2014 AUDI A8 engine

occupant will slam violently into the steering
wheel, instrument panel, windshield , or what­
ever else is in the way
c::> fig. 158. This impact
with the vehicle interior has all the energy
they had just before the crash.
Never rely on airbags alone for protection.
Even when they deploy, airbags provide only
additional protection. Airbags are not sup­
posed to deploy in all kinds of accidents. Al­
though your Audi is equipped with airbags, all
veh icle occupants, including the driver, must
wear safety belts correctly in order to mini­
mize the risk of severe injury or death in a
crash.
Remember too, that airbags will deploy only
once and that your safety belts are always
there to offer protection in those accidents in
which airbags are not supposed to deploy or
when they have already deployed. Unbelted
occupants can also be thrown out of the vehi­
cle where even more severe or fatal injuries
can occur.
It is also important for the rear passengers to
wear safety belts correctly. Unbelted passen­
gers in the rear seats endanger not only them­
selves but also the driver and other passen­
gers
c::> fig. 159. In a frontal collision they will
be thrown forward violently, where they can
hit and injure the driver and/or front seat pas ­
senger.
Safety belts protect
People think it's possible to use the hands to
brace the body in a minor collision . It's simply
not true!
Fig. 160 Driv er is cor rect ly r est rain ed in a sudden brak­
ing ma neuve r
Safety belts 147
Safety belts used properly can make a big dif­
ference. Safety belts help to keep passengers
in their seats, gradually reduce energy levels
applied to the body in an accident, and help
prevent the uncontrolled movement that can
cause serious injuries . In addition, safety belts
reduce the danger of being thrown out of the
vehicle .
Safety belts attach passengers to the car and
give them the benefit of being slowed down more gently or "softly" through the "give" in
the safety belts, crush zones and other safety
features engineered into today's vehicles. By
"absorbing" the kinetic energy over a longer
period of time, the safety belts make the
forces on the body more "tolerable" and less
likely to cause injury .
Although these examples are based on a fron­
tal collision, safety belts can also su bsta ntia l­
ly reduce the risk of injury in other kinds of
crashes. So, whether you're on a long trip or
just going to the corner store, always buckle
up and make sure others do, too. Accident sta­
tistics show that vehicle occupants properly
wearing safety belts have a lower risk of being
injured and a much better chance of surviving
an accident. Properly using safety belts also
greatly increases the ability of the supplemen­
tal airbags to do their job in a collision . For
this reason, wearing a safety belt is legally re­
quired in most countries including much of
the United States and Canada.
Although your Audi is equipped with a irbags,
you still have to wear the safety belts provid­
ed. Front airbags, for example, are activated
only in some frontal collisions. The front air­
bags are not activated in all frontal collisions,
in side and rear collisions, in roll overs or in
cases where there is not enough deceleration
through impact to the front of the vehicle.
The same goes for the other airbag systems in
your Audi. So, always wear your safety belt
and make sure everybody in your veh icle is
properly restrained!

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.
-

@ Tips
-ABS and AS R on ly wor k co rrectly when
a ll fo ur wheels are eq uipped w ith identi­
ca l tires . Different tire s izes can lead to a
r educt io n in eng ine power.
- You may hear noises when the sys tems
desc ribed are working.
Switching on and off
Intelligent technology 201
- If the ind ica tor li ght DJ o r til1 (U SA
mo dels)/ [!] (Canada models) appea rs,
there may be a malfunc tion
r:::> page 19,
¢page 18.
ESC turns on automatically when you start the engine.
Fig . 188 Center co nsole with ESC O FF bu tton
ESC levels
Sport mode on
The following si tua tions are exceptions whe re
it may be usefu l to switch o n sport mo de to
allow the w heels to spi n:
- Rockin g the vehicle to free it when i t is st uck
- Dr iv ing in deep s now o r on loose g ro un d
- Dr iving with snow chains
Sport mode off
Behavior
T he E SC and AS R sta bilization f unct io ns The fu ll sta biliz ati on f uncti on o f the ES C
are limited¢ ,&.
Operation Press the [ru button .
Indicator II turns on .
lights
Driver mes· Stabilization control (ESC): Sport
sages Warning! Reduced stability
A WARNING
Yo u should o nly sw itch sport mo de on i f
your dr iv ing abili ties and road cond itions
permit.
- The stabilization function is limited
when sport mode is sw itched on. The
dr iv ing whee ls co uld spin and the vehicle
cou ld swe rve , especially on slick or slip ­
pery road surfaces.
(D Tips
Sport mode cannot be switched o n when
adapt ive cr uise c ontrol* is sw itched on.
-
and AS R is availab le again .
Press the
[ru button again .
II tur ns off.
Stabilization control (ESC): On
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The bra ke s on today's au to m obiles a re s till
sub ject t o wear, depe nding la rgely o n ope rat ­
i ng con dit ions and d riving habits¢
A . On
vehicles that are either driven most ly in stop­
and-go city traff ic or are driven hard , the
brake pads should be checked by your author­
ized Audi dealer more often than specif ied in
t h e
Warranty & Maintenance booklet . Failure .,..

202 Intellig ent technol ogy
to have your brake pads inspected can result
in reduced brake performance.
On steep slopes, yo u shou ld use the b rak ing
effect of the engine. Th is way, you prevent un­
necessary wear on the brake system. If you
must use your brakes, do not hold the brakes
down continuously. P ump the brakes at inter ­
vals.
Operating nois e
Noises may occur when braking depending on
the speed, braking force and outside condi­
tions such as temperature and humidity.
E ff ect of water and road salt
In certain situat ions, for example after driving
through water , in heavy ra in , after overn ight
condensation or after washing your car, the braking effect can be reduced by moisture or
ice on the brake rotors and brake pads. The
brakes must be dried first with a few careful
brake applications.
At higher speeds and with the windshield wip­
ers turned on, the brake pads press against
the brake rotors for a short amount of time.
This occurs at regular intervals without the
driver noticing and provides for bet ter brake
response time under wet condit ions .
The effectiveness of the brakes can be reduced
when the vehicle is dr iven on a salt-covered
road and the brakes are not used . Likew ise,
you clean off accumulated salt coating from
brake discs and pads with a few caut ious ap­
plications of the brake
9 .&, .
Cor ro sion
There may be a tendency for dirt to build up
on the brake pads and corrosion to form on
the discs if the car is not dr iven regularly or
only for short t rips with little use of the
b rakes .
If the brakes are not used frequently , or if cor­
rosion has formed on the discs, it is advisable
to clean off the pads and discs by braking
firm ly a few times from a mode rately high
speed
9 .&, .
Faults in the brake syste m
If you shou ld notice a sudden increase in
brake pedal trave l, then one of the two brake
circuits may have fai led
9 & .
Low bra ke fluid lev el
Malfunctions can occu r in the bra ke system if
the b rake fluid level is too low. The brake flu id
level is monitored electro nica lly.
Brake lining we ar statu s
Brake lining wear may be checked by visual in­
spect ion of the condition of the brake pads
th rough the open ings in the wheel. If neces ­
sary, the wheel may be removed for t his i n­
spect ion
9 page 2 72, Changing a wheel.
A WARNING
- You shou ld perform braking maneuvers
for the purpose of cleaning the brake system only if road conditions permit.
Other road users must not be put at risk -
you may cause an accident!
- Before descending a steep grade, reduce
speed and sh ift transmission into a lower
gear or lower dr iving range. Do not ride
the brakes or hold the pedal down too
long or too often . This could cause the
b rakes to get hot and diminish braking
efficiency.
- Do not "ride the brakes" by rest ing your
foo t on the pedal when you do not intend
to brake. This may cause the brakes to
overheat, premature wear and increased
stopping distance.
- Unde r certain cl imatic and operat ing
conditions such as passing thro ugh wa ­
ter, driving in heavy rain or after washing
the vehicle, the effectiveness of the brakes can be reduced. In winter, ice can
accumu late on the brake pads, linings,
d iscs and drums. Carefully app ly brakes
for a test. Brakes will dry and ice coat­ ings will be cleaned off after a few care­
fu l brake applicat ions.
- Driving for an extended period of t ime on
salt-covered roads without using your brakes can a lso affect bra king efficiency.
~

Clean off accumulated salt coating from
brake discs and pads with a few careful
brake applicat ions .
-If you damage the front spoiler, or if you
install a different spoiler, be sure the air
flow to the front brakes is not obstruct­ ed . Otherwise the brake system could
overheat reducing the effectiveness of
the ent ire brake system.
- Failure of one brake c ircuit will impair
the braking capability resulting in an in­
cr eased stopp ing distance. Avoid driv ing
the vehicle and have it towed to the near­ est Aud i dea ler or q ualified wor kshop .
- Never let the vehicle rol l to a stop w ith
t he engine shu t off.
- If the brake booster is not work ing, the
brake pedal must be pressed conside ra­
bly harder to make up for the lac k of
booster assistance.
Brake booster
The brake booster adds extra braking power.
The brake booster works w ith vacuum pres ­
sure which is created only when the engine is
ru nning
9 ,&. .
,&. WARNING
-Never le t the vehicle ro ll to a stop w ith
t he engine shu t off.
- If the brake booster is not work ing, fo r
ex ample when towing your ve hicl e, or
because the b rake booste r has somehow
been damaged, the brake pedal must be
pressed considerab ly harder to make up
for the lack of booster assistance.
Servotronic - advanced
power steering system
-
The power steering systems use the power of
the running engine to allow precise steering
with little effort.
The advanced Servotronic power steering sys­
tem senses the road speed and electron ically
ad ju sts powe r ass istance to provide comfor ta-
Int ellig ent technolog y 203
ble and safe steering response exactly match ­
ed to th e vehicle speed .
Power steer ing will not work if the engine is
off . As a result, the steering wheel will be h ard
to tu rn.
T he powe r stee ring fluid level is checked d ur­
i ng t he sched uled maintena nce services.
(D Note
If there is an e lectronic malfunction, ser­
votronic
will s till fu nction like a conven­
tiona l powe r steering system, providing a
constant steering s upport force tha t is no
l onge r proportionate to the vehicle speed.
This is most noticeab le when t urni ng the
steering wheel at low speeds (for example
when parking), -more effort w ill be re­
quired than usual.
- Be aware of the different than usual steering response and adjust your steer­
ing force accordingly.
- Have the problem checked and set right by an Audi dealer as soon as possible.
(D Tips
-When the engine is running, never hold
the steering wheel turned all the way to
the right or to the left for longer than 15
seconds . The power steering pump will
overheat the hydraulic fluid if yo u keep
holding the stee ring wheel turned all the
way. This is likely to damage the power
steering sys tem.
- If the powe r stee ring system should fa il
entire ly, o r if t he engine is not runn ing
(for example, wh ile be ing towed), you
w ill still be able to steer the veh icle .
However,
considerably more effort will
be required to do so .
- If the powe r steering system sho uld
have a leak, or is not functioning proper­
ly, contact your author ized Audi dealer
immediately.
- The power steering system req uires a
specially formu lated hydraulic fluid. The
power steering fluid reservoir is located
in the engine compartment
9 page 233. IJJ,,
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•

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 ..,.

temperature. This determines the current
state of charge and the power of the battery.
Idling current management
Idling current management reduces energy
consumpt ion while the vehicle is stand ing.
With the ignition switched off, it contro ls the
energy supply to the various e lectrica l compo ­
nents . Data from battery diagnosis is consid­
ered.
D epending on the battery's state of charge,
individua l consumers are gradua lly turned off
to prevent excessive discharge of the battery
and thus maintain starting capability.
Dynamic energy management
While the veh icle is being driven, dynamic en­
ergy management dist ributes the energy gen­
erated according to the needs of the individu­
a l components . It regu lates consumption, so
that more electrical energy is not being used
than is being generated and ensures an opti­
mal state of charge for the battery.
- But even energy management cannot negate the limits of physics. Consider
that the power and life of a battery are
limited.
- If starting ab ility is threatened, the indi­
cator light(•) appears
c> page 16, D
Battery.
What you should know
The highest priority is given to maintaining
starting capability .
The battery is severely taxed in short-distance
driving, in city traffic and during the co ld time
of year. Abundant electrical energy is re­
qu ired, but only a little is generated. It is also
cr itica l if the engine is not running and electri­
cal components are turned on. In th is in­
stance energy is being consumed but none is
be ing generated .
Intelligent technology 205
It is in precisely these situations that you will
notice energy management active ly regu lat­
ing the distribution of energy.
Vehicle stands for an extended period
If you do not drive your vehicle over a period
of several days or weeks, e lectrica l compo­
nents are gradually cut back or switched off.
This reduces energy consumption and main­
tains starting capability over a longer period .
Some of the convenience functions may not
operate, such as the interior lights or the
power seat adjustment . The convenience
functions will be available again when you
switch on the ignition and start the eng ine.
With the engine turned off
If you listen to the radio, for example, with
the engine turned off or use other MMI func­
tions, the battery is being discharged.
If starting capability is jeopardi zed due to en­
ergy consumption, the following warning ap­
pears in the MM I display:
Please start the engine soon or the system
will be turned off.
The warning indicates that the system will be
turned off automatically after 3 minutes. If
you w ish to continue using the functions, you
have to start the engine.
With the engine running
Although electrical energy is generated when
the vehicle is being driven, the battery can be­
come discharged. This happens mostly when
li ttle energy is being generated and a great
deal consumed and the battery's state of
charge is not optimal.
T o b ring the energy ba lance back into equili­
brium, consumers wh ich requ ire espe cially
large amounts of energy are temporarily cut
back or switched off . Heating systems in par­
ticular require a great deal of energy. If you
notice, for examp le, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched .,.
•
•