2009 AUDI S4 CABRIOLET service

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

Airbag system -----------------=~-
& WARNING (continued)
• 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,
immediately install the rear -facing child safety seat in a rear
seating position and have the airbag system inspected 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 .
• Never put the forward-facing child restraint up against or very
near the instrument panel.
• 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 forward-facing child
restraint. The backrest 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. •
Advanced Airbag System components
The front passenger seat in your vehicle has a lot of very important
parts of the Advanced Airbag System in it. These parts include the
weight-sensing mat, sensors, wiring, brackets, and more. The func­
tion of the system in the front passenger seat is checked by the elec­
tronic control unit when the ignition is on. The control unit monitors
the Advanced Airbag System and turns the airbag indicator light on
when a malfunction in the system components is detected. The
function of the airbag indicator light is described in greater detail
Controls and equip­ ment Safety first Vehicle operation
below.
Because the front passenger seat contains important parts
of the Advanced Airbag System, you must take care to prevent it
from being damaged. Damage to the seat may prevent the
Advanced Airbag for the front passenger seat from doing its job in
a crash.
The front Advanced Airbag System consists of the
following:
• Crash sensors in the front of the vehicle that measure vehicle
acceleration/deceleration to provide information to the Advanced
Airbag System about the severity of the crash.
• An electronic control unit, with integrated crash sensors for front
and side impacts. The control unit "decides" whether to fire the
front airbags based on the information received from the crash sensors. The control unit also "decides" whether the safety belt
pretensioners should be activated.
• An Advanced Airbag with gas generator for the driver inside the
steering wheel hub.
• An Advanced Airbag with gas generator inside the instrument
panel for the front passenger .
• A weight-sensing mat under the upholstery padding of the front
passenger seat cushion that measures the total weight on the seat.
The information registered is sent continuously to the electronic
control unit to regulate deployment of the front Advanced Airbag on
the passenger side.
• An airbag monitoring system and indicator light in the instru ­
ment cluster ~
page 179.
• The PASSENGER AIR BAG OFF light comes on and stays on in the
center of the instrument panel~
page 180, fig. 174 and tells you
when the front Advanced Airbag on the passenger side has been
turned off .
• A sensor below the safety belt latch for the front seat passenger
to measure the tension on the safety belt. The tension on the safety
belt and the weight registered by the weight -sensing mat help the
control unit "decide" whether the front airbag for the front _,.
Vehicle care Do-it-yourself service Technical data

__________________________________________________ A_ i_ r _b _a...; g::- s_ y=--- s_t _e _m ___ __
& WARNING (continued )
airbag dur ing braking or in a sudden maneuver . Objects ne ar the
airbags can become proje ctiles and cau se injury , particularly when
the seat is reclined .
• Never tilt the front passenger seat backrest forward when the
vehicle is moving . An inflating airbag will force the backrest back­
ward and can injure rear seat occupants.
_& WARNING
The fine dust created when airbags deploy can cause breathing problems for people with a history of asthma or other breathing
conditions.
• To reduce the risk of breathing problems, those with asthma or
other respiratory conditions should get fresh air right away by
getting out of the vehicle or opening windows or doors.
• If you are in a collis ion in which airbags deploy, wash your
hands and face with mild soap and water before eating.
• Be careful not to get the dust into your eyes , or into any cuts or
scratches .
• If the residue should get into your eyes, flush them w ith
water. •
Monitoring the Advanced Airbag
System
Airbag monitoring indicator light :~
Two sep arate in dica tors m onitor the fu ncti on of th e
Adv anced A irba g Sys tem: the airbag moni tor ing in dica to r
l ight and t he
PASSENGER AIR BAG OFF light.
The Advanc ed A ir b ag S yst em (includ ing the e lec tronic co ntro l unit,
sensor c ircuits and system wiring) is monitored continuously to
Controls and equip­ ment Safety first Vehicle operation make sure that it is functioning properly whenever the ignition is on
.
Eac h tim e you tu rn on t he ignit io n, th e airbag monitoring ind ica tor
light
fl wi ll come on for a few seconds (self diagnostics) .
The system must be inspected when the indicator l ight ~:
• do es not com e on when the ig nit ion is sw itch ed on,
• does not go out a few seconds after you have switched on the
i gni tion , or
• comes on while driving.
I f an a irbag s ystem malfu ncti on is detec ted , the indi cator light will
first start flash ing to catch the driver's attention and then sta y on
co nti nuou sly to serve as a constant r eminder to h ave the sys tem
inspected immediately.
If a malf unctio n occurs that t urns the front airbag on the passenger
s id e off , the PASS ENGER AIR BAG OFF light w ill come on a nd s ta y on
whenever the ig nition is on.
_& WARNING
An airbag system that is not functioning properly cannot provide
s upplemental protect ion in a frontal crash .
• If the airbag indicator light comes on , it means that there may
be something wrong with the Advanced Airbag System . It is
possible that the airbag will inflate when it is not supposed to, or
will not inflate when it should .
• Have the airbag system inspected immediately by your Audi
dealer. •
Vehicle care Do-it-yourself service Technical data

__________________________________________________ A_ i_ r _b _a...; g::- s_ y=--- s_t _e _m ___ ffllll
the weight -sensing mat to measure more weight than is actually on
the seat .
If the PA SSENGER AIR BAG OFF light still d oes not come on and does
not stay on continuously (when the ignition is switched on),
• take the child restraint off the front passenger seat and insta ll it
properly at one of the rear seat positions. Have the airbag system
inspec ted by your Audi dea ler immediately .
• move the child to a rear seat position and make sure that the
child is proper ly restrained i n a child restraint that is appropriate for
its size and age.
The
PASSENGER AIR BAG OFF light shou ld NOT come on when the
ignition is on and an adult is sitting in a proper seating position on
the front passenger seat . If the
PASSENGER AIR BAG OF F light
comes on and stays on or flashes for about 5 seconds whi le driving,
under these circumstances, make sure that:
• the adult on the front passenger seat is properly seated on the
center of the seat cushion with his or her back up against the back­
rest and the back rest is not reclined => page 148, "Pro per occupant
seating positions",
• the adult is not taking weight off the sea t by ho lding o n to the
passenger assist handle above the front passenger door or
suppo rting thei r weight on the armrest,
• the safety belt is being proper ly worn and that there is not a lot
of slack in the safety bel t webbing,
• accessory seat covers or cushions or other things that may cause
an incorrect reading or impression on the weight -sensing mat
under the upho lstery of the seat have been removed from the front
passenger seat,
• a safety belt extender has not been left in the safety be lt latch for
t he front passenger seat .
In addition to the
PASSENGER AIR BAG OFF l ight in the center of the
instr ument panel, the message
PASSENGER AIR BAG OFF or
PAS SENGER AIR BAG ON wi ll briefly appear in the instrument c luster
Controls and equip­ ment Safety first
Vehicle operation display. This is to inform the driver of the current front passenger
a
ir b ag status .•
Important safety instructions on monitoring
the Advanced Airbag System
& WARNING
An airbag system that is not fun ctioning properly cannot provide
supplemental protection in a frontal cra sh .
• If the airbag ind icator li ght come s on , it means that there may
be something wrong with the Advan ced Airbag System . It is
possible that the airbag will inflate when it is not suppo sed to , or
will not inflate when it should .
• Ha ve the airb ag system inspected immedi ately by your Audi
dealer.
& WARNING
If the front airbag inflate s, a child witho ut a child restraint , in a
rearward-facing child safety seat or i n a forward -fa cing child
restr aint that has not been properly installed will be seriously
injured and can be killed .
• Even though your vehicle is equipped with an Advanced Airbag
Sy stem , make certain that all children , e speci ally 12 year s and
younger , always ride on the back seat p roperly re strained for their
age and size .
• Always install forward or rear -facing child safety seat s on the
re ar s eat - even with an Ad van ced Airb ag Sy stem .
• If you mu st install a rearward -fa cing child safety seat on the
front pa ssenger seat be cau se of ex ceptional cir cum stance s and
the PASSENGER AIR BAG OFF light does not appear and stay on ,
immediately in stall the rear -facing child safety seat in a rear ...
Vehicle care Do-it-yourself service Technical data

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& WARNING (continued )
• Always make sure that the side airbag can inflate without inter­
ference :
- Never install seat covers or replacement upholstery over the
front seatbacks 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 original seat covers or to the seam in the area
of the side airbag module must always be repaired immedi ­
ately by an authorized Audi dealer.
• The airbag system can be activated only once. After an airbag
has inflated, it must be replaced by an authorized Audi dealer or
qualified technician who has the technical information , training
and special equipment nece ssary.
• The airbag system can be deployed only once . After an airbag
has been deployed , it must be replaced with new replacement
part s designed and approved especially for your Audi model
version. Replacement of complete a irbag systems or airbag
components must be performed by qualified workshops only .
Make sure that any airbag service action is entered in your Audi
Warranty
& Maintenance booklet under AIRBAG REPLACEMENT
RECORD .
• In accidents when an airbag is deployed , the vehicle battery
s eparates the alternator and the starter from the vehicle electrical
system for safety reasons with a pyrotechnic circuit interrupter.
-Work on the pyrotechnic circuit interrupter must only be
performed by a qualified dealer -risk of an accident !
- If the vehi cle or the circuit interrupter is scrapped , all appli ­
cable safety precautions must be followed . •
Controls and equip­ ment Safety first
Vehicle operation
Other things that can affect Advanced Airbag
performance
Changing the vehicle 's suspension system can cha nge the way that
the Advanc ed Ai rbag Syste m perfor ms in a cras h. Fo r ex amp le,
u sing tire -rim combinations not a pproved by Audi, lowering the
ve hicle , c hang ing the st iffness o f the suspe nsion, inclu din g the
spr ings, s uspension struts, shock absorbers etc. can change the
fo rc es that ar e meas ured by th e a irbag sens ors and sent to the e lec ­
tronic control un it. Some suspens ion changes can, for example,
in crea se th e fo rc e leve ls meas ured by th e se nsors and ma ke t he
airbag system dep loy in crash es in wh ich it wou ld not dep loy if the
c h anges had no t been m ade . Ot her k in ds of cha nge s m ay red uce
the fo rce levels measured by the sensors and p revent t he airba g
fr om depl oyin g whe n it should.
T he sensors in the safe ty b elt b uckle fo r the driver a nd front
passenger seat te ll the electronic control module if the safety belt is
l a tc h e d or not. If the s afe ty be lt is bei ng use d, t he fr ont ai rbag w ill
dep loy at a s lightly higher rate of vehic le dece leration than if the
sa fe ty belt is not be ing used . T here for e, in a partic ular co lli sion , it is
possible t hat an airbag will not dep loy at a seating position w here
the safe ty belt is b ein g us ed b ut will infl ate a t th e po siti on w here the
safety belt is not being used. It is important that nothi ng interfere
with the safety belt b uck les so that the sensors can send the correct
i nformat ion about safety b elt use to the electronic control un it.
& WARNING
Changing the vehicle's suspension including use of unapproved
tire -rim combinations can change Advanced Airbag performance
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-r im combinations that have not been approved
by Audi. .,.
Vehicle care Do-it-yourself service Technical data

___ 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
~

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& WARNING (continued)
-Always sit in an upright position and never lean against the
area where the supplemental side airbag is located.
- Never let a child or anyone else rest their head against the
side trim panel in the area where the supplemental side airbag
inflates.
- Always make sure that safety belts are worn correctly,
- Do not let anyone sitting in the front seat put their hand or
any other parts of their body out of the window .
• Always make sure that the side airbag can inflate without inter ­
ference .
- Never install seat covers or replacement 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 deploy.
- Damage to the original seat covers or to the seam in the area
of the side airbag module must always be repaired immedi­
ately by an authorized Audi dealer .
• Objects between you and the airbag can increase the risk of
injury in an accident by interfering with the way the airbag unfolds
or by being pushed into you as the airbag inflates .
- Never place or attach accessories or other objects (such as
cup holders, telephone brackets, or even large, bulky objects)
on the doors, over or near the area marked "AIRBAG" on the
seat backrests .
- Such objects and accessories can become dangerous projec­
tiles and cause injury when the supplemental side airbag
deploys.
- Never carry any objects or pets in the deployment space
between them and the airbags or allow children or other
passengers to travel in this position .
Controls and equip­ ment Safety first
Vehicle operation
& WARNING (continued)
• Always prevent the side airbags from being damaged by heavy
objects knocking against or hitting the sides of the seatbacks.
• The airbag system can only be triggered once. If the airbag has
been triggered, the system must be replaced by an authorized
Audi dealership.
• Damage (cracks, deep scratches etc.I to the original seat covers
or to the seam in the area of the side airbag module must always
be repaired immediately by an authorized Audi dealer .
• If children are seated improperly, their risk of injury increases
in the case of an accident~
page 190, "Child Safety".
• Never attempt to modify any components of the airbag system
in any way .
• In a side collision, side airbags will not function properly if
sensors cannot correctly measure increasing air pressure inside
the doors when air escapes through larger, unclosed openings in
the door panel.
- Never drive with interior door trim panels removed.
-Never drive when parts have been removed from the inside
door panel and the openings they leave have not been properly
closed.
- Never drive when loudspeakers in the doors have been
removed unless the speaker holes have been properly closed.
- Always make certain that openings are covered or filled if
additional speakers or other equipment is installed in the
inside door panels .
- Always have work on the doors done by an authorized Audi
dealer or qualified workshop . •
Vehicle care Do-it-yourself service Technical data

--------------------------------------------~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