226 Intellig ent technol ogy
The vehicle is then stabilized by the forces act
ing on the whee l during braking. If the vehicle
is
oversteering (rear tends to sk id out of the
turn), the brakes are ma inly applied on the
wheel that is on the outside of the curve. In
the case of a vehicle that is
understeering
(tendency to slide out of the curve), the
brakes are applied as needed on the whee l
that is on the ins ide of the curve or addit ional
l y on the o ther wheels. An acoustic s ignal indi
cates when ESC b rake app lication cuts in
¢ A .
The system operates across the entire speed
range in combination with the ABS system
¢ page 229. If the Anti-Lock Brake System
(ABS) malfunctions, the ESC wi ll be out of ac
tion as well .
Activating
When you turn on the engine, ESC w ill auto
mat ica lly be act ivated and will perform a se lf
test. As soon as the test is comp leted, the sys
tem is in normal operating mode.
Offroad mod e
ESC should normally be ope rated in normal
mode because this ensures maximum vehicle
stability. If necessary, you can act ivate the
ESC offroad mode by pressing the but to n
¢ fig . 232 to obtain maximum traction and
braking ability when driving
off paved roads at
l ow speeds. In ESC offroad mode, the indica
tor light
Ii) ill uminates and the message Sta
b ilization control (E S C): Offr oad . Wa rning !
R estric te d stabilit y
appears br iefly in the dis
p lay .
The ESC offroad mode can be useful in the fo l
low ing except ional situations when slip or a
h ighly effective differential locking function is
des irable . Examp les:
- when driving with tire chains,
- when driving in deep snow or on loose
ground,
- when driving on uneven surfaces with the
whee ls severe ly unloaded (articulation), and
- when rocking the vehicle loose after it has
become stuck . When the
unusual situation is past, you
sho uld shift back to the norma l ESC operating
mode by pushing the button again . The mes
sage
S ta b ilizat ion cont rol (ES C): O n then ap
pears briefly in the display.
H ill desc ent control
The hill descent control is switched on in ESC
offroad mode . When slowly descending steep
gradients on loose ground or when the axles
are articulated, hill descent control provides ass istance by automatically apply ing the
brakes to keep vehicle speed constant. The ve
hicle is also rendered easier to steer by selec
t ive d istr ibut ion of braking force. Hill descent
control intervenes when:
- the acce lerator pedal is not pressed,
- the vehicle is travelling less than 12 mph
(20 km/h),
- a steep gradient is detected,
- wheel behavior indicates loose ground or
conditions with poor adhesion (e .g. also axle
art iculation).
Hill descent contro l operates both d riving for
ward and in reverse. Active hill descent con
tro l is deactivated by pressing the accelerator
pedal until the condit ions for activation al
ready listed are met again .
A WARNING
--
- The Electronic Stabilization Contro l is
neverthe less s ubject to the laws of phys
ics. It is part icularly important to pay at
tention to this fact on wet and slippe ry
roads . It i s therefore important that you
always adapt your dr iving to the cond i
tion of the road and traffic conditions . Do
not a llow the increased safety provided
by the E lectronic Stabilization Contro l
system to lull you into accepting addi
tional safety risks .
- Please be aware that in ESC offroad
mode, particularly on a smooth and s lip
pe ry road, the wheels may have an in
creased tendency to sp in and the vehicle
may b reak away - dange r of skidding!
~
@ Tips
- When the engine is running, never hold
the steer ing whee l turned a ll the way to
the right or t o the left f or longer than 15
seconds. The power steering pump w ill
overheat the hydraulic f lu id if you keep
hol ding the steer ing wheel turned all the
way. This is likely to damage the power
steering system.
- If the power steer ing system should fail
ent irely, or if the engine is not running
(fo r example, while being towed), you
will still be ab le to steer the vehicle.
However,
considerably more effort will
be required to do so.
- If the power s teer ing system should
have a leak, or is not functioning proper
l y, contact yo ur authorized Audi dealer
immediately.
- The power stee ring system requires a
spec ially formulated hydraulic fluid. The
power steering reservo ir is the one locat
ed farthest to the rear on the left side of
the engine compartment
c> page 266.
The co rrect flu id level in the reservoir is
i mportant for proper functioning of the
power steer ing .
Driving with your
quattro ®
With all-wheel drive, oil four wheels ore driv
en.
Gener al information
W ith all -whee l dr ive , power is distributed to
a ll fo ur wheels. This happens automatica lly
depending on yo ur driving sty le and the road
conditions at the time . See also
¢ page 227,
Electronic differential lock (EDL) .
Winter tires
When driving in the w inter, your ve hicl e w it h
all -wheel drive has an advan tage, even with
regu lar tires . In winter road conditions it may
be advisable to mount winter tires (or all -sea
son t ires) for improved driveability and brak-
Int ellig ent technolog y 231
ing: these tires must be mounted on all four
wheel s. See also ¢
page 295, Winter tires .
Tire chains
Where tire chains are mandatory o n certain
roads, this no rma lly also app lies to veh icles
with all-wheel drive¢
page 296, Snow
chains.
Replacing wheels /tires
Vehicles with all-wheel drive must always have ti res of t he same s ize. A lso avo id tires
with different t read depths. For det ails see
page
c!;> page 291, New tires and replacing
tires and wheels .
_& WARNING
A lways adj ust yo ur driv 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.
-Altho ugh the all-wheel drive is very ef
fective, always remember that braking
capacity is lim ited by tire traction. You
should therefore not drive at excessive
speeds on icy or slippe ry road surfaces .
- On wet road surfaces, be careful not to drive too fast because the front wheels
could begin to slide o n top of the water
(aquaplaning). If th is should occur, yo u
will have no warning from a s udden in
crease in engine speed as w ith a front
wheel drive vehicle. Always drive at
speeds which are suited to the road con
ditions -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 conventiona l 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. immobi liz e r). In certa in circumstan ces it ..,_
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A WARNING
Sudden tire failure can lead to loss of con
trol, a crash and serious personal injury!
- Never drive a vehicle when the tread on
any tire is worn down to the wear indica
tors.
- Worn tires are a safety hazard, they do
not grip well on wet roads and increase
your risk of "hydroplaning" and loss of
control.
- Always keep chemicals that can cause
tire damage, such as grease, oil, gasoline
and brake fluid away from t ires.
- Tires age even if they are not be ing used
and can fail suddenly, especially at high
speeds . Tir es that are more than 6 years
old can only be used in an emergency
and then with special care and at lower
speeds.
- Never mount used tires on your vehicle if
you 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. Tires and wheels 291
New tires and replacing tires and wheels
New tires and wheels have to be broken in
.
Fig. 255 Tir e specificat ion codes on t he s idewall o f a
tire
No. Description
CD Passenger car tire (where applicable)
@ Nominal width of tire in millimeters
® Ratio of height to width (aspect ratio)
© Radial
® Rim diameter code
® Load index and speed rat ing
(f) U.S. DOT tire identification number
® Audi Original tire
® Sever snow conditions
@ Tire ply composition and materials
used
@ Maximum load rating
@ Treadwear, traction and temperature
grades
@ Maximum permissible inflation pres-
sure
The tires and rims are essential parts of the
vehicle's design . The ti res and rims approved
by Audi are spec ially matched to the charac
teristics of the vehicle and can make a major .,.
•
29 4 T ire s and wheel s
-All four wheels must be fitted with radia l
t ires of the same type, size (roll ing c ir
cumference) and the same tread pattern.
Driv ing with different tires reduces veh i
cle handling and can lead to a loss of
control.
- If the spare tire is not the same as the
t ir es that are mounted on the veh icle -
for example with wi nter tires - on ly use
the spare tire for a short period of time
and dr ive with extra care. Refit the no r
ma l road whee l as soon as safely possi
ble.
- Never drive faster than the maxim um
speed for which the tires on your vehicle
are rated because tires that are drive n
faster than their rated speed can fail
sudden ly.
- Overloading ti res cause heat build- up,
sudden tire failure, including a blowout
and sudden deflation and loss of control.
- Temperature grades app ly to tires that
are properly inflated and not over or un
derinflated.
- For technical reasons it is not a lways
poss ible to use wheels from other
vehicles -in some cases not even wheels
from the same vehicle model.
- If you install wheel tr im discs on the ve
hicle whee ls, make sure that the air flow
to the brakes is not blocked . Reduced air
flow to the brakes can them to overheat,
increasing stopping d istances and caus
ing a collision.
- Run flat t ires may on ly be used on
vehicles that we re eq uipped w it h them
at the f acto ry. The vehicle must have a
chassis des igned for r un flat t ires . Incor
rect use of run flat tires can lead to vehi
cle damage or acc idents . Check with an
authorized Audi dealer or t ire specia list
to see if your vehicle can be equipped
with run flat t ires. If run flat tires are
used, they must be installed o n all four
wheels. Mix ing tire types is not permit
ted. (D Note
- For technical reasons, it is not generally
poss ible to use the wheel rims from oth
er veh icles. T his can hold tr ue for wheels
of the same vehicle type.
- If the spare tire is diffe rent from the
tires that you have mounted on your ve
hicle (for example winter tires or wide
profi le tires), then use the spare tire for a
short period of time only and drive w ith
extra care. Replace the flat tire w it h the
ti re mat ching the othe rs on your vehicle
as soon as possi ble.
- Never d rive without the valve stem cap.
T he v alves co uld get damaged.
@ For the sake of the environment
Dispose of o ld tires in accordance w ith the
l ocal requirements.
Uniform tire quality grading
- Tread wear
- Tra ction AA A B (
- Temperature ABC
Quality grades can be found where applicab le
on the tire s ide wall between tread shoulder
and maximum section width
c> page 291,
fig . 255 .
For example: Tread wear 200 , Traction AA ,
Temperature A .
All passenger car ti res must conform to Feder
al Safety Requirements in add ition to these
grades .
Tread wear
The tread wear g rade is a comparative rating
based on the wear rate of the tire when tested
u nder contro lled conditions o n a specified
government test course.
F o r example, a tire graded 150 wo uld wear
one and one ha lf (11/2) times as well on the
government course as a ti re graded 100.
The relative perform a nee of ti res depends
upon the actua l conditions of their use, how
ever, and may depart sign ificantly from the
norm due to var iat ions in dr iving habits, serv
ice practices and differences in road character
istics and climate .
Trac tion
The traction grades, from highest to lowest,
are AA, A, Band
C. Those grades represent the
tire's ability to stop on wet pavement as measured under controlled cond itions on
specified government test surfaces of asphalt
and concrete . A tire marked C may have poor
traction performance ¢,&. .
Temp erature
The temperature grades are A (the h ighest),
B, and
C, representing the t ire's resistance to
the generat ion of heat and its ability to dissi
pate heat when tested under controlled condi
tions on a specified i ndoor laboratory test
wheel.
Sustained high temperature can cause the
materia l of the tire to degenerate and reduce
tire life, and excessive temperature can lead
to sudden ti re fa ilu re ¢ ,&. .
The grade
C corresponds to a level of perform
ance which all passenger car tires must meet
u nder the Federa l Moto r Veh icle Safety Stand
a rd No.
1 09. G rades Band A represent h igher
l eve ls of perfo rmance on the laboratory tes t
wheel than the m inimum required by law .
A WARNING
The traction grade assigned to this ti re is
based on stra ight-ahead b raking t raction
tests, and does not include acceleration,
cornering, hydrop lan ing or peak traction
character istics.
A WARNING
The temperature grade for this t ire is es
tablished for a t ire that is p roperly inflated
and not overloaded. Excessive speed, un
derinflation, or excessive loading, either
-
Tire s an d wheel s 295
separately or in combinat ion, can ca use
heat bui ldup and possible tire failure.
Winter tires
Winter tires can improve vehicle handling on
snow and ice. At temperatures below 45 °F (7 °C) we recommend changing to winter
tires.
In some heavy snow areas, local governments
may require true winter o r "snow" tires, those
with very deeply cut tread. These tires should
o nly be used in pairs and be installed o n all
four wheels . Make sure you purchase snow
t ires that are the same size and construction
type as the other tires on you r vehicle.
Your vehicle is equipped with all-wheel drive,
th is w ill improve traction during winter driv
i ng, even with the standa rd tires . However, we
strong ly recommend that you always equip all
fo ur wheels on you r vehicle wit h corre ct ly fit
ted winter tires or all-season t ires, when win
te r road cond itions are expected . This also im
proves the veh icle's braking per formance and
reduces stopping dista nces.
Summe r tires provide less grip on i ce and
snow.
Winter tires (snow tires) must always be fitted
o n all fo ur wheels .
Ask your authorized Audi dealer or qualified
workshop for permitted
winter tire size s. Use
o nly rad ial w inter t ires.
Winter tires lose their effectiveness when the
tread is worn down to a depth of
0 .157 inch
(4 mm) .
Only drive w ith w inter t ires under w inter con
dit ions. Summer t ires handle better when
there is no snow or ice on the roads and the
temperature is above 45 °F (7 °() .
If you have a flat tire, see notes on spare
whee l
¢page 291.
Please a lways remember that winter tires may
have a lowe r speed rating than the tires o rigi -
nally installed on your vehicle at the time it .,.
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