2014 AUDI A8 traction control

Intelligent technology Notice about data
recorded by vehicle
control modules
Your vehicle is not equipped with an Event Da­
ta Recorder (EDR), installed by some manu­
facturers for the express purpose of capturing
data for retrieval after an accident or crash
event. EDR's are sometimes called "crash re­
corders".
Some state laws restrict the retr ieval or down­
loading of data stored by EDR's that were in­
stalled in a vehicle for the express purpose of
retrieving data after an accident or crash
event without the owner's consent.
Although your vehicle is not equipped with an
EDR, it is equipped with a number of electron­
ic control modules for various vehicle systems
such as, for examp le, engine function, emis­
sion control, as well as for the airbags and
safety belts.
These electronic control modules also record
vehicle-related data during norma l vehicle op­
eration for diagnostic and repair purposes.
The recording capacity of the electronic con­
trol modules is limited to data (no sound is re­
corded) and only a small amount of data is ac­
tually recorded over a very limited period of
time and stored when a system fault or other
condition is sensed by a control unit. Some of
the data then stored may relate to vehicle
speed, direction, braking as we ll as restraint
system use and performance in the event of a
crash or other condition. Stored data can only be read and downloaded with special equip­
ment.
Electronic Stabilization
Control (ESC)
Description
ESC helps to improve road holding and vehicle
dynamics to help reduce the probability of
skidding and loss of veh icle control. It works
only when the engine is running. ESC detects
Intelligent technology 199
certain difficult driving situations, including
when the vehicle is beginning to spin (yaw)
out of control and helps you to get the veh icle
back under control by se lectively braking the
wheels, and/or reducing engine power and
providing steering ass istance to help hold the
vehicle on the driver's intended course. The in­
dicator light
JjJ in the instrument cluster
blinks when ESC is taking action to help you
control the vehicle.
ESC has limitations .
It is important to remem­
ber that ESC cannot overcome the laws of
physics.
It will not always be able to help out
under all conditions you may come up against.
For example, ESC may not always be able to
help you master situations where there is a
sudden change in the coefficient of friction of
the road surface. When there is a section of dry road that is suddenly covered with water,
slush or snow, ESC cannot perform the same
way it would on the dry surface. If the vehicle
hydroplanes (rides on a cushion of water in­
stead of the road surface), ESC will not be
able to help you steer the vehicle because con­
tact with the pavement has been interrupted
and the vehicle cannot be braked or steered .
During fast cornering, particularly on winding
roads, ESC cannot always deal as effectively
with difficult driving situations than at lower
speeds. When towing a trailer, ESC is not able
to help you regain control as it would if you
were not tow ing a trailer.
A lways adjust your speed and driving style to
road, traffic and weather conditions. ESC can­
not override the vehicle's physical limits, in­
crease the available traction, or keep a vehicle
on the road if road departure is a result of
driver inattention. Instead, ESC improves the
poss ibility of keeping the vehicle under con­
trol and on the road dur ing extreme maneu­
vers by using the driver's steering inputs to
help keep the vehicle going in the intended di­
rection. If you are traveling at a speed that
causes you to run off the road before ESC can
provide any assistance, you may not experi­
ence the benefits of ESC.
•
•

200 Intellig ent technol ogy
ESC includes and/or works together with the
anti-lock braking system (ABS), brake assist
system, anti-slip regulat ion (ASR), electronic
d ifferential lock (EDL), dynamic steering* and
electronic interaxle differential lock*. ESC is
switched on all the time. In certain situations
when you need less tract ion, you ca n sw itch
off ASR by pressing the button above
~ page 201, fig. 188 the se lector lever. Be
sure to sw itch ASR on aga in when you no lon­
ger need less traction.
Anti -lock braking system (ABS )
ABS prevents the wheels from locking up
when braking. The vehicle can still be steered
even du ring ha rd b raking . Apply steady pres­
sure to the brake pedal. Do not pump the ped­
a l. A pulsing in the brake peda l indicates that
the system is he lping you to brake the vehicle.
Br ake assist system
The brake assist system can decrease brak ing
d istance. It increases braking power when the
d river p resses the brake pedal q uick ly in emer­
gency situations. You must press and hold the brake peda l until the situation is over. In
vehicles with adaptive cruise control*, the brake assist system is more sensitive if the
d istance detected to the vehicle ahead is too
small.
Anti- slip regulati on (ASR )
ASR reduces engine power when the drive
wheels begin to spin and adapts the force to
the road condit ions. This makes it easier to
start, accelerate and drive up hills.
El ectronic diff erential lo ck (EDL )
The ED L brakes wheels that are spinning and
transfers the drive power to the other drive
wheel or whee ls if the vehicle is equipped with
all whee l drive*. This funct ion is available up
to about 7S mph (120 km/h).
In extreme cases, EDL a utomatica lly switches
off to help keep the brake on the braked whee l
from overheating. EDL will switch on again au­
tomatically when conditions have returned to normal.
Dynamic ste ering *
On vehicles with dynamic s teering, ES C helps
stabilize the steering in certain situations.
Electronic interaxle differential lock
function*
T he electronic interaxle differentia l lock f unc­
tion activates when driving thro ugh curves.
Braking is targeted toward the wheels on the
inside of the curve as needed . This he lps to
minimize front whee l skid, improves traction
and allows for more precise driving through
curves .
A WARNING
- ESC, ABS, ASR, EDL, dynamic steering*
and the electronic interaxle differential loc k function* cannot overcome the laws
of physics. This is espec ially impo rtant
on slippery o r we t roads.
If the systems
begin acting to stabilize your vehicle, you
should immediately change yo ur speed
to match the road and traffic conditions .
Do not let the increased safety provided
by these systems tempt you to take risks. Doing so will increase the risk of a loss of
veh icle control, collision and ser ious per­
sonal injur ies.
-Always adapt your speed to road, traffic and weather conditions. The risk of los­ing control of the vehicle increases when
d riving too fast, espec ially through
curves and on slippery or wet roads, and
when driving too close to vehicles up
ahead. ESC, ABS, the brake ass ist sys ­
tem, EDL, ASR, dynamic steering * and
the electron ic interaxle differential lock
function* cannot prevent collisions.
- Always accelerate with special care on
even, smooth s urfaces such as those that
are wet or covered with ice and snow.
The drive wheels can spin even w ith
these assistance systems that cannot al­
ways he lp to red uce the risk of loss of ve­
h icle control.
-

204 Intelligent technology
The correct f luid leve l in the reservoi r is
important for proper functioning of the
power steer ing.
Driving with your
quattro
With All Wheel Drive, all four wheels are driv­
en.
General information
With All Wheel Drive, power is distributed to
all four wheels . This happens automatically
depending on your dr iving style and the road
conditions at the t ime . See a lso
c::;, page 199.
W ith the sport differential*, power distribu­
tion to the rear wheels is var iable and can be
ad justed with Aud i drive select*
c::;,page 110.
Always read and fo llow safety precautions
¢ &, .
Winter tires
When driv ing in the w inter, your vehicle w ith
A ll Wheel Drive has an advantage, even with
r egular tires. In winter road conditions it may
be advisable to mount winter tires (or all-sea­
son tires) for improved driveability and brak­ ing: these tires must be mounted on all four
wheels. See also c:;, page 263, Winter tires.
Snow chains
Where snow chains are mandatory on certain
roads, this normally a lso applies to vehicles
with A ll Wheel Drive
¢ page 264, Snow
chains.
Replacing wheels/tires
Vehicles with A ll Wheel Dr ive must always
have tires of the same size . Also avoid ti res
with different tread depths. For details see
page
c:;, page 2 59, New tires and replacing
tires and wheels.
Off-Road driving?
Your Aud i does not have enough ground clear­
ance to be used as an off -road vehicle. It is
therefore best to avoid rough tracks and un ­
even terrain as much as possible. Also refer to
c::;, page209.
A WARNING
Always adjust your driving 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 traction. You
should therefore not drive at excessive
speeds on icy or slippery road surfaces.
- On wet road surfaces, be careful not to
drive too fast because the front wheels
could begin to slide on top of the water
(aquaplaning) . If this should occur, you
will have no warning from a sudden in­
crease in eng ine speed as with 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 ene rgy system
is not driven for a long period of time, the bat­
tery is discharged by idling current consumers
(e .g . immobilizer). In certain circumstances it
can resu lt in there being insufficient energy
available to start the engine .
Intelligent energy management in your vehi­
cle handles the distribution of e lectrica l ener­
gy. Starting ability is markedly improved and
the life of the battery is extended.
Basically, energy management consists of
battery diagnosis , idling current manage­
ment
and dynamic energy management.
Battery diagnosis
Battery diagnosis continuously determines
the state of the battery. Sensors determine
battery voltage, battery current and battery ..,.

Incorrect wheel alignment
Incorrect wheel alignment can cause exces­
sive tire wear, impairing the safety of the vehi­
cle. If tires show excessive wear, have the
wheel alignment checked by an authorized
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 ~page 204.
_& 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 tires.
- Tires age even if they are not being used
and can fail suddenly, especially at high
speeds . Tires 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 toss of vehicle control. Tires and wheels 259
New tires and replacing tires and wheels
New tires and wheels have to be broken in
.
Fig. 212 Tire specificat ion codes on t he s idewall o f a
tire
No. Description
@ 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 rating
0 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 tires and rims approved
by Audi are specialty matched to the charac­
teristics of the vehicle and can make a major .,.

26 2 T ire s and wheel s
Driving with different tires reduces vehi­
cle handling and can lead to a loss of
co ntrol.
- I f the spare tire is not the same as the
t ires that are mounted on the veh icle -
for example with winter tires - only use
the spare tire for a short period of time
and dr ive with extra care . Refit the nor­
ma l road wheel as soon as safely possi­
ble.
- Never drive faste r than the maximum
speed for which the tires on your veh icle
are rated because ti res that a re driven
faster than their rated speed can fail
sudden ly .
- Overloading t ires cause heat build- up,
sudden tire failure, including a blowout
and sudden deflation and loss of control.
- T emperature grades app ly to tires that
are properly inflated and not over o r un­
derinflated .
- For technical reasons it is not a lways
possible to use wheels from other
vehicles -in some cases not even wheels
from the same vehicle model.
- If you insta ll wheel trim discs on the ve­
hicle whee ls, make sure that the air f low
to the brakes is not blocked. Reduced air­
flow to the brakes can them to overheat, increasing stopping distances and caus­
ing a collision .
- Run flat t ires may on ly be used on
vehicles that were equ ipped w ith them
at the facto ry . The vehicle must have a
chassis des igned for run f lat t ires . Incor­
rect use of run flat tires can lead to vehi­
cle damage or acc idents. Check with an
au thorized Aud i dealer or ti re specia list
to see if your vehicle can be equipped
with run f lat tires. If run flat tires are
used, they must be installed on all four
wheels . Mix ing tire types is not permit­
ted .
(D Note
-For technica l reasons, it is not generally
possib le to use the whee l rims from oth- er veh
icles. This can hold true for wheels
of the same vehicle type.
- If the spare tire is d iffe rent from the
tires that yo u have mounted on your ve­
hicle (for example winter tires o r 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 ith the
tire matching the others on your vehicle as soon as possible .
- Never drive without the valve stem cap .
T he valves could get damaged .
® For the sake of the environment
Dispose of o ld tires in accordance with the
l ocal requirements.
Uniform tire quality grading
- Tread wear
- Traction AA A B C
- Temperature ABC
Quality grades can be found where applicab le
on the t ire s ide wall between tread shou lder
and maximum section width
c> page 259,
fig. 212 .
For example : Tread wear 200, Traction AA,
Temperature A.
All passenger ca r tires must conform to Feder­
al Safety Requirements in addition to these
grades.
Tread wear
T he tread wear grade is a comparative rating
based on the wear rate of the t ire when tested
u nder contro lled conditions o n a specified
government test course .
For example, a tire graded 1S0 would wear
one and o ne ha lf ( 11/2) times as well on the
gover nment course as a t ire g raded 100 .
The relative performance of tires depends upon the actual conditions of their use, how­
ever, and may depa rt s ignificantly from the
norm due to va ria tions in d riving hab its, se rv­
ice practices and differences in road character-
istics and climate.
ll-

Traction
The traction grades, from highest to lowest,
a re AA, A, Band
C. Those grades represent the
tire's ability to stop on wet pavement as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete . A tire marked C may have poor
traction performance¢ .&..
Temp eratu re
The temperature grades are A (the highest),
B, and
C, representing the tire 's resistance to
the generat ion of heat and its ability to dissi­
pate heat when tested under controlled condi­
tions on a specified indoor laboratory test
wheel.
Sustained high temperature can cause the
material of the tire to degenerate and reduce
tire life, and excessive temperature can lead
to sudden tire failu re ¢ .&. .
The grade C corresponds to a level of perform­
ance which all passenger car tires m ust meet
u nder the Federa l Motor Ve hicle Safety Stand­
ard No.
1 09. Grades Band A represent higher
l eve ls of pe rformance on the laboratory test
wheel than the m inimum required by law.
_& WARNING
Th e traction grade assigned to this tire is
based on stra ight-ahead b raking t raction
tests, and does not include acceleration,
cornering , hydrop laning or peak traction
character istics.
A WARNING
The temperature grade for this t ire is es ­
tablished for a t ire that is properly inflated
and not overloaded. Excessive speed, un­
derinflation, or excessive loading, either
separate ly or in combination, can cause
heat buildup and possibl e tire fa ilu re.
-
Tire s an d wheel s 263
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 w inter o r "snow" tir es, those
with very deeply cut t read. These tires should
o nl y be used in pairs and be installed o n all
f o ur wheels . Make sure you p urchase snow
ti res that are the same size and cons truc tion
type as the other tires on yo ur vehicle .
I f your veh icle is eq uipped w ith all-whee l
drive *, t his w ill improve trac tion durin g w in ter
driv ing, even wi th the s tanda rd tires. Howev ­
er, we strongly recommend that you always
equip all four wheels on your veh icle w ith cor­
rect ly fitted winter tires or all-season t ires,
when winter road condit ions are expected.
This also improves the veh icle 's b rak ing per­
fo rmance and reduces stoppi ng d ista nces .
Summer tires provide less grip on ice and
snow.
Winter tires (snow tires) must always be fitted
o n all fo ur whee ls .
As k your au thori zed A udi d ealer or qualified
workshop for permit ted
winter tire size s. Use
o nl y radial winter ti res .
Win ter tires lose their effec tiveness whe n the
tread is worn down to a depth o f
0.15 7 inch
(4 mm) .
Only d rive w it h w inte r tir es under w inte r con­
di tions. S umme r tir es handle bette r whe n
t h e re is no s now o r ice on the ro ad s an d the
temperature is above 45 ° F (7 °C) .
I f you have a flat t ire, see notes on spare
whee l
¢page 259.
Please a lways remember that winter tires may
have a lowe r sp eed rating than the tires o rig i­
nally i nstalled on your veh icle at t he time it
was ma nufactu red. Please see ¢
page 260,
Speed ra ting (letter code)
for a lis ting o f th e
speed ra ting lette r codes and the max imum
speed at which the tires can be driven .
111>-
•
•