2008 AUDI A4 AVANT service

Airbag system 111111
-------------------------------------------- -=-:~--___.
• A sensor below the safety belt latch for the front seat passenger
t o m easure the tens io n on t he sa fety be lt. T he tension on the safe ty
belt and the weight registered by the weight -sensing mat help the
contr ol unit "decide" whe the r the front ai rbag for the fron t
passenger seat should be turned off or
not=> page 189, "Child
r est ra ints on the front seat - some important th ings to know".
• A sensor in the safety belt latch for the driver and for the front
seat passenge r that senses whether t hat safety bel t is la tched or no t
and transmits this information to the e lectronic control unit.
& WARNING
Damage to the front pas senger seat can pre vent the front airbag
from working properly.
• Improper repair or disassembly of the front passenger and
driver seat will prevent the Advanced Airbag System from func ­
tioning properly .
• Repairs to the front passenger seat must be performed by qual ­
ified and properly trained workshop personnel .
• Never remove the front pa ssenger or driver seat from the
vehi cle .
• Ne ver remo ve the upholstery from the front passenger seat .
• Never disassemble or remove parts from the seat or disconnect
wires from it .
• Never carry sharp objects in your pockets or place them on the
seat . If the weight -sen sing mat in the passenger seat i s pun ctured
it cannot work properly.
• Never carry things on your lap or carry objects on the
passenger seat . Such items can increase the weight registered by
the weight -sensing mat and send the wrong informat ion to the
airbag control unit .
• Never store items under the front passenger seat . Parts of the
Advanced Airbag System under the passenger seat could be
d amaged , preventing them and the airbag system from working
properly.
Controls and equip­ ment Safety first
Vehicle operation
& WARNING (continued )
• Never place seat covers or replacement upholstery that have
not been specifically appro ved by Audi on the front seat s.
• Seat covers can prevent the Advanced Airbag System from
recognizing child restraint s or occupants on the front passenger
seat and prevent the side airbag in the seat backrest from
deploying properly.
• Never use cushions, pillows , blankets or similar items on the
front passenger seat. The additional padd ing will prevent the
weight-sensing mat in the seat from accurately registering the
child restraint or person on the seat and prevent the Ad vanced
Airbag System from functioning properly .
• If you mu st use a child re straint on the front pas senger seat
and the child restraint manufacturer's instru ctions require the use
of a towel , foam cu shion or something el se to properly position
the child restraint , make certain that the PASSENGER AIR BAG OFF
light comes on and stays on whenever the child restraint i s
installed on the front passenger seat.
• If the PASSENG ER AIR BAG OFF light does not come on and stay
on , immed iately install child re straint in a re ar seat ing position
and have the airbag sy stem inspected by your Audi dealer . •
How the Advanced Airbag System
components work together
The front Advanced Airbag System and the side airbags supplement
the prote ction off ered by the fro nt three -p oi nt safe ty belts with
pretensioners and load limiters and the adjustable head restra ints
to help reduce the risk of injury in a wide range of accident and
crash situations. Be sure to read the important informat ion about
safety and heed the WARNI NGS in this chapter.
Dep loyment of the Adva nced Ai rbag Sys tem a nd th e activation of
the safety belt pretensioners depends on the dece leration
measu red by the crash senso rs and registered by the electro nic _.,
Vehicle care Do-it-yourself service Technical data

Airbag system 111111
-----------------------------=--=-------
It is important to remember that while the supplemental airbag
system is designed to reduce the likelihood of serious injuries, other
injuries, for example swelling, bruising and minor abrasions, can
also happen when airbags inflate. Airbags do not protect the arms
or the lower parts of the body. Front airbags only supplement the
three point safety belts in some frontal collisions in which the
vehicle deceleration is high enough to deploy the airbags.
Front airbags
will not deploy:
• if the ignition is switched off when a crash occurs,
• in side collisions,
• in rear -end collisions,
• in rollovers ,
• when the crash deceleration measured by the airbag system is
less than the minimum threshold needed for airbag deployment as
registered by the electronic control unit.
The front passenger airbag
will also not deploy:
• when the front passenger seat is not occupied,
• when the weight on the front passenger seat as sensed by the
Advanced Airbag System indicates that the front airbag on the
passenger side has to be turned off by the electronic control unit
(the PASSENGER AIR BAG OFF light comes on and stays onl.
& WARNING
Sitting in the wrong position 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 their body too close to the area
where the airbags are located.
• Occupants who are unbelted, out of position 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 189.
Controls and equip­ ment Safety first
Vehicle operation
& 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 seat.
• 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
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 objects) 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 _,,
Vehicle care Do-it-yourself service Technical data

__________________________________________________ A_ i_ r _b _a-' g=- s_ y=-- s_t _e _m ______ lfflll
PASSENGER AIR BAG OFF light
N
-M -J., a, cc
Fi g. 18 0 Sec tion fr om
t h e i nstr um ent pa nel:
P ASSE NG ER AI R BA G
OFF lig ht
The PASSENGER AIR BAG OFF light is located in the center o f the
ins trumen t panel
=> fig . 180 .
The PASSENGER AIR BAG OFF light wil l come on and stay on to te ll
you when the front Advanced Airbag on the passenger side has been turned off by the electronic control unit. Each time you turn on
the ign it ion, the
PA SS ENGER AIR BA G OFF light wi ll fl as h for a few
seconds and :
• will stay on if t he front passenger seat is not occupied,
• will stay on if there is a small child or chi ld restraint on the front
passenger seat,
• will go out if the front passenger seat is occupied by an adult as
registered by the we ight -sens ing mat.
The
PA SS ENGER AIR B AG OFF light mu st come on and stay on if the
ignition is on and
• a car bed has been instal led on the front seat, or
• a rearward -facing chi ld restraint has been installed on the front
passengerseat,or
Controls and equip­ ment Safety first
Vehicle operation
• a forward -facing child restraint has been instal led on the front
passenger seat, or
• the weight register ed on the front passenger seat is equa l to or
less than the combined weigh t of a typica l 1 year-old restrained in
one of the rear -facing or forward -facing infant restraints listed in
Federa l Motor Veh ic le Safe ty S tandard
208 with wh ich the Advanced
Airbag System in your vehicle was certified .
If the front passenger seat is not occupied, the front airbag will not
dep loy, and the
PA SS ENGER AIR BAG OFF light will stay on . Never
insta ll a rearward -facing child restraint on the front passenger seat,
the safest place for a child in any kind of ch ild restraint is at one of
the seating positions on the rear
seat => page 189, "Ch ild restraints
on the front sea t-some important things to know"
and => page 210,
"Chi ld Safety" .
If the PASSENGER AIR BAG OFF light comes on when one of the
condit ions listed above is met , be sure to check the light regu lar ly
to make certain that the
PA SSENGER AIR BAG OFF light stays on
cont inuously whenever the ignition is on . If the PASSENGER AIR
BAG OFF light does not appear and not stay on all the time , stop as
soon as it is safe to do so and
• reactivate the system by turning the ignition off and then turning
it on again;
• remove and reinstall the ch ild restraint. Make sure that the child
res tra int is proper ly instal led and t hat t he sa fety be lt for the front
passenger seat has been correctly routed around the child restraint
as described in the chi ld restraint manufacturer's instructions;
• make sure that the convertible locking feature on the safety belt
for the front passenger seat has been activated a nd that the safety
belt has been pulled t ight . The belt must not be loose or have loops
of slack so t hat t he sensor below t he safety belt latch on the seat can
do its job
=> page 220.
• make s ure that th ings that may inc rease the we ight of the child
and child safety seat are not being transported on the front
passenger seat;
Vehicle care Do-it-yourself service Technical data

& 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 appear and stay on ,
immediately install the rear -facing child safety seat in a rear
seating posit ion and have the airbag system inspected by your
Audi dealer .
• A tight tether or other strap on a rearward-facing child restraint
attached to the front passenger seat can put too much pressure
on the weight-sensing mat in the seat and register more weight
than is 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 suppressed causing
serious or even fatal injury to the child.
• If , in exceptional circumstances , you must install a forward ­
facing child restraint on the front passenger seat , always move the
seat into its rearmost position in the seat 's fore and aft adjust­
ment range , as far away from the airbag as possible. 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 .
& 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 is properly seated and
restrained at one of the rear seating positions .
• Have the airbag system inspected by your Audi dealer before
transporting anyone on the front passenger seat .
Controls and equip­ ment Safety first
Vehicle operation
Airbag system
[ i ] Tips
If the w eig ht-sens ing ma t in th e front passe nger seat detects an
e m pty seat , the front airbag on the pa ssenge r side wil l be turned
o ff , a nd PASSENGER AIR BAG OFF will stay o n.
a
Repair, care and disposal of the airbags
Pa rts o f the airba g sy ste m are i nsta lled at many d ifferen t pl aces on
y our Audi. Instal ling, removing , se rvicing or re pairing a pa rt in an
ar ea of th e ve hicle ca n da mage a part of an airbag syst em and
prevent that system from wor king properly in a co llision.
T he re a re so me impo rtant thin gs you have to know t o make sure
that the effectiv eness of the system will not be impaired and that
di scar ded co mpon ents do not ca use inju ry o r po llut e th e env iron­
m ent .
& WARNING
Improper care , servicing and repair pro cedures 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 such as cup holders or telephone
mountings to the surfaces 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 cleaners
could damage the airbag cover or change the stiffness or strength
of the material so that the airbag cannot deploy and protect prop ­
erly .
• Never repair , adjust , or change any parts of the airbag system.
• All work on the steering wheel, instrument panel, front seats or
electrical system (including the installation of audio equipment ,
...,
Vehicle care Do-it-yourself service Technical data

-Airbag system ---=--.:..,.._ _________________________________ _
&, WARNING (continued )
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 workshop .
• Never modify the front bumper or parts of the vehicle body .
• Always make sure that the side airbag can inflate without inter ­
ference :
- Never install seat covers or replacement upholstery over the
front seatba cks 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 necessary.
• The airbag system can be deployed only once. After an airbag
has been deployed, it must be replaced with new replacement
parts designed and approved especially for your Audi model
version. Replacement of complete airbag systems or airbag
components must be performed by qualified workshops only .
Make sure that any a irbag service action is entered in your Audi
Maintenance
& Warranty booklet under AIRBAG REPLACEMENT
RECORD .
• In accidents when an airbag is deployed, the vehicle battery
separates the alternator and the starter from the vehi cle electrical
system for safety reasons with a pyrotechnic circuit interrupter.
-Work on the pyrotechni c circuit interrupter must only be
performed by a qualified dealer -risk of an accident !
&, WARNING (continued )
-If the vehicle or the circuit interrupter is scrapped, all appli­
cable safety precautions must be followed.
•
Other things that can affect Advanced Airbag performance
Changing the vehic le 's suspension system can change the way that
t he A dvance d Ai rbag S ystem p erf o rm s in a c rash. F or example,
using tire -rim combinations not approved by Audi, lowerin g the
ve hicle , ch ang ing the stiff ness of the suspe nsion, includ ing the
springs, suspension struts, shock absorbers etc. can chang e the
fo rces that a re measured by the airbag senso rs and se nt to the elec­
tronic control u nit. Some suspension chan ges can, for exampl e,
i n crease the fo rce level s measured by the sen so rs and ma ke the
a irbag s yste m de plo y in cras he s in w hi ch it wou ld not de ploy if th e
changes had not been made. Other kinds of changes may reduce
t h e fo rce lev els measu red by the senso rs a nd p reven t the airb ag
from dep loying when it should.
T he sens ors i n the safe ty belt buckle f or the dri ve r and front
passeng er seat tell t he electronic contro l modu le if the safety belt is
la tched o r not. If t he sa fe ty bel t i s being used, the fro nt ai rbag wi ll
deploy at a s ligh tly high er rate o f veh icle dece lerat io n th an if th e
safety be lt is not being u sed . Th erefo re , in a particula r co llision, it is
poss ib le th at a n airbag will not deplo y at a seat ing po sit io n wh ere
the safety be lt is being used but wi ll inflate at the pos ition where the
safety be lt is not bei ng used . It is im po rta nt tha t noth ing i nte rfere
with the safety belt buc kles so that the sensors can send the correct
i nf orm atio n abou t s afe ty belt use to th e electr onic co ntrol uni t.
~

__________________________________________________ A_ i_ r _b _a-' g=- s_ y=-- s_t _e _m ______ lJfflll
& WARNING (continued)
expansion range of a SIDEGUARD head airbag can dangerously
interfere with its function. A deploying head airbag develops
enough force to catapult any piece of add-on component out of its
path of inflation and into the passenger compartment. An occu­
pant hit by such a projectile can suffer serious injury or death
=> page 349, "Technical Modifications".
• Do not swivel the sun visors to the side if you have any objects
clipped onto them (for example
pens!. If the airbag should deploy,
you could be injured by these objects.
• Use the built-in coat hooks only for lightweight clothing. Never
leave any heavy or sharp-edged objects in the pockets that may
interfere with airbag deployment and can cause personal injury in
an accident.
• Never use hangers to hang clothing from the hooks.
• Only use factory-installed sun shades or, in the case of shades
installed after the vehicle leaves the factory, only Audi roll-up
sunscreens may be used => page 348, "Additional accessories and
parts replacement".
• Always sit in proper seating position and wear safety belts
while traveling so that the side curtain airbags can help provide protection .
• The airbag system can only be triggered once. If the airbag has
been triggered, the system must be replaced by an authorized
Audi dealer or qualified workshop.
• Always have work involving the side curtain airbag system,
removal and installation of the airbag components, or other
repairs performed by a qualified dealership. Otherwise the airbag
system may not work correctly.
• Never attempt to modify any components of the airbag system
in any way. •
Controls and equip­ ment Safety first
Vehicle operation Vehicle care Do-it-yourself service Technical data

& WARNING (conti nued )
• Alw ays install r ear-facing child saf ety s eats on the r ear seat.
• If you mu st in sta ll a re arwa rd f acing child safe ty s eat on the
front pas senger seat in exc eptional cir cum stances and the
PASSENGER AIR BAG OFF light doe s not come on and stay on,
immediat ely install th e rear-fa cing child safety s eat in a rear
s e ating po sit ion and h ave the airb ag sys tem in spe cted immedi ­
a tel y by y our Audi dealer .
& WARNING
If, in exceptional circum stance s, you must in stall a forward -fac ing
c hild re st ra int on the fr ont p assenge r's s eat:
• Alway s make sure the forward -facing seat ha s been de signed
and cert ified by it s m anuf acturer for u se on a front se at with a
pa ssenger front and side airbag .
• Always follow the m anufacturer's instruct ions provided w ith
the child safet y seat or c arrier.
• Alway s m ov e th e passeng er sea t into it s re arm ost p osit ion in
the seat' s fore and aft adju stment range , as far away from the
a irb ag as possible before installin g the ch ild r estr aint . The b ack­
rest must be adjusted to an upright po sition.
• Alway s ma ke sure th at the PASSENGER AIR BAG OFF light
come s on and stay s on all the time wheneve r the ignition i s
s wit ched on . •
Advanced front airbag system and children
Your vehicle is equipped with a dual -stage front "Advanced Airbag
System" in comp liance with United States Federal Motor Vehicle
Safety Standard ( FMVSS) 208 as applicab le at the time your vehic le
was manufactured .
Controls and equip­
ment Safety first Vehicle operation
Chi
ld Sa fe ty
The Advanced Airbag system in your vehic le has been certified to
meet the " low -risk" require ments for 3 and 6 yea r- old c hild 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 inju ry 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 it ion, the system has been cert ified to comply with
the "suppression" requirements of the Safety Standard, to turn off
the front airbag for in fants up to 12 months who are restrained on
the front passeng er 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, sho uld
a lways ride in the back seat proper ly restra ined for the ir age and
size . The airbag 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 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 larger chi ld in a rearward ­
facing seat. •
Advanced Airbags and the weight-sensing
mat in the front seat
The Advanced A irbag System in your ve hicle detects the p resence
of an infant or chi ld in a child 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 meas ures total we ig ht of the ch ild and the
child safety seat and a chi ld blanket on the front passenger seat. The
weight o n the fr ont passenge r seat is related to the desig n 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 chi ld
_..
Vehicle care Do-it-yourself service Technical data

Child Safety -
---------------''------'
C. Forward-facing convertible child restraint systems,
manufactured on or after September 1, 2004:
• Britax Roundabo ut 161
• Brit ax Expressway
• Century Encor e 4612
• Century STE 1000 4416
• Cosco Olympian 02803
• Cosco Touriva 02519
• Evenflo Horizon V 425
• Evenflo M edallion 254
• Safety First Comfor t Ride 22-400
& WARNING
To reduce the risk of serious injury, make sure that the PASSENGER
AIR BAG OFF light comes on and stays on whenever a child restraint is installed on the front passenger seat and the ignition
is switched on.
• Take the child restraint off the front passenger seat and install
it properly at one of the rear seat positions if the PASSENGER AIR
BAG OFF light does not stay on.
• Have the airbag system inspected by your authorized Audi
dealer immediately.
[ i] Tips
Th e child s eats lis ted in cat egori es A to C have been tes ted by Audi
only for the Advanced Airbag function. •
Controls and equip­
ment Safety first Vehicle operation
Important safety instructions for using child
safety seats
Correct use of child safety seats substantially reduces the
risk of injury in an accident!
As the driver, you are responsible for the safety of every ­
body in the vehicle, especially children:
- Always use the right child safety seat for each child and
always use it properly :::>
page 215.
-Always carefully follow the child safety seat manufac­
turer's instructions on how to route the safety belt prop­
erly through the child safety seat.
- When using the vehicle safety belt to install a child safety
seat , you must first activate the convertible locking
retractor on the safety belt to prevent the child safety
seat from
moving => page 220.
- Push the child safety seat down with your full weight to
get the safety belt really tight so that the seat cannot
move forward or sideways more than one inch (2.5 cm).
- If a strap or tether is being used to tie the child safety
seat to the front passenger seat, make sure that it is not
so tight that it causes the weight-sensing mat to
measure more weight than is actually on the seat.
Always remember: Even though your vehicle is equipped with an
Advanced Airbag system, all children, especially those 12 years and
younger, should always ride in the back seat properly restrained for
their age and size .
..,_
Vehicle care Do-it-yourself service Technical data