
can resu lt in the re being insufficient energy
available to start the eng ine.
Intelligent energy management in you r vehi­
cle h andles the dis trib ution of e lectr ica l ene r­
gy. Start ing ability is ma rkedly improved and
the life of the battery is extended . .,._

-Never mount used tires on yo ur vehicle if
yo u are not sure of their "previous histo­
ry." Old used tires may have been dam­
aged even though the damage cannot be
seen that can lead to sudden tire failure
and loss of vehicle control.
- If you notice unusual vibration or if the
vehicle pulls to one side when d riving, al­
ways stop as soon as it is safe to do so
and check the wheels and tires for dam­
age .
(D Note
-Please note that summer and winter
tires are designed for the cond itions that
are typ ic al in those seasons. Aud i recom­
mends using w inter t ires du ring the win-
Glossary of tire and loading terminology
Accessory weight
means the comb ined weight (in excess of
those standard items which may be replaced)
of automatic tra nsmission, power steering,
power brakes, power windows, power seats,
radio, and heater, to the extent that these
items are availab le as factory-installed equip­
ment (whether installed or not) .
Aspect ratio
means the ratio of the height to the width of
the tire in percent . Numbers of 55 or lower in­
d icate a low sidewall for improved steering re­
sponse and better overall handling on dry
pavement .
Bead
means the pa rt of the ti re that is made of
steel wires, wrapped or reinforced by ply cords
and that is shaped to fit the rim.
Bead s eparation
means a b reakdown of the bond between
components in the bead.
Cord
means the strands forming the plies in the
tire.
Tire s an d wheel s 181
ter months . Low temperatu res signifi­
cantly decrease the elastic ity of summer
t ires, which affects traction and braking
ability. If summer tires are used in very
co ld temperatures, cracks can form on
the tread bars, res ulting in permanent
ti re damage that can cause loud drivi ng
noise and unbalanced tires. Aud i is not
responsib le for this type of damage.
- Burn ished, polished or chromed rims
must not be used in winter weather. Th e
surfa ce of the rims does not have suffi­
c ien t cor rosion pro te cti on for this and
c o ul d be pe rmanen tly damaged by road
salt or similar substances. This damage
is not covered by warranty.
Cold tir e inflation pressure
me ans the t ire press ure re commended by the
vehicle manufacturer fo r a tire o f a des igna ted
size that has not bee n driven for more than a
coup le of miles (k ilomete rs) at low speeds in
the three hour pe riod before the tire press ure
is measured or adjusted.
Curb weight
means the weight o f a motor vehicle with
standard equipment including the maximum
capacity of fuel, o il, and coolant, air cond i­
tion ing and additional weight of optiona l
equipment.
E xtra load tire
means a tire designed to operate at higher
l oads and at higher inflation press ures than
the corresponding standard tire. Extra load
tires my be ident ified as "XL", "xl", "EXTRA
LOAD", or "RF" on the sidewall.
Gross Axle Weight Rating ("GAWR")
means the load-carrying capacity of a single
axle system, measured at the tire-ground in-
ter~ces.
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182 Tires and wheels
Gross Vehicle Weight Rating ("GVWR")
means the maximum total loaded weight o f
the vehicle.
Groove
means the space between two adjacent tread
ribs.
Load rating (code)
means the maximum load that a tire is rated
to carry for a given inflat ion pressure. You
may not find this informat ion on all tires be­
cause it is not requ ired by law .
Maximum load rating
means the load rating for a t ire at the maxi­
mum permissible inflation pressure for that
tire .
Maximum loaded vehicle weight
means the sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity we ight, and
(d) Production opt ions weight
Maximum (permissible) inflation pressure
means the maximum cold inflation pressure
to which a tire may be inflated . Also called
"maximum inflation press ure."
Normal occupant weight
means 150 lbs. (68 kilog rams) times the
number of occupants seated in the vehicle up
to the tota l seating capacity of your vehicle.
Occupant distribution
means distribution of occupants in a veh icle.
Outer diameter
means the overall diameter of an inflated new
tire.
Overall width
means the linear distance between the exteri ­
ors of the sidewalls of an inflated tire, includ­
ing elevations due to labeling, decorations, or
protective bands or ribs .
Ply
means a layer of rubbe r-coated parallel cords.
Production options weight
means the combined weight of those installed
regular production opt ions we ighing over 5
lbs. (2.3 kg) in excess of those standa rd items
wh ich they replace, not previously considered
in curb weight or accessory weight, including
heavy duty brakes, ride levelers, heavy duty
battery, and specia l trim .
Radial ply tire
means a pneumat ic tire in which the ply cords
that extend to the beads are laid at substa n­
tially 90 deg rees to the centerline of the
tread.
Recommended inflation pressure
see <=;> page 181, Cold tire inflation pressure .
Reinforced tire
means a tire designed to operate at higher
loads and at higher inflation pressures than
the corresponding standard tire. Re inforced
t ir es my be identified as "XL", "xl", "EXTRA
LOAD", or "RF" on the sidewall.
Rim
means a metal support for a tire or a t ire and
tube assembly upon which the tire beads are
seated .
Rim diameter
means nominal diameter of the bead seat. If
you change your wheel s ize, you will have to
purchase new tires to match the new r im di­
ameter .
Rim size designation
means rim diameter and width.
Rim width
means nom inal distance between rim flanges.
Sidewall
means that portion of a t ire between the
tread and bead .

184 Tires and wheels
Occupant loading for vehicle normal load (no luggage)
Designated seating capacity, number of occu- Vehicle normal load (no luggage), number of
pants occupants
2 2
Cold tire inflation pressure
Tire pressure affects the overall handling, performance and safety of a vehicle.
Fig. 136 Tire pressure label: located on driver's side B­
pillar
Tire pressure genera lly refers to the amount
of air in a tire that it needs it to do its job and
safely carry the combined load of the entire
vehicle and its contents. Tire pressure is
measured in kilopascals (kPa), the interna­
tional measuring unit and in pounds per
square inch (PSI). Tire pressure is based in
part on the vehicle's design and load limit -
the greatest amount of we ight that the vehi­
cle can carry safe ly and the tire size. The prop­
e r tire pressure is freq uent ly referred to as the
"recommended cold tire inflation pressure."
A ir in the tires expands when the tire heats up
because of interna l frict ion when it flexes in
use. The t ire pressure is higher when the tire
has warmed up than when it is "cold." It is the
inflation pressure in a "cold" tire that counts.
Therefore, you shou ld never let air out of a
warm tire to match "cold tire inflation pres­
sure " recommendations. The tires would then
be underi nflated and could fail suddenly .
Maintaining proper tire pressure is one of the
most important things you can do to help
avoid sudden tire failure. Underinflated tires
are a major cause of sudden tire failure . K eep­
ing tires at the rig ht pressure is also impor­
tant for sa fe and responsive vehicle handling,
traction, braking and load carrying.
Tire pres-
-ID
-
-----------------~ ,.
•===~=~~=~~=-= :g
c
==. ~: I = I ::,,. I)@ TI- ........ ....,..,____, ..... _.,....,.._,...... .... _ ... "-.................. ~ ... --................ ..
1N SIZE COlD lWIE MlS5UM. ,..-u .,...,,..... PlillSSION OU flH£US A fllOD ,_,.
AVNff -KPA, a PSI
---KPA, a PSI
-.. _ -KPA, a PSI
Fig. 137 Tire pre ssure label
SEE OW9'Ell"'S MA.HUAlFOI' ADDITIOII IAL lo~FOAMATlON VOIIIU MAMJ(L OU PROf'Wl£TAJRE '°'-'AP\USDf R£NSEIOHEMUITS
sures are particularly important when the
vehicle is being driven at higher speeds, and
then especially when heavily loaded even
within the permissible load-carrying capaci­
ties approved for your vehicle.
The recommended tire pressures for your Audi
depe nd on the kind of tires on your vehicle
and the number of passengers and/or amount
of luggage you will be transporting.
Th e tire pressure label is located on the driv­
er's side B-pillar . The tire pressure labe l lists
the recommended cold tire inflation pressures
for the vehicle at its maximum capac ity
weight and tires that were on your veh icle at
the time it was manufactured .
If you wish to improve comfort when operat­
ing the vehicle at normal load (no luggage)
up to 2 occupants, you can adjust tire pres­
sures to those specified for normal vehicle
load. Before operating the vehicle at maxi­
mum load, you must increase the tire pres­
sures to those specified for maximum vehicle
load ~&. -
Bear in mind that the tire pressure monitoring
system can only monitor the tire pressures ..,.

Tires an d wheel s 185
you have stored. The system does not
recognize the load condition of your vehicle.
The effectiveness of the ti re pressu re monitor­
ing sys tem w ill be impaired if you store no r­
mal load pressures but then operate the vehi ­
cle at its maximum load¢,&.
See the illustration¢
fig. 136 for the location
of the label on dr iver's side B-pillar (color of
the actual labe l and exact location on the ve­
hicle wi ll vary slig htly) .
Note that the fo llowing tab le is accurate at
the t ime o f go ing to press and is subject to change. In the
event of discrepancies, the ti re
pressure label (on driver's side B-pi llar) always
takes precedence .
T he table below lists the recommended cold
ti re inflation pressures for the Audi mode l
covered by your Owner's Literature at the vehi­
cle's capacity weight and the t ire sizes instal­
led on the respective models as orig inal
equipment, or as a factory option.
Model/ Tire designation Tire pressure front Tire pre ssure rear
Engine full load full load
normal load condition normal load
condition
condition
(2 occupants condition
(2 occu-
( upto 2 oc-
plus lug- (
up to 2 oc-
pants plus
cupants) gage ) cupants)
luggage)
PSI kPA PSI kPA PSI kPA PSI kPA
TT /TI S: 225 /50 Rl 7 94H All Sea -
32 220 32 220 29 200 29 200 2.0 liter son
4-cyl in-
225/50 Rl 7 94W XL Hi gh
d er
Perf or man ce
32 220 32 220 29 200 29 200
24 5/ 45 Rl 7 95 H All S ea-
32 220 32 220 29 200 29 200 son
245 /45 R1 7 95YX L High
32 220 32 220 29 200 29 200 Performance
245 /40 R18 93H All S ea-
32 220 32 220 29 200 29 200 son
2 45 /40 R18 93Y XL High
32 220 33 230 29 200 30 210 Perf or mance
255 /35 R19 96 Y XL High
32 220 32 220 29 200 29 200
Perfo rmance
X L= r einf orced or extra lo ad tire. It ma y al so app ear a s xl, EX TR A LO AD, or RF on the tir e side-
wa ll.
The correct tire pressure for the spare wheel is
located on a label on the driver's side B-pillar.
Because technical changes may be made to
vehicle equ ipment during the model year, al­
ways compare the tire size designation on the
tire pressure label on your vehicle w ith the
tires on your vehicle. Ma ke sure that the tire
size information on the veh icle label is the same
as the size of the tires on the veh icle.
Th is is espec ially important if the veh icle be­
longs to someone else o r you boug ht the vehi­
cle w ith diffe rent rims/tires or you bought the
vehicle as a prev iously owned vehicle.
Remember, your safety and that of your pas-
sengers also depends on making sure that
IJll,
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190 Tires and wheels
Tire service life
The service life of tires depends on a lot of
different things including proper installation
and balancing, correct tire pressure and driv­
ing style.
Fig. 138 Tire tread: tre ad wea r ind icators (TWI)
f ~----~
~ ..__ ____ __,
Fig. 139 Rotating t ires for more ev en wea r
Tread Wear Indicator (TWI)
The origina l tires on your veh icle have
1/16 inch (1.6 mm) high "wear indicators"
c::> fig . 138 running across the tread. Depend­
i ng on the make, there will be six to eight of
them evenly placed around the tire. Marks on
the tire sidewa ll (for example "TWI" or other
symbols) indicate the positions of the tread
wear ind icators . Worn tires must be replaced .
Different figures may apply in other countries
c::> & .
Tire pressure
Incorrect tire pressure causes premature wear
and can cause sudden t ire blow-out. For th is
reason, tire pressure must be checked at least
once a month
c::> page 186.
Driving style
Driving fast around curves, heavy acceleration
and hard braking increase tire wear.
Rotating tires for more even wear
For all four tires on your vehicle to have the
same service life, we recommend that the
front and rear tires are rotated according to
the tire manufacturer's suggested tire rota­
tion intervals. Please remember the follow­
ing :
- Tire rotation intervals may differ from the
vehicle service interva ls outlined in your
Warranty
& Maintenance Booklet.
- The longer one tire is used in one location
on the vehicle, the more it wears at certain
points; therefore, we recommend that you
follow the tire manufacturer's suggested
tire rotation intervals .
- Vehicles with front-wheel drive experience
more tread wear on the front wheels com­
pa red to all-wheel drive (quattro) .
- Please rotate tires as shown
c::> fig. 139.
-Extra care must be taken when rotating di-
rection-specific tires
c::> page 211 .
Wheel balancing
The wheels on new vehicles are balanced.
However, various situations during everyday
driving can cause them to become unbal­
anced, re sulting in vibrat ions you can usually
feel through the steer ing wheel.
Unbalanced wheels must be rebalanced to
avoid excessive wear on steering, suspension
and tires. A wheel must also be rebalanced
when a new tire is installed.
Incorrect wheel alignment
Incorrect wheel alignment can cause exces ­
sive tire wear, impairing the safety of the veh i­
cle. If tires show excessive wear, have the
whee l alignment checked by an authori zed
Audi dealer or qualified workshop.
all-wheel drive
Vehicles with quattro must always have tires
of the same size, construction and tread type .
For details see
c::> page 146 . ..,.