ESP AUDI A4 AVANT 2008 Repair Manual

Child Safety -
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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

___ C_h_ i_ld _ S_ a_ f_ e_ t--= y'-------------------------------------------------
& WARNING
Not using a child safety seat, using the wrong child safety seat or
improperly installing a child restraint increases the risk of serious
personal injury and death .
• All vehicle occupants and especially children must always be
restrained properly whenever riding in a vehicle .
- An unrestrained or improperly restrained child can be injured or killed by being thrown against the inside of the vehicle or by
being ejected from it during a sudden maneuver or impact.
- An unrestrained or improperly restrained child is at much
greater risk of injury or death by being struck by an inflating
airbag.
• Commercially available child safety seats are required to
comply with U.S. Federal Motor Vehicle Safety Standard (FMVSSI
213 (in Canada CMVSS 2131.
-When buying a child restraint, select one that fits your child
and the vehicle.
- Only use child restraint systems that fully contact the flat
portion of the seat cushion. The child restraint must not tip or
lean to either side . Audi does not recommend using child safety
seats that rest on legs or tube-like frames. They do not provide
adequate contact with the seat .
- Always heed all legal requirements pertaining to the installa ­
tion and use of child safety seats and carefully follow the
instructions provided by the manufacturer of the seat you are
using.
• Never allow children under 57 inches (1.5 meters) to wear a
normal safety belt. They must always be restrained by a proper
child restraint system. Otherwise, they could sustain injuries to
the abdomen and neck areas during sudden braking maneuvers or
accidents.
• Never let more than one child occupy a child safety seat .
& WARNING (continued)
• Never let babies or older children ride in a vehicle while sitting
on the lap of another passenger .
- Holding a child in your arms is never a substitute for a child
restraint system .
- The strongest person could not hold the child with the forces
that exist in an accident. The child will strike the interior of the
vehicle and can also be struck by the passenger.
- The child and the passenger can also injure each another in
an accident.
• Never install rear-facing child safety seats or infant carriers on
the front passenger seat. A child will be seriously injured and can be killed when the passenger 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 or infant carriers on
the rear seat .
• Forward-facing child safety seats installed on the front
passenger's seat can interfere with the airbag when it inflates and
cause serious injury to the child. Always install forward-facing
child safety seats on the rear seat.
• If exceptional circumstances require the use of a forward­
facing child restraint on the front passenger's
seat, the child's
safety and well -being require that the following special precau ­
tions be taken :
- Make sure the forward-facing seat has been designed and certified by its manufacturer for use on a front seat with a
passenger front and side airbag.
- Always carefully follow the manufacturer's instructions
provided with the child safety seat or carrier.

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Booster seats
Properly used booster seats can help protect children
weighing between about 40 lbs. and 80 lbs. (18 kg and 36
kg) who are less than 4
ft. 9 in. tall.
Fig. 187 Rear seat:
child properly
restrained in a booster
seat
The vehicle's safety belts alone will not fit most children
until they are at least 4 ft. 9 in. tall and weigh about 80 lbs.
(36 kgl. Booster seats raise these children up so that the
safety belt will pass properly over the stronger parts of their
bodies and the safety belt can help protect them in a crash.
-Do not use the convertible locking retractor when using
the vehicle's safety belt to restrain a child on a booster seat.
-Always position the shoulder portion of the safety belt midway over the child's shoulder.
-Always make sure that the shoulder portion of the safety
belt never rests against or across the child's neck.
-Always make sure that the child can properly wear the
lap portion of the belt low across the thighs or pelvis and
never over the stomach or abdomen.
Children up to about 40 lbs (18 kg) are best protected in child safety
seats designed for their age and weight. Experts say that the skel­
etal structure, particularly the pelvis, of these children is not fully
developed, and they should not use the vehicle safety belts
~ page218,fig.187.
Children who weigh more than 40 lbs. (18 kg) may generally use the
available three point combination lap and shoulder belts when they
sit on an appropriate booster seat. Be sure the booster seat meets
all applicable safety standards.
Booster seats raise the seating position of the child and reposition
both the lap and shoulder parts of the safety belt so that they pass
across the child's body in the right places. The routing of the belt
over the child's body is very important for the child's protection .
This applies whenever a child uses the vehicle's safety belts, even
when the child is big enough to use them without a booster seat. Children age 12 and under should always ride in the rear seat .
Children should not ride in the front seat unless no other seating
position is available because crash statistics show that children are
better protected in the rear seat.
In a crash , airbags must inflate within a blink of an eye and with
considerable force . In order to do its job, the airbag needs room to
inflate so that it will be there to protect the occupant as the occu­
pant moves forward into the airbag.
A vehicle occupant including a child who is out of position and too
close to the airbag gets in the way of an inflating airbag. When an
occupant is too close, he or she will be struck violently and will
receive serious or possibly even fatal injury .
In order for the airbag to offer protection, it is important that all
vehicle occupants, especially any children, who must be in the front
seat in exceptional circumstances, be properly restrained and as far
away from the airbag as possible. By keeping room between the _.,.

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Children who weigh more than about 80 lbs (36 kg) and are at least
4 ft . 9 in. tal l can genera lly use the veh ic le's three po int lap a nd
shou lder belts . Chi ldren should use a lap belt only in very excep ­
tiona l situations and on ly if no child restraint system for the child's
size and weight or safer a lternative means of transportation of the
child is available. In these exceptiona l situations, the use of a lap
belt is better t han permitting t he ch ild to re main total ly unre ­
strained. But remember : a lap be lt cannot provide the same level of
protection as a proper c hild restraint or a t hree -poi nt lap and
shou lder be lt if the child is big enough . A lso, using a lap belt for
younger chi ldre n, who s hould be us ing a chi ld restrai nt, may v iola te
l aws in your state or Province .
N ever use a lap belt alone to rest ra in a chi ld that we ig hs less than
about 80 lbs (36 kg) and w ho is less t han 4'9" ta ll. A lways remember
t hat chi ld ren do not have the pronounced pelv ic structure requ ired
f or t he proper function o f lap belts . If a lap belt is o nly restra int
system available, then the chi ld's safety absolutely requires that the
l ap be lt be fastened snug ly and as low as possible around t he pelv is
l et a lap belt pass over the chi ld's stomach or abdomen .
& WARNING
Using wrong child restraints or improperly installed child
restraints can cau se seriou s personal injury or death in a crash.
• Failure to properly route safety belt s over a child's body will
cau se severe injurie s in a crash . The lap belt portion of the three
point belt a s well as any lap belt alone must always pass as low as
po ssible acros s the pelvis, never over the stomach or abdomen.
• An improperly worn safety belt will not provide the best protec­
tion in a crash and may cause serious personal injury . Al ways
make sure that children and other vehicle occupants properly
wear available restraint sy stem s. Carefully follow the in struction s
prov ided by the manufacturers of child restraints .
•
Installing a child safety seat
Securing a child safety seat using a safety
belt
S afe ty belts for the rea r seats and the fr ont pa ssenger can
be locke d with the c onvertible locking retract or to prop ­
erly secure child safety seats.
T he safe ty belts emergency locking re tracto rs fo r the rea r sea ts
sa fety be lts a nd for t he front passenger's seat safety belt have a
conve rtible lock ing ret ractor for child rest ra ints . The safety belt
must be loc ked so t hat belt webbing ca nnot unree l. The retractor
can be activated to lock the safety be lt and prevent the safety be lt
webbi ng from l oosen ing up dur ing normal dr ivi ng. A c hild sa fe ty
seat can only be properly instal led when the safety belt is locked so
t hat t he ch ild and c hild safety seat will s tay in place .
A lways remember: Even though your vehicle is equipped with an
Advanced Ai rbag sys tem, al l c h ild ren, especially those 12 years and
younger, should always r ide in the back seat proper ly restra ined for
their age and size.
& WARNING
Improperly installed child safety seats increase the risk of serious
per sonal injury and death in a collision .
• Always make sure that the safety belt retractor is locked when
installing a child safety seat. An unlo cked safety belt retra ctor
cannot hold the child safety seat in pla ce during normal driving or
in a crash.
• Alway s buckle the child safety seat firmly
in place even if a
c hild is not sitting in it. A loose child safety seat can fly around
during a sudden stop or in a collision
• Alway s make sure that the rear seat backre st to which the
center rear safety belt is attached is securely latched whenever
the rear center safety belt is being u sed to se cure a child re straint.
_,.

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& WARNING
Rearward-facing child restraints:
• 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 be especially careful if you must install a rearward
facing child safety seat on the front passenger seat in exceptional
circumstances.
• A tight tether strap on a rearward-facing child restraint
attached to the front passenger seat can put too much pressure
on the weight-mat in the seat and register a heavier weight in the
Advanced Airbag System. 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.
• Make sure that the PASSENGER AIR BAG OFF light comes on
and stays on all the time whenever the ignition is switched on.
• If 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. •
Activating the convertible locking retractor
Use the convertible locking retractor to secure a child
restraint.
Always heed the child safety seat manufacturer's instruc­
tions when installing a child restraint in your vehicle. To
activate the convertible locking retractor:
-Place the child restraint on a seat, preferably on the rear
seat.
-Slowly pull the belt all the way out.
-Route it around or through the child restraint belt path
=>& .
-Push the child safety seat down with your full weight to
get the safety belt really tight.
-Insert the belt tongue into the buckle for that seating
position.
-Guide the safety belt back into the retractor until the belt
lies flat and snug on the child safety seat.
-You should hear a "clicking" noise as the belt winds back
into the inertia reel. Test the convertible locking retractor
by pulling on the belt. You should no longer be able to
pull the belt out of the retractor. The convertible locking
retractor is now activated.
-Make sure that the red release button is facing away from
the child restraint so that it can be unbuckled quickly.
-Pull on the belt to make sure the safety belt is properly
tight and fastened so that the seat cannot move forward
or sideways more than one inch (2.5 cm).
& WARNING
Using the wrong child restraint or an improperly installed child
restraint can cause serious personal injury or death in a crash.
• Always make sure that the safety belt retractor is locked when
installing a child safety seat. An unlocked safety belt retractor
cannot hold the child safety seat in place during normal driving or
in a crash.
~

Child Safety -
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lower anchorages and help protect the seat material from
possible damage when installing child restraints that have
rigid lower anchorages and not straps with hooks.
Installing the guidance fixtures
- Push down on the seat cushion so that the lower anchor ­
ages are visible.
- Hold the guidance fixture with the part number facing downward and push it in the direction of the arrow onto
the
anchorage => fig. 193.
- Make sure that each of the two guidance fixtures per seat snaps into place.
Removing the guidance fixtures
- Remove the child restraint according the child restraint
manufacturer's instructions.
- Push down on the seat cushion so that the lower anchor ­
ages are visible.
- Pull off the guidance fixtures from the lower anchorages.
- Always remove the guidance fixtures and keep them in a
safe place when not in use.
You may find it easier to install child restraints equipped with hooks
attached to straps without the guidance fixtures in place. If this is
the case, remove the guidance fixtures by pulling them off the
anchorages. However, the guidance fixtures can help you to locate
the
LATCH anchorages.
& WARNING
Improper use of tether anchorages or lower anchorages can cause
serious personal injury in a crash.
Controls and equip­ ment Safety first Vehicle operation
& WARNING
(continued)
• Always carefully follow the child restraint manufacturer's
instructions for proper installation and use of child restraint
systems.
• Never use the
LATCH or tether anchorages to attach safety
belts or other kinds of occupant restraints.
• Child restraint tether attachments and lower attachments are
only designed to secure a child restraint that has been equipped
to use these anchorages.
• Tether anchorages and lower anchorages are designed to with­
stand only those loads imposed by correctly fitted child restraints.
Under no circumstances can they be used safely for adult or child
safety belts or harnesses.
• Never mount more than one child restraint to a single tether or
to a lower anchorage point. Attaching two child restraints to a
single anchorage point can cause the anchorage to fail and cause
serious personal injury in a crash.
0 Note
• Remove the guidance fix tures before folding the rear seatback to
prevent damaging the seat cushion.
• If you leave the guidance fixtures ins talled for several days , they
could leave a mark on the upholstery on the seat cushion and back ­
rest in the area that the guidance fixtures were ins talled. The uphol­
stery would also be permanently stretched around the guidance
fixtures. This applies especially to leather seats .
[ i] Tips
• Always remove the guidance fixtures when not in use.
• Please keep the guidance fixtures in a safe place with the vehicle
when not in use .•
Vehicle care Do-it-yourself service Technical data

-Child Safety
P'U:1--''-----------------
-Guide the upper tether strap under the rear head
restraint=> fig. 198 (raise the head restraint if necessary).
-Tilt the recess flap -detail view -=> fig. 198 up to expose
the anchor bracket.
-Slide the tether strap hook over the anchor bracket.
-Pull on the tether strap hook so that the spring catch of
the hook engages.
-Tighten the tether strap firmly following the child
restraint manufacturer's instructions.
Releasing the tether strap
-Loosen the tension following the child restraint manufac ­
turer 's instructions.
-Depress the spring catch on the hook and release it from
the tether anchor .
& WARNING
Always read and heed all WARNINGS.
0 Note
If you leave the child restraint with the tether strap firmly installed
for several days, this could leave a mark on the upholstery on the
seat cushion and backrest in the area where the tether strap was
installed. The upholstery would also be permanently stretched
around the tether strap . This applies especially to leather seats.•

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Intelligent technology
Notice about data recorded by
vehicle control modules
Your vehicle is not equipped with an Event Data Recorder (EDR),
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 retrieval 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 example, engine function, emission control, as
we ll
as for the airbags and safety belts.
These electronic control modules also record vehicle-related data
during normal vehicle operation for diagnostic 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 well 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 stability.
(X) CD
Fig. 199 Center
console with ESP
sw itch
ESP is designed to he lp you maintain vehic le control in situations
where the car approaches the limits of "grip", especial ly when
acce lerating and cornering. ESP reduces the risk of skidding and
improves stability under al l road conditions.
The system operates across the entire speed range in combination
with the ABS system . If the Anti-Lock Brake System (ABS) malfunc ­
t ions, the ESP will a lso shu t down.
How the system works
The Anti-Lock Brake System (ABS), Electronic Differential Lock (EDU
and the Anti -Slip Regu lation System (ASR) are integrated in the e lec ­
tronic stabilization program . In addition to the data provided by
these functions, the ESP control unit requires additional measure ­
ment data provided by high performance sensors. The rotational
.,,.

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speed of the vehicle about its vertica l axis, the lateral acce leration
ac ting on the veh ic le, the brake pressure and the s teering ang le a re
a ll measured .
The direction in which the driver wishes to travel is determined with
the aid of the steering angle and veh icle 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 la ning on a
wet road -
, ESP will au tomatical ly brake the appropria te wheel to
correct the problem .
The vehicle is then stabi lized by the forces acting on the whee l
during braking . If the vehicle is
oversteering (r ea r tends to skid out
of the turn), t he brakes are main ly 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 bra kes are applied at the
rear whee l that is on the inside of the curve. An acoustic signal indi ­
cates when ESP brake appl ication cuts in
=> & .
The system operates across the entire speed range in combination
wi th the ABS system
~ page 240. If the Ant i- Lock Brake Sys te m
(ABS) malfunctions, the ESP wi ll be out of act ion as well.
Ac tivat ion
When you turn on the engine, ESP will automatica lly be activated
and will perfo rm a self -test.
You can activate a deactivated ESP or deact ivated ASR as requ ired
by pressing the
=> page 236, fig. 199 button.
D eac tiva tion
Norma lly, the ESP should always be on .
When necessary, you can deact ivate Anti -Slip Regulat ion (ASR) or
the Electronic Stabilization Program (ESP) by pressing the button
=> page 236, fig. 199 .
• Dea ctivating A SR: Tap briefly on the ESP button . In certain excep ­
t iona l situations (e .g. driving wit h tire chains or a t a forced pace
around a track), the Anti-S lip Regu lation (ASR) can be deactivated
Controls and equip­
ment Safety first Vehicle operation
=> page
238 . The ESP check light flashes . T ap the ESP button again
t o r eact ivate ASR. The ESP check light g oes out .
• Deactiv ating ESP : Press the ESP button for more than 3 seconds .
W ith ESP deactivated, the ESP check ligh t illum inates cons tant ly .
Press the ESP button again to reactivate ESP . The ESP check light
g o es out .
& WARNING
The Electronic Stabilization Program i s neve rthele ss subject to the
laws of physi cs . It is part icularly important to pa y attent ion to thi s
fact on we t and slippery roads . It is therefore important that you
always adapt your driving to the condit ion of the road and traffic
c onditions. Do not allow the inc reased safety provided by the Elec ­
tronic Stabiliz ation Program sy stem to lull you into a ccepting
additional safety ri sk s.
• Plea se note that when ESP or ASR is dea ctivated , the drive
wheels can spin on icy and slippery roads and the vehicle can
break a way -da nger of skidding! •
Electronic differential lock (EDL)
The elec tr o nic differen tial l ock mon itors t he r ota tion al
speed of the drive wheels .
Gener al not es
The elec tronic d if f erential l ock (EDU helps the ca r to start mov ing,
accelerate and c limb a grad ient on surfaces providing poor or
a lmost n o grip. W ithout EDL, th is w ould be difficult, if no t impos ­
sib le.
How the system works
The EDL operates automatical ly. It monitors the rotational speed of
the drive whee ls on an ax le with the he lp of t he ABS senso rs
=> page 2 40 . If a noticeable difference in rotational speed between
the drive wheels on one axle is de tected (e .g. on sl ippery grou nd
on .,,.
Vehicle care Do-it-yourself service Technical data

-Intelligent technology
------~----- ~~--------------------------------------
one side), the spinning wheel is braked, thereby transferring power
to the other drive wheel or wheels (all- wheel drivel. 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.
Driving off
When driving off, always be sure to keep road conditions in mind as
you accelerate. If one drive wheel spins because it is on a surface
with less grip, gradual ly increase the pressure on the accelerator
pedal until the car starts to move. The wheel less able to transfer
power spins.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads, the EDL cuts out temporarily. The
veh ic le remains operational and behaves in the same way as a
vehic le without EDL.
As soon as the brake has cooled down, EDL switches on again auto ­
matically.
& WARNING
• When accelerating on slippery surfaces, such as on ice or snow,
always be careful when depressing the accelerator pedal. Even
with the EDL working, the drive wheels can spin and reduce your
ability to control your car . - Risk of crash!
• The increased safety afforded by EDL does not mean that you
ca n take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i ] Tips
If a fault occurs in the ABS, the EDL is also not functioning. This is
indicated by the ABS warning
light => page 21. •
Anti-Slip Regulation System (ASR)
The Anti-Slip Regulation System prevents the driven
wheels from spinning when the car is accelerating.
General notes
The Anti-Slip Regulation System (ASR) is integrated in the electronic
stabilization program (ESP) . When the vehicle starts up and acceler­
ates, the wheels are prevented from sp inning by adjus tin g the
engine power to match the amount of grip availab le from the road
surface.
How the system works
ASR performs automatical ly, i.e . w ithout the driver's intervention.
With the aid of the ABS
sensors=> page 240, ASR monitors the
speed of the driven wheels. If the wheels start to spin, the engine
power is reduced automatically until the tires find enough grip to
lock onto the road surface. The system is active across the entire
speed range.
The ASR works in conjunction with the ABS. If a malfunction shou ld
occur in the ABS, the ASR will also be out of act ion.
Activation
The ESP is automatica lly activated when the eng ine is started, and
it performs a self-test. You can activate a deactivated ASR, if
requ ired, by pressing
t h e=> page 236, fig . 199 button .
Deactivation
You can deactivate the ASR, if required, by pressing the button (for
less than 3
seconds) => page 236, fig. 199. With the ASR deactivated,
the ESP check light flashes,
see=> page 22.
Normally, the ESP shou ld always be on, however, it may be advanta­
geous to turn off the system in certai n special cases when some
degree of wheel spin is desired such as :
• when driving with snow chains