ESP AUDI S4 CABRIOLET 2009 Service Manual

-Driving Safely
_---:;.._----=------------------
and strikes
an occupant who is not in the proper seating
position. A driver is responsible for the safety of all vehicle
occupants and especially for children. Therefore:
Never allow anyone to assume an incorrect seating posi ­
tion when the vehicle is being used~&, .
The following bullets list only some sample positions that will
increase the risk of serious injury and death. Our hope is that these
examples will make you more aware of seating positions that are
dangerous.
Therefore, whenever the vehicle is moving: • never stand up in the vehicle
• never stand on the seats
• never kneel on the seats
• never ride with the seatback reclined
• never lie down on the rear seat
• never lean up against the instrument panel
• never sit on the edge of the seat
• never sit sideways
• never lean out the window
• never put your feet out the window
• never put your feet on the instrument panel
• never rest your feet on the seat cushion or back of the seat
• never ride in the footwell
• never ride in the cargo area
& WARNING
Improper seating positions increase the risk of serious personal
injury and death whenever a vehicle is being used.
& WARNING (continued)
• Always make sure that all vehicle occupants stay in a proper
seating position and are properly restrained whenever the vehicle
is being used . •
Driver and passenger side footwell
Important safety instructions
& WARNING
Always make sure that the knee airbag can inflate without inter­
ference. Objects between yourself and the airbag can increase the risk of injury in an accident by interfering with the way the airbag
deploys or by being pushed into you as the airbag deploys.
• No persons (children) or animals should ride in the footwell in
front of the passenger seat.
If the airbag deploys, this can result in
serious or fatal injuries .
• No objects of any kind should be carried in the footwell area in
front of the driver's or passenger's seat. Bulky objects (shopping
bags, for example) can hamper or prevent proper deployment of
the airbag. Small objects can be thrown through the vehicle if the
airbag deploys and injure you or your passengers. •
Pedal area
Pedals
The pedals must always be free to move and must never
be interfered with by a floor mat or any other object.
Make sure that all pedals move freely without interference and that
nothing prevents them from returning to their original positions.
~

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- Alw ay s place an d prop erly secure h eavy items in the
luggage com partm en t as fa r fo rwa rd as possi ble.
& WARNING
Improperly stored luggage or other items can fly through the
vehicle causing ser ious personal injury in the event of hard br aking
or an a ccident. To help reduce the risk of serious personal injury :
• Always put objects , for e xample , luggage or other heavy items
in the luggage compartment.
& WARNING
Heavy loads will influence the way your vehicle handles. To help
reduce the risk of a loss of control leading to serious personal
injury :
• Always keep in mind when transporting heavy objects , that a
change in the center of gravity can also cause changes in vehicle
handling:
-Always distribute the load as e venly as possible .
- Place heavy objects as far forward in the luggage compart -
ment as possible .
• Never exceed the Gross Axle Weight Rating or the Gros s
Vehicle Weight Rating specified on the safety compliance sti cker
on the left door jamb. Exceeding permis sible weight standards
c an cau se the veh icle to slide and handle differently .
• Please ob serve information on safe driving:::::,
page 146.
& WARNING
To help prevent poisonous exhaust gas from being dra wn into the
vehicle , always keep the rear l id clo sed while driv ing.
• Ne ver t ransport obje cts larger than those fitting completely
into the luggage area because the rear lid cannot be fully closed.
& W ARNING (continued )
• If you absolutely must drive with the rear lid open, observe the
following notes to reduce the risk of poisoning :
- Close all windows ,
- Close the power top ,
- Open all air outlets in the instrument panel ,
- Switch off the air recirculation ,
- Set the fre sh air fan to the highest speed .
& WARNING
Always make sure that the doors, all windows , the power roof and
the rear lid are securely closed and locked to reduce the ri sk of
injury when the vehicle is not being used.
• After closing the rear lid , always make sure that it i s properly
closed and locked .
• Never leave your vehicle unattended especially with the rear lid
left open. A child could crawl into the vehicle through the luggage
compartment and close the rear lid becoming trapped and unable
to get out . Being trapped in a vehi cle can le ad to serious personal
injury.
• Never let ch ildren play in or around the vehicle.
• Never let pa ssengers ride in the luggage compartment . Vehicle
occupants must always be properly restrained in one of the
vehicle's seating po sition s.
[ i ] Tips
• Air circu lat io n helps to reduce window fogg in g when the power
top is c losed. Stale air escapes to the outside through slots in the
t rim pa nels o n both sides of the luggage co mpartment. Make sure
that these s lots are not b locked. _.

• The tire pressure must correspond to the load -see the tire pres ­
s ur e s tick er on d river 's s ide B-p ill ar o r insid e t he f uel fill er fla p.•
Reporting Safety Defects
Applicable to U.S.A.
If you believe that your vehicle has a defect
which could cause a crash or could cause injury or death, you should immediately inform
the National Highway Traffic Safety Adminis­
tration (NHTSA) in addition to notifying Audi of
America, Inc.
If NHTSA re ceives similar complaints, it may
open an investigation, and if it finds that a
safety defects exists in a group of vehicles , it
may order a recall and remedy campaign.
However , NHTSA cannot become involved in
individual problems between you , your dealer,
or Audi of America , Inc.
To contact NHTSA , you may call the Vehicle
Safety Hotline toll -free at:
Tel.: 1 -888 -327 -4236 (TTY: 1 -800 -424 -9153)
or write to:
Admini strator
NHTSA
1200 New Jersey Avenue , SE
Controls and equip­
ment Safety first Vehicle operation
Driving Safely 1111
Washington
, D.C. 20590
You can also obtain other information about motor vehicle safety from:
http: //www.safercar.gov
Applicable to Canada
Canadian customers who wish to report a
safety -related defect to Tran sport Canada ,
Defect Investigations and Recall s, may tele­
phone the toll free hotline:
Tel.: 1 -800 -333 -0371
or conta ct Transport Canada by mail at:
Road Safet y and Moto r Veh icle Regulation
Directorate
Transport Canada
Tower C, Place de Ville, 330 Sparks Street
Ottawa, ON K1 A 0N5
For additional road safety information , please
vi sit the Road Safety web site at:
http:/ /www.tc.gc.ca /roadsafety /menu.htm •
Vehicle care Do-it-yourself service Technical data

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Safety belts
General notes
Always wear safety belts!
Wearing safety belts correctly saves lives!
This chapter explains why safety belts are necessary, how
they work and how to adjust and wear them correctly.
- Read all the information that follows and heed all of the
instructions and WARNINGS.
& WARNING
Not wearing safety belts or wearing them improperly increases
the risk of serious personal injury and death.
• Safety belts are the single most effective means available to
reduce the risk of serious injury and death in automobile acci­
dents. For your protection and that of your passengers, always
correctly wear safety belts when the vehicle is moving.
• Pregnant women, injured, or physically impaired persons must
also use safety belts . Like all vehicle occupants, they are more
likely to be seriously injured if they do not wear safety belts. The
best way to protect a fetus is to protect the mother -throughout
the entire pregnancy. •
Number of seats
Your vehicle has a total of four seating positions : two in the front
and two in the rear. Each seating posi tion has a safety belt .
Controls and equip­ ment Safety first
Vehicle operation
& WARNING
Not wearing safety belts or wearing them improperly increases
the risk of serious personal injury and death.
• Never strap more than one person, including small children,
into any belt. It is especially dangerous to place a safety belt over
a child sitting on your lap.
• Never let more people ride in the vehicle than there are safety
belts available.
• Be sure everyone riding in the vehicle is properly restrained
with a separate safety belt or child restraint. •
Safety belt warning light ~
Your vehicle has a warning system to remind you about
the importance of buckling-up.
Before driving off, always:
Fig. 161 Safety belt
warning light in the
instrument cluster ·
enlarged
- Fasten your safety belt and make sure you are wearing it
properly. .,
Vehicle care Do-it-yourself service Technical data

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Improperly worn safety belts
Incorrectly positioned safety belts can cause severe inju­
nes.
Wearing safety belts improperly can cause serious injury or
death. Safety belts can only work when they are correctly positioned on the body. Improper seating positions reduce
the effectiveness of safety belts and will even increase the
risk of injury and death by moving the safety belt to critical
areas of the body. Improper seating positions also increase
the risk of serious injury and death when an airbag deploys
and strikes an occupant who is not in the correct seating
position . A driver is responsible for the safety of all vehicle
occupants and especially for children. Therefore:
- Never permit anyone to assume an incorrect sitting posi­
tion in the vehicle while traveling=>&.
& WARNING
Improperly worn safety belts increase the risk of serious personal
injury and death whenever a vehicle is being used.
• Always make sure that all vehicle occupants are correctly
restrained and stay in a correct seating position whenever the
vehicle is being used.
• Always read and heed all WARNINGS and other important infor­
mation
=> page 162. •
Safety belt pretensioners
How safety belt pretensioners work
In front, side and rear-end collisions above a particular
severity, safety belts are tensioned automatically.
The safety belts are equipped with safety belt pretensioners . The
system is activated by sensors in front, side and rear -end collisions
of great severity . This tightens the belt and takes up belt slack=>&.
in "Service and disposal of safety belt pretensioner" on
page 167.
Taking up the slack helps to reduce forward occupant movemen t
during a collision.
[ i] Tips
The safety belt pretensioner can only be activated once.
• In minor frontal and side collisions , in rear-end collisions, in a
rollover and in accidents involving very little impact force, the safety
belt pretension er are not activated.
• When the safety belt pretensioners are activated, a fine dust is
released. This is normal and is not caused by a fire in the vehicle.
• The relevant safety requirements must be observed when the
vehicle or components of the system are scrapped . A qualified deal­
ership is familiar with these regulations and will be pleased to pass
on the information to you.
• Be sure to observe all safety, environmental and other regula ­
tions if the vehicle or individual parts of the system, particularly the
safety belt or airbag, are to be disposed. We recommend you have
your authorized Audi dealer perform this service for you. •

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Airbag system
Important things to know
Importance of wearing safety belts and
sitting properly
Airbags are only supplemental restraints. For airbags to
do their job, occupants must always properly wear their
safety belts and be in a proper seating position.
For your safety and the safety of your passengers, before
driving off, a lways:
- Adjust the driver's seat and steering wheel properly
=>
page 148,
- Adjust the front passenger's seat properly => page 93,
- Wear safety belts properly=> page 162,
- Always properly use the proper child restraint to protect
children=>
page 190 .
In a collision airbags must inflate within the blink of an eye and with
considerable force . Th e suppl emental airbags can caus e injuries if
the driver or the front seat passenger are not seated proper ly . There ­
fore in order to help the airbag to do its job, it is impor tant, both as
a driver and as a passenger to sit properly at all times.
By keeping room between your body and the steering wheel and the
front of the passenger compartment, the airbag can inflate fully and
completely and prov ide supplementa l protection in certain frontal
collisions ~
page 148, "Proper occupant seating positions" . For
details on the operation of the seat adjustment controls~
page 93
and ~ page 96.
It's especially important that chi ldren are proper ly restrained
~ page 190.
There is a lot that the driver and the passengers can and must do to
help the individual safety features installed in your Audi work
together as a system.
Proper seating posi tion is important so that the front airbag on the
driver side can do its job. If you have a physical impairment or
condition that prevents you from sitting properly on the driver seat
with the safety belt properly fastened and reaching the pedals, or if
you have concerns with regard to the function or operation of the
Advanced Airbag System, please contact your authorized Audi
dea ler or qua lif ied workshop, or call Audi Customer CARE at 1-800 -
822 -2834 for possible modifications to your vehicle .
When the airbag system deploys, a gas generator wi ll fill the
airbags, break open the padded covers, and inflate between the
steering wheel and the driver and between the instrument panel
and the front passenger. The airbags will deflate immediately after
deployment so that the front occupants can see through the wind ­
shield again without interruption .
All of this takes p lace in the blink of an eye, so fast that many people
don't even rea lize that the airbags have dep loyed. The airbags also
inflate with a great deal of force and nothing should be in their way
when they deploy . Front airbags in combination with properly worn
safety bel ts slow down and limit the occupant's forward movement.
Together they help to prevent the driver and front seat passenger
from hitting parts of the inside the vehicle while reducing the forces acting on the occupant during the crash . In this way they help to
reduce the risk of injury to the head and upper body in the crash .
Airbags do not protect the arms or the lower parts of the body.
Both front airbags w ill not in flate in al l frontal collisions . The trig ­
gering of the airbag system depends on the vehic le deceleration
rate caused by the collision and registered by the electronic contro l
unit. If this rate is below the reference value programmed into the
control unit, the airbags will not be triggered, even though the car
may be badly damaged as a result of the collision . Vehicle damage, .,

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Child restraints on the front seat - some
important things to know
- Be sure to read the important information and head the
WARNINGS for important details about children and
Advanced Airbags~
page 190.
Even though your vehic le is equipped with an Advanced Airbag
System, make certain that a ll children, especia lly those 12 years and
younger, a lways ride in the back seat properly restrained for their
age and size . The airbag on the passenger side makes the front seat
a potentia lly dangerous place for a child to ride. The front seat is not
the safest p lace for a chi ld in a forward -facing child safety seat. It
can be a very dangerous place for an infant or a child in a rearward ­
facing seat.
The Advanced Airbag System in your vehicle has been certified to
comply with the Requirements of United States Federal Motor
Vehicle Safety Standard 208 as applicab le at the time your vehicle
was manufactured.
Th e Standard requires the front airbag on the passenger side to be
turned off ("suppressed") if a chi ld up to about one year of age
restrained in one of the rear-facing or forward-facing infant
restraints listed in Federa l Motor Vehicle Safety Standard 208 with
which the Advanced Airbag System in your vehicle was certified has been instal led on the front passenger seat. For a listing of the child
restraints that were used to certify compliance with the US Safety
Standard =>
page 192.
The PASSENGER AIR BAG OFF light in the instrument panel tells you
when the front Advanced Airbag on the passenger side has been
t urned off by the electronic control unit.
Each time you turn on the ignition, the
PASSENGER AIR BAG OFF
light will come on for a few seconds and:
• will stay on if the front passenger seat is not occupied, •
will stay on if there is a small child or child restraint on the front
passenger seat,
• will go off if the front passenger seat is occupied by an adult as
registered by the weight-sensing mat=>
page 179, "Monitoring the
Advanced Airbag System" .
The
PASSENGER AIR BAG OFF light comes on when the control unit
detects a tota l weight on the front passenger seat that requires the
front airbag to be turned off.
If the total weight on the front passenger seat is more than that of
a typical 1 year -old child but less than the weight of a small adult,
the fron t airbag on the passenger side can deploy (the
PASSENGER
AIR BAG OFF
light does not come on). If the PASSENGER AIR BAG
OFF
light does not come on, the front airbag on the passenger s ide
has not been turned off by the electronic contro l unit and can
deploy if the control unit senses an impact that meets the condi ­
tions stored in its memory.
For example, the airbag may deploy if:
• a small ch ild that is heavier than a typical 1 year-o ld child is on
the front passenger seat (regardless of whether the child is in one
of the child safety seats listed =>
page 192), or
• a child who has outgrown chi ld restraints is on the front
passenger seat .
If the front passenger airbag is turned off, the
PASSENGER AIR BAG
OFF
light comes on in the instrument cluster and stays on.
The front airbag on the passenger side may
not deploy (the
PASSENGER AIR BAG OFF light does not illuminate and stay lit) even
if a small adult or teenager, or a passenger who is not sitting upright
with their back against a non -reclined backrest with their feet on the
vehicle floor in front of the seat is on the front passenger seat
=>
page 148, "Proper seating position for the driver".
If the front passenger airbag deploys, the Federal Standard requires
the airbag to meet the "low risk" deployment criteria to reduce the
risk of injury through interaction with the airbag. "Low risk" deploy­
ment occurs in those crashes that take p lace at lower decelerations .,.

-Airbag system --=----=----------------
& W
ARNING (continued )
• Improper installation of child restraints can reduce their effec­
tiveness or even prevent them from p roviding any protection .
• An improperly installed child restraint can interfere with the
airbag as it deploys and seriously injure or even kill the child -
even with an Advanced Airbag System .
• Always carefully follow the manufa cturer's instru ctions
provided with the child safety seat or carrier .
• Never place additional items on the seat that can increase the
total weight registered by the weight-sensing mat and can cause injury in a crash .
LJ
Front airbags
Description of front airbags
The air bag sy stem can provi de su ppleme ntal pr ote ct io n
to prope rly r estrai ned fron t se at occu pants.
Fig. 1 7 1 L ocation of
driver airbag: in
s teeri ng w heel
Fig . 172 Location of
fron t pa ssenger' s
airbag : in the in stru ­
ment panel
Your vehicle is equipp ed with an " Advanced Airbag System" in
complia nce wit h United States Federal Motor Vehicle Safe ty Stan ­
dard (FMVSS) 208 as appl icab le at the time your veh icle was manu ­
f act ured. The safety bel ts for the front seat s have "pretensi one rs"
t ha t help to take slack ou t of the be lt s ystem. The p re tens io ne rs a re
also activated by the electronic control unit for the airbag system.
The fr ont safe ty belts als o h ave loa d lim iters to hel p reduce the
forces applied to the body in a crash.
The a irbag f or the driver is i n the st eeri ng wheel hub~ fig. 171 a nd
t h e airbag for the front passenger is in the i nstrument panel
~ fig. 172. The genera l location of the airbags is marked "AIRBAG".
There is a lot you need to know ab out t he airbags in y our vehicle. We
u rge you to read the deta iled information about airbags, safety belts
and child s afety i n th is and th e other c ha pt ers t hat make u p the
owner's literature. Please be sure to heed the WARN INGS -they are
e xt reme ly im portan t for y our safe ty a nd the safe ty of y our passen ­
gers, especia lly infants and small childr en.
& WARNING
Never rely on airbags alone for protection .
• Even when they deploy, airbags provide only supplemental
protect ion .

Airbag syst em -----------------=~-
& WARNIN G (cont in u ed)
• Airb ag work m ost effectiv ely when u sed with properly worn
sa fet y be lt s .
• Ther efore , always wear your safety belt s and ma ke sure that
eve rybod y in your vehi cle is prope rly re str ained.
& WARNING
A person on the front p assenger se at, espe cially infant s and small
c hildren , will re ceive seriou s injuries and can ev en be killed by
being t oo clos e to the airbag when it infl ates.
• Although the Adva nced Airbag System in your ve hicle i s
de signed to turn off the front passenger airb ag i f a n infant or a
s mall child i s on the front pa ssenger seat , nobody can absolutely
gu ara ntee that deployment under these spe cial co nditio ns is
impos sible in all conceivable situations that m ay happen during
the useful life of your vehicle.
• The Adv an ced Airbag Sy stem can deploy in a ccordance with
the "lo w risk" option unde r the U .S. Feder al Stand ard if a child t hat
is heavier than the typi cal on e-year old child i s on th e front
pa sse nger seat an d the other condition s for airb ag dep loym ent
are met.
• Acc ident stat istics have sh own that children are gen erally s afer
in the rear se at area than in the front seating posit ion .
• For th eir own safet y, all children , espe cially 12 yea rs and
younger , should alway s ride in th e back properly r estrained for
their age and size. •
Advanced front airbag system
Your vehicle is equipped with a front Advanced Airbag System in
compliance with United States Federal Motor Vehicle Sa fety Stan ­
dard 208 as applicable at the time your vehicle was manufactured.
Controls and equip­
ment Safety first Vehicle operation
The front Advanced Airbag System supplements the safety belts to
provide additional protection for the driver's and front passenger's
heads and upper bodies in frontal crashes. The airbags inflate only
in frontal impacts when the vehic le deceleration is high enough.
The front Advanced Airbag System for the front seat occupants is not a substitute for your safety belts . Rather, it is part of the overall
occupant restraint system in your vehicle. A lways remember that
the airbag system can only help to protect you, if you are sitting
upright, wear ing your safety be lt and wear ing it proper ly . This is why
you and your passengers must a lways be properly restrained, not
just because the law requires you to be .
The Advanced A irbag System in your veh ic le has been certified to
meet the "low risk" requirements for 3 and 6 year -o ld children on the
passenger side and very small adults on the driver side. The low risk
deployment criteria are intended to he lp reduce the risk of injury
through interact ion with the front airbag that can occur, for
examp le, by being too close to the steering whee l and instrument
panel when the airbag inflates.
In addition, the system has been certified to comply with the
"suppression" requirements of the Safety Standard, to turn off the
front airbag for infants 12 months old and younger who are restrained on the front passenger seat in child restraints that are
listed in the Standard~
page 192, "Child restraints and Advanced
Airbags".
"S uppression" requi res the front ai rbag on the passenger side to be
turned off if:
• a child up to about one year of age is restrained on the front
passenger seat in one of the rear-facing or forward-facing infant
restraints listed in Federal Motor Vehicle Safety Standard 208 with
wh ich the Advanced Airbag System in your vehicle was certified. For
a listing of the child restraints that were used to certify your
vehic le's compliance wi th the US Safety Standard ~
page 192,
• weight less than a threshold leve l stored in the control unit is
detected on the front passenger sea t. _.
Vehicle care Do-it-yourself service Technical data

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or the lower parts of t he body. Front airbags on ly supp lement the
th ree p oint safe ty belts in s ome front al c olli sio ns in which the
vehic le dece leration is high enou gh to deploy th e airbags .
Front airbags will not deploy:
• if the ignition is switched off when a crash occ urs,
• i n sid e coll is ions ,
• i n rea r- e nd collisi ons ,
• in rollovers,
• when th e c ras h de cele rat io n measu red by th e airba g sys tem is
l ess than the minimum threshold needed for a irbag deplo yment as
r egi stere d by t he ele ctr onic con trol unit.
The front passenger airbag will also not deploy :
• whe n t he fr ont pass enge r sea t is not occup ied,
• when the weight on the front passenger seat as sensed by the
A dvanced A ir b ag Sys te m in d ica tes th at the fr ont airba g on the
p assenge r side has to be t urned off b y the e lectronic cont rol unit
(t he
PASSENGER AIR BAG OFF ligh t com es o n an d stays o nl.
& WARNING
Sitting in the wrong posit ion can increase the risk of serious injury
in crashes .
• To reduce the risk of injury when the airbags inflate , the driver
and passengers must always sit in an upright position , must not
lean against or place any part of the ir body too close to the area
where the airbags are located.
• Occupants who are unbelted , out of posit ion or too close to the
airbag can be seriously injured by an airbag as it unfolds with
great force in the blink of an eye:::::,
page 170 .
& WARNING
A child in a rearward-facing child safety seat installed on the front
passenger seat will be seriously injured and can be killed if the
front airbag inflates - even with an Advanced Airbag System .
• The inflating airbag will hit the child safety seat or infant
carrier with great force and will smash the child safety seat and
child against the backrest , center arm rest , door or roof.
• Always install rear-facing child safety seats on the rear se at.
• If you must install a rearward facing child safety seat on the
front passenger seat because of exceptional circumstances and
the PASSENGER AIR BAG OFF light does not come on and stay on, i mmediately install the rear-facing child safety seat in a rear
seating position and have the airbag system inspected by your
Audi dealer .
& WARNING
Objects between you and the airbag will increase the risk of injury
in a crash by interfering with the way the airbag unfolds or by
being pushed into you as the airbag inflates .
• Never hold things in your hands or on your lap when the vehicle
is in use.
• Never transport items on or in the area of the front passenger
seat. Objects could move into the area of the front airbags during
braking or other sudden maneuver and become dangerous projec ­
tiles that can cause serious personal injury if the airbags inflate .
• Never place or attach accessories or other objects (such as cup
holders , telephone brackets , large, heavy or bulky obje cts) on the
doors , over or near the area marked "AIRBAG" on the steering
wheel, instrument panel , seat backrests or between those areas
and yourself . These objects could cause injury in a crash, espe­
cially when the airbags inflate .
• Never recline the front passenger's seat to transport objects .
Items can also move into the area of the side airbag or the front ..,