2009 AUDI A4 CABRIOLET steering

___ A_ ir_b _ a_ g~ s_ y_s _t _e _m _________________________________________________ _
& WARN IN G (c ontinu ed )
seating posit ion and ha ve the airb ag system inspected by your
Audi dealer .
• A t ight tether or other strap on a rearward-fa cing child restr aint
atta ched to the front pas senger se at can put too much pres sure
on the weight-sensing mat in the seat and reg ister more weight
than i s actually on the seat. The heavier weight registered can
make the system work as though an adult were on the seat and
deploy the Advanced Airbag when it must be suppre ssed causing
serious or even fatal injury to the child .
• If, in exc eptional cir cum stance s, you mu st in stall a forward ­
facing child restraint on the front passenger seat , always move the
seat into its rearmost po sition in the seat's fore and aft adjust ­
ment range , as far away from the airbag as possible . The ba ckrest
must be adjusted to an upright position. Make sure that the
PASSENGER AIR BAG OFF light comes on and stays on all the time
whenever the ignition is switched on .
& WARNING
• If the PASSENGER AIR BAG OFF light does not go out when an
adult is sitting on the front passenger seat after taking the steps
described above, make sure the adult i s properly seated and
restrained at one of the rear seating position s.
• Have the airbag system inspected by your Audi dealer before
transpo rting anyone on the front passenger seat .
[ i ] Tips
If the weight -sensing mat in the front passenger seat detects an
e m pty seat , the fron t airbag on the passenge r side will be tu rned
off, and PASSENGER AIR BAG OFF will stay on.•
Repair, care and disposal of the airbags
P arts of the airbag system are installed at many different p laces on
your Au di. Insta lli ng, removing, se rvic ing or repa iring a par t in an
area of the vehicle can damage a part of an airbag system and
p revent that system from w orking properly in a c ollisi on.
There are some important things you have to know to make sure
that the effectiveness of the system will not be impai red and that
discarded componen ts do no t cause injury or po llute t he e nv iro n­
ment .
& WARNING
Improper care , servicing and repair procedures can increase the
risk of personal injury and death by preventing an airbag from
deploying when needed or deploying an airbag unexpectedly:
• Never cover , obstruct , or change the steering wheel horn pad
or airbag cover or the instrument panel or modify them in any way .
• Never attach any objects su ch as cup holders or telephone
mountings to the surfa ces covering the airbag units .
• For cleaning the horn pad or instrument panel , use only a soft ,
dry cloth or one moistened with plain water. Solvents or cleaner s
c ould damage the airbag cover or change the st iffness or strength
of the material so that the airbag cannot deploy and protect prop­
erly .
• Never repair , adju st, or change any parts of the airbag sy stem .
• All work on the steering wheel , instrument panel, front seats or
electrical system (including the installation of audio equipment ,
cellular telephones and CB rad ios , etc .I 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 author ized Audi dealer or qualified workshop .
• Never modify the front bumper or parts of the vehicle body .

___ A_ ir_b _a_ g:-- s-=- y_s _t _e _m _________________________________________________ _
& WARNING
Item s s to red betwe en th e safe ty belt b uckle a nd th e cente r
co nso le can c au se the sen sors in the buc kle to send the wro ng
inf orm ation t o the e lec tronic c ontrol m odule and pre vent th e
Adv anced Airb ag System fr om working pr operly .
• Always make su re that n oth ing ca n int erfere with the saf ety
belt buckle s and that they ar e not ob structed.
<£> For the sake of the environment
Undeployed airbag modules and pretensioners might be c lassified
as Perchlorate Material -specia l handling may apply, see
www .dtsc.ca .gov/hazardouswaste/perchlorate. When the vehicle o r
parts of the restraint system including airbag modules safety be lts
with pretensioners are scrapped, all applicable laws and regula ­
tions must be observed . Your author ized Audi dealer is fami liar with
these requirements and we recommend that you have your dea ler
perform th is service for you. •
Knee airbags
Description of knee airbags
The airbag system can pr ovide supplemental protection
t o properly restrained fron t se at occu pants.
Fi g. 175 Dr iver's
ai rba g
The airbag for the driver is located in the instrument panel under ­
neath the steering wheel=> fig. 175, the airbag for the passenger is
at about the same height in the instrument panel underneath the
g love compartment.
The knee airbag offers additional protection to the driver 's and
passenger's knees and upper and lower thigh areas as a supple­
ment to the safety be lts.
If the front airbags deploy, the knee airbags also deploy in frontal
coll isions above a certain severity=>
page 177, "More important
things to know about front airbags".
Besides their normal safety function, safety be lts work to help keep
the driver or front passenger in position in case of a frontal collision
so that the airbags can provide protection.
The airbag system is not a substitute for your safety belt. Rather, it is part of the overall occupant restraint system in your vehicle.
Always remember that the airbag system can only help to protect
you if you are wearing your safety belt and wearing it properly. This
~

-Airbag system ----=--=---------------------------------
If the front airbags d ep loy, the kne e airbags a lso d ep loy in frontal
c oll is ions abov e a certai n s ev er ity.
Whe n the syst em is dep loy ed, the airba gs start to f ill with a prope l­
l ant gas, and inf late bet ween t he lower pa rt of the instr ument pa ne l
and the drive r and the l ower part of th e instru ment pane l a nd th e
front passenge r:::;, page
177 , fig. 173 .
A lth oug h the y are no t a s oft p illow, t hey can "cushion" th e im pact
and in this way they can help to r educe the ris k of injury to the lower
e xt remitie s.
A ll thi s takes place ins ta nta ne ous ly, so fast tha t many p eople don't
even realize that the airbags have deployed. The ai rbags a lso inf late
w it h a gre at d eal o f f orce and it is im por tant for occupa nt safety t hat
nothing sho uld be in their way when they dep loy.
Full y infla ted ai rbags i n co mbina tion wi th properl y w orn safe ty bel ts
s low down and limit the occupant's forward movement and he lp to
r e du ce t he risk .•
Important safety instructions on the knee
airbag system
Air bag s are only sup plemen tal restra ints. Alwa ys wea r
s af ety bel ts co rr e ctly and ride i n a prop er se atin g po sition .
Ther e is a lo t that you and your passe ngers must know a nd do to
he lp the safety belts and airbags to provide supp lemental protec ­
ti on .
& 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 airbag system cannot protect you properly if you are
seated too close to any of the airbag locations . When adjusting
& WARNING (continued )
their seat positions, it is important that both the driver and the
front passenger keep their upper bodies and knees at the
following minimum safe d istances :
-1 O inches (25 cm) between the chest and the steering
wheel /instrument panel .
- 4 inches (10 cm) between the knees and the lower part of the
instrument 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 r isk increases even more should the
airbag deploy .
• Always make sure that the knee airbag can inflate without
interference. 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 (shop­
ping bags , for example) can hamper or prevent proper deploy ­
ment of the airbag . Small objects can be thrown through the
vehicle if the airbag deploys and injure you or your passengers .
• Make sure there are no cracks , deep scratches or other damage
in the area of the instrument panel where the knee airbags are
located .
• If children are incorrectly seated , their risk of injury increases in
the case of an accident:::;,
page 190, "Child Safety". •

--------------------------------------------~C~ h~ il~d ~S~ a~f e~ t~ YL _III
& WA RNIN G (conti nu ed )
• Alway s install rear-facing child safety se ats on the rear seat.
• If you mu st in stall a rearw ard f acing chi ld safety seat on the
front pa ssenger seat in exc eptional cir cum stance s and the
PA SSENGER AIR BAG OFF light do es not come on and stay on,
im medi ate ly install the re ar-fa cing child safety s eat in a rear
s e ating po sit ion and h ave the airb ag sys tem inspe cted im medi ­
ately by your Audi de aler .
& WARNING
If, in exceptional circum stance s, you must in stall a forward -facing
c hild re st ra int on the fr ont p ass eng er' s s eat :
• Alway s make sure the forward -facing seat ha s been de signed
and cert ified by it s manufa cturer f or use on a front se at with a
p ass enger front and side airbag .
• Always follow the m anufacturer's instruct ions provided with
the child safety seat or carrier.
• Alway s m ove the pa ss e nger sea t into its rearm ost p osit ion in
the seat' s fo re and aft adju stment r ange , as far away from the
a irb ag as possib le before installing the child r estr aint . The b ack­
rest mu st be adju sted to an upr ight po sition.
• Alw ays ma ke sure th at the PAS SENGER AIR BAG OFF light
c ome s on and stay s on all the time whenever the ignition i s
s witched on . •
Advanced front airbag system and children
Your vehicle is equipped with an "Advanced Airbag System" in
compliance with United States Federal Motor Vehicle Sa fety Stan ­
dard (FMVSS) 208 as applicab le at the time your vehicle was manu ­
factured .
Controls and equip­
ment Safety first Vehicle operation
The Advanced Airbag system in your vehicle has been certified to
meet the " low -risk" requirements for 3 and 6 yea r- old child ren on
the passenger side and small adu lts on the driver side. The low risk
deployment c rite ria are intended to reduce the risk of injury th rough
interaction with the airbag that can occur, for example, by being too
close to the steering whee l and instrument panel when the airbag
in flates . In add ition, the system has been cert ified to comply with
the "suppression" requirements of the Safety Standard, 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 listed in the
Standard.
Even though your vehic le is equipped with an Advanced Airbag
system, all ch ildren, especially those 12 years and younger, should
a lways ride in the back seat proper ly restrained for the ir age and
s ize . The a irbag on the passenger side makes the front seat a poten­
tially dangerous p lace for a chi ld to r ide. The front seat is not the
safest place for a chi ld in a forward -facing child safety seat. It can be
a very dangerous place for an infant or a larger chi ld 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 p resence
of an infant or chi ld in a chi ld restraint on the front passenger seat
using the weight -sensing mat in the seat cushion 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 t otal weight of the ch ild and the
child safety seat and a chi ld blanket on the front passenger seat. The
weight on the front passenge r 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 seat. The weight of a child
restraint and its "footprint" vary for different kinds of child .,
Vehicle care Do-it-yourself service Technical data

-In
te llig ent tec hnolo gy --=---=-=-------------
Intelligent technology
Notice about data recorded by
vehicle control modules
Your vehicle is not equipped with an Event Data Recorder (EDRl,
installed by some manufacturers for the express purpose of
capturing data for retrieval after an accident or crash event . EDR's
are sometimes called "crash recorders" .
Some state laws restrict the retrieva l or downloading of data stored
by EDR's that were insta lled 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 electronic control modules for various vehicle systems such as, for examp le, engine function, emission control, as
we ll as for the airbags and safety belts.
T hese electronic control modules also record vehic le-rela ted da ta
during norma l ve hicle operation for diagnost ic and repair purposes .
The recording capacity of the electronic control modules is limited
to data (no sound is recorded) and only a small amount of data is
actually 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 vehic le speed, d irection,
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
down loaded with special equipment. •
Electronic Stabilization Program (ESP)
General information
The ESP improves the vehicle s tability.
I
A F ig . 19 0 Cen ter
co nsol e w ith ESP
sw itch
ESP is designed to he lp you maintain vehic le control in situa tions
where the car approaches the limits of "grip", especially when acce lerating and cornering . ESP reduces the risk of skidding and
improves stability under all road conditions .
The syst em opera tes across the en tire speed range in combination
with the ABS system. If the Anti-Lock Brake System (ABS) malfunc ­
tions, the ESP wil l a lso shut down .
How th e sys te m work s
The Anti-Lock Brake System (ABS) , E lectronic Differential Lock (EDU
and the Anti -Sl ip Regu lation System (ASR) are integrated in the e lec­
tronic stabi li z ation program. In addition to the data provided by
these functions, the ESP control unit requires additional measure­ ment data provided by high performance sensors . T he rotational
speed of the vehic le about its ver tica l axis, t he late ral acce leration
acting on the vehic le, the brake pressure and the steering ang le are
a ll measured .

The direction in which the driver wishes to travel is determined with
the aid of the steering angle and vehicle speed and is continua lly
compared with the actual behavior of the vehicle. If the two do not
match, -for example, when the vehicle starts hydrop laning on a
wet road -, ESP will automatical ly brake the appropriate wheel to
correct the problem.
The veh icle is then stabi lized by the forces act ing on the whee l
during braking. If the vehicle is oversteering (rear tends to skid out
of the turn), the brakes are mainly app lied on the whee l that is on
the outside of the curve. In the case of a vehicle that is understeering
(tendency to s lide out of the curve), the brakes are applied at the
rear wheel that is on the inside of the curve . An acoustic signal indi­
cates when ESP brake application cuts in =>
&.
The system operates across the entire speed range in combinat ion
with the ABS system => page 216 . If the Anti -Lock Brake System
(ABS) malfunctions, the ESP wi ll be out of act ion as well.
Activa tion
When you turn on the engine, ESP w ill automatica lly be activated
and will perform a self -test .
The system can be activated o r deactivated by pressing the butto n
=> page 212, fig . 190 . The warning light comes on when the system
is switched off .
Normally, the ESP should a lways be on, however, it may be advanta­
geous to turn off the system in certain specia l cases when some
degree o f wheel spin is desired such as :
• when driving with snow chains
• when driving in deep snow or on a loose surface (to allow the
whee ls to dig in to reach firm ground)
• when trying to "rock" the vehicle free whe n it has become stuck .
The system shou ld be reactivated once you are no longer in such
situations.
Both , the ABS and EDL systems are still functioning even if the ESP
is switched off .
Controls and equip­
ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
& WARNING
The Ele ctron ic Stab ilization Program is neve rth ele ss s ubje ct to th e
law s of phy sic s. It is p art icularly important to pay at tent ion to thi s
f ac t on wet and slipper y ro ad s. It i s therefore important th at yo u
alway s adapt your driving to the condition of the road and traffic
c onditio ns. Do not allo w the in crea sed safety prov ided by t he Ele c­
tronic Stabilization Program sy stem to lull you into a ccepting
addition al safety ri sk s.
• Plea se note that when ESP i s deactivated , the drive wheel s can
s pin on icy and slippery ro ads a nd the vehi cle can break away -
d anger of skidding ! C
E lectronic differential lock CEDL)
The electronic differential lock monitors the rotational
speed of the drive wheels.
Gener al notes
The electronic differential lock (EDU helps the car to start moving,
accelerate and c limb a gradien t on surfaces providing poor or
a lmost no grip . Without EDL, this would be difficult , if not impos ­
sible.
How the syst em works
The EDL operates automat ical ly . It monito rs the rotationa l speed of
the drive whee ls on an axle with the he lp of the ABS sensors
=> page 216 . If a noticeable difference in rotational speed between
the drive wheels on one axle is de tected (e.g. on slippery grou nd on
one side), the spinning wheel is braked, thereby transferring power
to the other drive wheel or wheels (a ll -whee l drive) . This is done up
to a speed of about 60 mph ( 100 km/h). Noises from the brake
system signal that wheel spin is being control led.
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Vehicle care Do-it-yourself service Technical data

& WARNING (c ont in u ed)
ext ra sa fe ty a fforded by the ABS tempt you into t ak in g ex tr a risks .
The ABS cannot overco me th e law s of ph ysics.
[ i J Tips
• If ABS is not funct ioning properly, a warning light will come on.
See
=> page 20.
• If a fau lt occurs in the ABS, the EDL is also not funct ion ing . This
is indicated by the ABS warning light.
Brake assistant
T he brake assistant is designed to achieve the optimum
braking effect.
The brake assistant helps to increase the effective braking power
and thus to achieve a shorter stopping distance . If the driver
presses the brake pedal very quick ly, the brake assistant automati ­
cally boosts the braking force to the maximum level, up to the point
where the anti -lock brake function (ABS) intervenes to stop the
wheels from locking. You should then keep the brake pedal pressed until the vehicle has braked to the required speed. The brake assis­
tant switches itself off as soon as you re lease the brake peda l.
The brake assistant will not be operative if there is a malfunction in
the ABS .
& WARNING
Please remembe r that the accident risk always in cre a se s if you
dri ve to o fa st, e spe cially in cor ner s o r on a slipp ery road , or if you
follow th e vehicle ahead of you too clos ely. An increased a ccident
ri sk ca nnot be comp en sa ted even b y the brake assista nt , s o
alwa ys maintain a safe spe ed . •
Controls and equip­ ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
Servotronic® -advanced power
steering system
The power steering systems uses the power of the
running engine to allow precise steering with little effort.
The advanced Servotronic ® power steering system senses the road
speed and electronically adjusts power assistance to provide
comfortab le and safe steering response exactly matched to the
vehicle speed.
Power steering will not work if the engine is off. As a result, the
steering whee l wil l be hard to turn .
The power steering fluid level is checked during the schedu led
maintenance services.
0 Note
If there is an electronic ma lfunction, servotronic will still function
like a conventional power steer ing system, providing a constant
steering support force that is no longer proportionate to the vehicle
speed. This is most noticeable when tu rning the steering whee l at
low speeds (for examp le when parking), -more effort wil l be
requi red than usual.
• Be aware of the different than usual steering response and
adjust you r steering force accordingly .
• Have the problem checked and set right by an Audi dealer as
soon as possible .
[ i J Tips
• When the engi ne is running, never hold the steering whee l
turned all the way to the right or to the left for longer than 15
seconds. The power steering pu mp will overheat the hydraulic fluid
if you keep holding the steering wheel turned a ll the way. This is
likely to damage the power stee ring system.
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Vehicle care Do-it-yourself service Technical data

___ ln_ te_ ll..,,ig ..,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
• If the power steering system should fail entirely, or if the engine
is not running (for example, while being towed), you will still be able
to steer the vehicle . However, considerably more effort will be
required to do so.
• If the power steering system should have a leak, or is not func­
tioning properly, contact your authorized Audi dealer immediately.
• The power steering system requires a specially formulated
hydraulic fluid. The power steering reservoir is the one located most
forward on the left side of the engine compartment=> page 251. The
correct fluid level in the reservoir is important for proper func­
tioning of the power steering. •
Driving with your quattro®
With All Wheel Drive, all four wheels are driven.
General information
With All Wheel Drive, power is distributed to all four wheels. This
happens automatically depending on your driving style and the
road conditions at the time. See also=> page 213, "Electronic differ­
ential lock (EDU".
Winter tires
When driving in the winter, your vehicle with All Wheel Drive has an
advantage, even with regular tires. In winter road conditions it may
be advisable to mount winter tires (or all-season tires) for improved
driveability and braking: these tires must be mounted on
all four
wheels.
See also => page 284, "Winter tires".
Snow chains
Where snow chains are mandatory on certain roads, this normally
also applies to vehicles with all -wheel drive => page 285, "Snow
chains".
Replacing wheels/tires
Vehicles with All Wheel Drive must always have tires of the same
size. Also avoid tires with different tread depths. For details see
page => page 279, "New tires and replacing tires and wheels".
Off-Road driving?
Your Audi does not have enough ground clearance to be used as an
off-road vehicle. It is therefore best to avoid rough tracks and
uneven terrain as much as possible. Also refer to=> page 221.
& WARNING
Always adjust your driving to road and traffic conditions. Do not
let the extra safety afforded by the all-wheel drive tempt you into
taking extra risks.
• Although the quattro®all-wheel drive is very effective, always
remember that braking capacity is limited 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 (hydro­ planing). If this should occur, you will have no warning from a
sudden increase in engine speed as with a front-wheel drive
vehicle. Always drive at speeds which are adjusted to the road conditions -risk of crash! •