2013 AUDI A8 steering

166 Airbag sys te m
removing, servicing or repairing a part in an
area of the vehicle can damage a part of an
a ir bag system and prevent that system from
working properly in a co llision.
There are some important things you have to know to make sure that the effectiveness of
the system will not be impa ired and that dis­
carded components do not cause injury or pol­ lute the env ironment.
A WARNING
Improper care, servicing and repair proce­
dures can increase the risk of personal in­
jury and death by preventing an airbag from deploy ing when needed or deploying
an airbag unexpectedly:
- Never cover, obstruct, or change the
steering wheel horn pad or airbag cover
or the instrument pane l or modify them
in any way.
- Never attach any objects such as cup
holders or telephone mountings to the
surfaces covering the airbag units.
- For deaning the horn pad or instrument
pane l, use only a soft, dry cloth or one
moistened with plain water. Solvents or
cleaners cou ld damage the airbag cover
or change the stiffness or strength of the
material so that the airbag cannot de­
ploy and protect properly.
- Never repa ir, adjust, or change any parts
of the airbag system .
- All work on the steering wheel, instru­
ment pane l, front seats or electrical sys­
tem (including the installation of audio
equipment, cellular telephones and CB
radios, etc .) must be performed by a
qualified technician who has the training
and special equipment necessary.
- For any work on the airbag system, we
strongly recommend that you see your
authorized Audi dealer or qualified work­ shop.
- Never modify the front bumper or parts
of the veh icle body.
- Always make su re that the side airbag
can inflate without interference: -
Never install seat covers or rep lace­
ment upholstery over the front seat­
backs that have not been specifically
approved by Audi.
- Never use additional seat cushions that
cover the areas where the side airbags
inflate.
- Damage to the orig inal seat covers or
to the seam in the area of the side air­
bag module must a lways be repaired
immediately by an author ized Audi
dealer.
- The airbag system can be activated only
once. After an airbag has inflated, it
must be replaced by an authorized Aud i
dealer or qualified technician who has
the technical information, training and
specia l equipment necessary .
- The airbag system can be deployed only
once. After an airbag has been deployed,
it must be replaced with new replace­
ment parts designed and approved espe­
cially for your Audi model version. Re­
placement of complete airbag systems
or airbag components must be per­
formed by qualified workshops only. Make sure that any airbag serv ice action
is entered in your Audi Warranty
& Main­
tenance booklet under
AIRBAG REPLACE­
MENT RECORD.
- For safety reasons in severe accidents,
the alternator and starter are separated
from the vehicle battery with a pyrotech­
nic circuit interrupter.
- Work on the pyrotechnic c ircuit inter­
rupter must only be performed by a
qualified dea ler -risk of an accident!
- If the vehicle or the circuit interrupter
is scrapped, all applicable safety pre­
cautions must be followed.
® For the sake of the environment
Undeployed airbag modules and preten­
s ioners might be classif ied as Perchlorate
Material -special handling may apply, see
www .dtsc .ca.gov/hazardouswaste/per­
ch lorate. When the veh icle or parts of the
rest raint system including airbag modu les .,.

and safety belts with pretensioners are
scrapped, all applicable laws and regula­
tions must be observed. Your authorized
Audi dealer is familiar with these require­
ments and we recommend that you have
your dealer perform this service for you .
Other things that can affect Advanced
Airbag performance
Changing the vehicle's suspension system can
change the way that the Advanced Airbag Sys­
tem performs in a crash. For example, using
tire-rim combinations not approved by Audi,
lowering the vehicle, changing the stiffness of
the suspension, including the springs, suspen­
sion struts, shock absorbers etc. can change
the forces that are measured by the airbag
sensors and sent to the electronic control
unit. Some suspension changes can, for exam­ ple, increase the force levels measured by the
sensors and make the airbag system deploy in
crashes in which it would not deploy if the
changes had not been made. Other kinds of
changes may reduce the force levels meas­
ured by the sensors and prevent the airbag
from deploying when it should.
The sensors in the safety belt buckle for the
driver and front passenger seat tell the elec­
tronic control module if the safety belt is
latched or not. If the safety belt is being used,
the front airbag will deploy at a slightly high­
er rate of vehicle deceleration than if the safe­
ty belt is not being used. Therefore, in a par­
ticular collision, it is possible that an airbag
will not deploy at a seating position where the safety belt is being used but will inflate at the
position where the safety belt is not being
used . It is important that nothing interfere
with the safety belt buckles so that the sen­
sors can send the correct information about
safety belt use to the electronic control unit.
A WARNING
Changing the vehicle's suspension includ­
ing use of unapproved tire-rim combina­
tions can change Advanced Airbag per-
Airbag system 167
formance and increase the risk of serious
personal injury in a crash.
- Never install suspension components
that do not have the same performance characteristics as the components origi­nally installed on your vehicle.
- Never use tire-rim combinations that have not been approved by Audi.
A WARNING
Items stored between the safety belt buckle and the center console can cause
the sensors in the buckle to send the
wrong information to the e lectronic con­
trol module and prevent the Advanced Air­
bag System from working properly.
- Always make sure that nothing can inter­
fere with the safety belt buckles and that
they are not obstructed.
Knee airbags
Description of knee airbags
The knee airbag system can provide supple­
mental protection to properly restrained
front seat occupants.
Fig . 169 Driver 's knee airbag
The driver knee airbag is in the instrument
panel underneath the steering wheel
¢ fig . 169, the airbag for the passenger is at
about the same height in the instrument pan­
el underneath the glove compartment.
The knee airbag offers additional protection
to the driver 's and passenger's knees and up­
per and lower thigh areas and supplements
the protection provided by the safety belts.
Ill-

How knee airbags work
The risk of injury to the leg area con be re­
duced by fully inflated knee airbags.
Fig. 170 Inflated airbags protecting in a fro ntal coll i­
sio n
The knee airbag system has been designed so
that the airbags for the driver and front pas­
senger deploy in certain but not all frontal
collisions .
If the front airbags deploy, the knee airbags
also deploy in frontal collisions when the de­
ployment threshold stored in the control unit
is met .
When the system deploys, the airbags fill
with a propellant gas, and inflate between the
lower part of the instrument panel and the
driver and the lower part of the instrument
panel and the front passenger~
page 161,
fig . 167.
Although they are not a soft pillow, they can
"cush ion" the impact and in this way they can
help to reduce the risk of injury to the lower
extremities.
All of this takes place in the blink of an eye, so
fast that many people don't even realize that
the airbags have deployed . The airbags also
inflate with a great deal of force and it is im­
portant for occupant safety that nothing
should be in their way when they deploy.
Fully inflated airbags in combination with
properly worn safety belts slow down and lim­
it the occupant's forward movement and help
to reduce the risk of injury.
Airbag system 169
Important safety instructions on the
knee airbag system
Airbags ore only supplemental restraints . Al­
ways wear safety belts correctly and ride in a
proper seating position .
There is a lot that you and your passengers
must know and do to help the safety belts and
airbags to provide supplemental protection.
_& WARNING
An inflating knee airbag can cause serious injury. Wearing safety belts incorrectly and
improper seating positions increase the
risk of serious personal injury and death
whenever a vehicle is being used.
- The knee airbag system cannot protect
you properly if you a re seated too close
to any of the airbag locations. When ad­
justing their seat positions, it is impor­
tant that both the driver and the front
passenger keep their upper bodies and
knees at the following minimum safe
distances:
- at least 10 inches (25 cm) between the
chest and the steering wheel/instru­
ment panel.
- at least 4 inches (10 cm) between the
knees and the lower part of the instru­
ment panel.
- The risk of personal injury increases if
you lean forward or to the side, or if the
seat is improperly positioned and you are not wearing your safety belt. The risk in­
creases even more should the airbag de­ ploy.
- Always make sure that the knee airbag
can inflate without interference. Objects
between you and the airbag can increase
the risk of injury in an accident by inter­
fering with the way the airbag deploys or
by being pushed into you as the airbag
deploys.
- Never let anybody, especially children
or animals ride in the footwell in front

-Always install rear-facing child safety
seats on the rear seat.
- If you must install a rearward facing
child safety seat on the front passenger
seat in exceptional circumstances and
the
PASSENGER AIR BAG OFF light does
not come on and stay on, immediately
install the rear-facing child safety seat in
a rear seating position and have the air­
bag system inspected immediately by
your Audi dealer.
_& 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 a front "Ad­
vanced Airbag System" in compliance with United States Federal Motor Vehicle Safety
Child Safety 177
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, all children, espe­ cially those 12 years and younger, should al­
ways ride in the back seat properly restrained
for their age and size. The airbag on the pas­
senger side makes the front seat a potentially dangerous place for a child to ride . The front
seat is not the safest place for a child in a for­
ward-facing child safety seat. It can be a very
dangerous 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 ..,.
•
•

198 Intellige nt tec hno logy
Intelligent technology
Notice about data
recorded by veh ic le
control modules
Your vehicle is not equipped with an Event Da­
ta Recorder (EDR), installed by some manu­
facturers fo r 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 retrieval 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.
A lthough 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 example, engine function, emis­
sion control, as well as for the airbags and
safety belts.
These electronic control modules also record
vehicle-related data during normal 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 well 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 Stab ilization
Control (ESC)
Description
ESC helps to improve road holding and vehicle
dynamics to help reduce the probability of
skidding and loss of vehicle control. It works
only when the engine is running. ESC detects certain difficult driving situations, including
when the vehicle is beginning to spin (yaw)
out of control and helps you to get the vehicle back under control by selectively braking the
wheels, and/or reducing engine power and
providing steering assistance to help hold the
vehicle on the driver's intended course. The in­
dicator light
G) 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 a ll cond itions 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 towing a trailer.
Always 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 inattent ion. Instead, ESC improves the
possibility of keeping the vehicle under con­
trol and on the road during 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.

ESC includes and/or works together with the
anti-lock braking system (ABS), brake assist
system, anti-s lip regulat ion (ASR), electronic
d ifferential lock (EDL), dynamic steering* and
electronic interaxle differential lock*. ESC is
sw itched on all the time . In certain s ituations
when you need less tract ion, you can sw itch
off ASR by pressing the button above
~ page 200, fig. 188 the se lector lever. Be
sure to sw itch ASR o n aga in when yo u no lon­
ger need less traction.
Anti -lock braking system (ABS)
ABS prevents the wheels from locking up
when braking. The veh icle can still be steered
even du ring ha rd b raking . Apply steady p res­
sure to the brake pedal. Do not p ump the ped­
a l. A pulsing in the brake peda l indicates that
the system is he lping you to brake the vehicle .
Brake as sist system
The brake assist system can decrease bra king
d istance.
It increases braking power when the
driver presses the brake pedal qu ick ly in eme r­
gency situations . You must p ress and ho ld the
brake peda l until the situation is over. In
vehicles with adaptive cruise control*, the
brake assist system is more sensit ive if the
d istance detected to the vehicle ahead is too
small.
Anti- slip regulati on (A SR )
ASR reduces engine power when the drive
wheels begin to spin and adapts the force to the road condit ions. This makes it eas ier to
start, accelerate and drive up hills.
Electronic 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 75 mph (120 km/h).
In extreme cases, EDL automatica lly switches
off to help keep the brake on the braked whee l
from overheating. EDL w ill switch on again au­
tomatically when conditions have returned to normal.
Int ellig ent technolog y 199
Dynamic ste ering *
On vehicles with dynam ic steering, ESC helps
stabilize the steering in certain situations.
Electronic intera xle differential l ock
function*
T he electron ic i nteraxle differential lock f unc ­
tion activa tes when dr iving th ro 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 elect ronic interaxle differential
loc k function* cannot ove rcome the laws
of physics. This is espec ially important
on slippery or we t roads.
If the systems
begin acting to stabilize your veh icle, 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 contro l, collision and ser ious per­
sonal injur ies.
- Always adapt your speed to road, traffic and weather conditions. The risk of los­ing con trol of the vehicle increases when
driving too fast, espe cially through
curves a nd on slippe ry or wet roads, and
when dr iving too close to vehicles up
ahead. ESC, ABS, the brake assist sys­
tem, EDL, ASR, dynam ic steering* and
the electron ic interaxle d ifferential lock
function" cannot prevent co llisions.
- Always accelerate with spec ial care on
even, smooth surfaces 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
hicle control.
-
•
•

202 Intellig ent technol ogy
- If you damage the fro nt 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 creased stopp ing distance. Avoid driv ing
the vehicle and have it towed to the near­ est Aud i dea ler or qualified workshop .
Brake booster
The brake booster adds extra braking power .
The brake booster works with vacuum pres­
sure which is created only when the engine is
running ¢& .
& WARNING
-Never let the vehicle ro ll to a stop w ith
the engine shut off.
- If the brake booster is not work ing, for
example when towing your vehicle, 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
system senses the road speed and e lectroni­
cally adjusts powe r ass istance to p rov ide com ­
fortable and sa fe stee ring response exactly
matc hed to the ve hicle speed .
Power steering w il l not work if the eng ine is
off . As a result, the steering whee l w ill be hard
to turn.
The power steering fluid level is chec ked dur­
ing the scheduled ma intenance serv ices.
(D Note
If there is an e lectronic malfunction, ser­
votronic
will still function like a conven­
tiona l power steering system, providing a
constant steering support force that is no
l onger proportionate to the vehicle speed.
This is most not iceable when t urning the
steering wheel at low speeds (for example
when pa rking), - more effort w ill be re­
q uired than us ual.
- Be aware of the diffe rent than usual
steering response and adjust your steer­
ing force acco rding ly.
- Have the problem checked and set right
by an A udi dealer as soon as poss ible.
(D Tips
- When the eng ine is running, never ho ld
the stee ring wheel turned all the way to
the rig ht or to the left fo r longer than 15
seconds. The powe r stee ring pump will
overheat the hydraulic fluid i f yo u keep
holding the stee ring wheel turned all the
way. This is likely to damage the power steering system.
- If the powe r steering system sho uld fai l
entire ly, or if the engine is not runn ing
(for example, wh ile be ing towed), you
w ill still be able to stee r the veh icle.
However,
considerably more effort will
be requi red to do so.
- If the power steering system should
have a leak, or is not functioning proper­
ly, contact your author ized Audi dealer
immed iately.
- The power steer ing system req uires a
specially fo rmu lated hyd raulic fluid. The
powe r stee ring fluid reservoir is located
in the engine comp art ment¢
page 234.
T he cor rect fluid level in the reservoir is
impo rtant fo r proper functioning of the
powe r stee ring .

212 Trailertowing
Trail er load dis tr ibut ion
Be sure the load in the trai ler is held securely
in place to prevent it from shifting forward,
backward or sideways.
N eve r all ow a p assenger to rid e in a trailer
~.&. in Driving instructions on page 213.
Engine cooling sy stem
Towing a tra iler makes the eng ine work hard­
er . It is important that the cooling system's
performance is up to the addit ional load .
Make sure that the cooling system has eno ugh
flu id.
Tir e pressure
When tow ing a tra iler, inflate the t ires of your
vehicle to the co ld tire pressure listed under
" Full load " on the label loca ted o n the dr iver's
side B-pillar (v is ible when the door is open).
I nflate trailer tires to tra iler and tire manufac­
turers' specifications.
Lights
Check to make sure both veh icle and trailer
l ights are wor king p roperly.
Safe ty chain s
Be sure tra iler safety cha ins are properly con­
nected from the trailer to the hitch on the ve ­
h icle . Leave enough slack in the chains to per­
mit turning corners . When you install safety
cha ins, make su re they w ill not drag on the
road when yo u are driving.
The chains shou ld cross under the tra iler
tongue to prevent it from dropping in case of
separat ion from the hitch .
Adjusting the Audi drive select
Make sure the vehicle is on a level surface be­
for e
hitching up the tra iler and b efor e adjust ­
ing the tongue weight . The vehicle must be i n
auto or comfort driving mode and not raised
~ page 109, ~CD .
Make sure that the vehicle is lowered . In Info ­
tainment, select:
I CARI function button > Low­
e r
control button . If you must drive under poor road conditions,
you can raise the vehicle
afte r coupling the
trailer or
a fter adjust ing the tongue we ight
~ page 111.
(D Note
-Changes in temperature or load can af­
fect the height of the vehicle .
- Always select auto or comfort mode .
Otherw ise, the tongue load specified for
your vehicle will no longer be applicable.
Driving instructions
Driving with a trailer always requires extra
core and consideration.
T o obtain the best possible hand ling of vehicle
and trailer, please note the fo llowing:
.. Do not tow a loaded t railer when you r ca r it­
self is not loaded .
.. Be especially carefu l when passing other
vehicles.
.. Observe speed limits.
.. Do not drive at the maximum permissible
speed .
.. Always apply brakes early .
.. Monitor the temperature gauge .
Weight di stribut ion
T owing a loaded trailer with an empty car re ­
su lts in a highly unstable d istribution of
weight. If this cannot be avoided, drive at very
l ow speeds only to avoid the risk of losing
steering control.
A "balanced" rig is easier to operate and con­
trol. This means that the tow vehicle should
be loaded to the extent possible and permissi­
ble , while keep ing the trailer as light as possi­
ble under the ci rcumstances. Whenever poss i­
ble , transfer some ca rgo to the luggage com ­
partment of the tow vehicle while obse rv ing
tong ue load requi rements and vehicle load ing
considerations .
Speed
The higher the speed, the more d ifficu lt it be­
comes fo r the driver to cont rol the rig. Do not
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