sensor AUDI S8 2010 Owner's Guide

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• A sensor in the safety belt latch for t he driver and for the front
sea t passenge r that senses w hether t hat s afe ty bel t is la tc h ed or not
and transmits this information to the electron ic cont rol un it .
& WARNING
Damage to the front passenger seat can prevent the front airbag
from working properly .
• Improper repair or disassembly of the front passenger and
driver seat will prevent the Advanced Airbag Sy stem from func ­
tioning properly.
• Repairs to the front passenger seat mu st be performed by qual­
ified and properly trained wo rkshop personnel.
• Never remove the front passenger or driver seat from the
vehicle.
• Never remove the uphol stery from the front passenger seat.
• Never disas semble or remove parts from the seat or disconnect
wires from it.
• Never carry sharp object s in your pockets or place them on th e
seat.
If the weight -sens ing mat in the passenger seat is punctured
it cannot work properly.
• Never carry things on your lap or carry objects on the passenger
s eat. Such items can in crease the weight regi stered by the weight ­
sensing mat and send the wrong information to the airbag control
unit.
• Never store items under the front passenger seat. Parts of the
Advan ced Airbag Sy stem under the pass enger seat could be
damaged, prevent ing them and the airbag system from working
properly.
• Never place seat covers or replacement upholstery that have
not been specifically approved by Audi on the front seat s.
• Seat covers can prevent the Advanced Airbag System from
recognizing child re straints or occupants on the front pas senger
seat and prevent the side airbag in the seat backrest from
deploying properly .
& WARNING (c on tinued )
• Never u se cushions , pillow s, blankets or s imilar items on the
front passenger seat . The additional padding will prevent the
weight-sens ing mat in the seat from accurately registering the
child restraint or person on the seat and prevent the Advan ced
Airbag System from functioning properly .
• If you must use a child restraint on the front passenger seat
and the child restraint manufacturer's instructions require the use
of a towel, foam cushion or something else to properly po sition
the child restraint , make certain that the PASSENGER AIR BAG
OFF light come s on and stay s on whenever the child re straint is
i nstalled on the front passenger seat.
• If the PASSENGER AIR BAG OFF light does not come on and
stay on , immediately install child restraint in a rear seating posi­
tion and have the airbag system inspected by your Audi dealer. •
How the Advanced Airbag System
components work together
Th e front Advanced A irbag System and the side airbags sup plement
the protect ion offered by the fro nt three -po int safety belts with
pretens ioners and load lim iters a nd the adjustable head restra ints to
he lp red uce the risk of i nju ry in a wide range of accident and crash
si tua tions. Be su re to re ad the impo rtan t info rmat ion about safe ty
and heed the WARNINGS in this c hapter.
Deploy ment o f the Advan ced Air bag Sys tem and t he activ ation o f the
safety belt pretensioners depend on the deceleration measured by
the crash sensors and registered by the electronic contro l u ni t. Crash
sever ity depe nds on speed and decelerat ion as well as the mass a nd
st iffness of the ve hicle or object invo lve d in the crash.
W hen the elect ronic contro l uni t reg isters a low sever ity cras h and
the safety belt is being used, the airbag will not dep loy . If the safety
be lt i s no t being used , the fi rs t sta ge dep loy s, followed by t he second
stage after a much later time in the crash sequence. ..

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& WARNING (co ntinued )
• Always make sure that the side airbag can inflate without
interference:
-Never install se at 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 sy stem 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 sy stem can be deployed only onc e. After an airbag
has been deployed, it must be replaced w ith new replacement
parts de signed and approved es pecially for your Audi model
version . Replacement of complete airbag 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.
• For safety reasons in severe accidents, the alternator and
starter are separated from the vehicle battery with a pyrotechni c
circuit interrupter .
- Work on the pyrotechnic circu it interrupter must only be
performed by a qualified dealer -risk of an a ccident!
- If the vehicle or the circu it interrupter is scrapped, all appli­
cable safety precautions must be followed .
Controls and equip­ ment Safety first Vehicle operation
<£' For the sake of the environment
U
ndeployed airbag modules and pretens io ners mig ht be classified as
Perch lorate Material -sp ec ial handling may a pply, see
www.d ts c. ca.gov/ha za rdouswaste/pe rchlorate . W he n t he vehicle or
parts of the restraint system including airbag modules and safety
bel ts wi th prete nsio ners are scra pped, all applica ble laws an d regula­
tions m ust be observed. Your authorized Aud i dea ler is familiar with
t hese requireme nts and we recommend tha t you have you r dealer
perform this service for you. •
Other things that can affect Advanced
Airbag performance
Chang ing the ve hicle's suspension system can change the way that
t he Adv anced Airbag System pe rforms in a crash . For example, using
tire-r im combinations not approved by Aud i, lower ing t he veh icle,
c hang ing the st iffness o f the suspe nsio n, incl uding the s prings,
s u spension str uts, shoc k absorbe rs etc. can change the forces that
are meas ured by the airb ag sensors and sen t to the ele ctron ic con trol
uni t. Some suspension changes ca n, for examp le, increase the force
levels measu red by t he sensors and ma ke the airbag sys tem dep loy in
crashes in which it wou ld not deploy if the changes had not bee n
made . Other kin ds of c hanges may re duce the force levels meas ured
by the senso rs and p revent the airbag from dep loyi ng when it should .
The sensors in the safety belt buckle for the d river and front
p assenger se at tell the e le ct ro nic co ntro l mo dule if the sa fe ty belt is
latc hed or not . If the safety be lt is be ing used, the fron t airbag w ill
dep loy at a s ligh tly hig her ra te o f ve hicl e decelerat io n t han if the
safety belt is not be ing us ed. T he refo re, in a part icular collis io n, it is
poss ible that an a irbag wi ll not deploy at a seating posit ion where the
safety belt is being used but wi ll inflate at the posi tion whe re the
safety belt is not bei ng used. It is important that not hing interfere
w ith the s afe ty be lt bu ckles so t hat th e sensor s can sen d the correct
information about safety belt use to the electronic contro l unit. ..
Vehicle care Do-it-yourself service Technical data

-Airbag system PHI- --=--=----------------
& WARNING
Changing th e vehicle 's su spension including use of unappro ved
tire -rim c ombination s can change Advan ced Airbag performan ce
and increas e the risk of serious personal injury in a cra sh .
• Never install suspension component s that do not have the
same performance characteristics as the components or iginally
installed on your veh icle.
• Never u se tir e-rim combinations that have not been approved
by Audi.
& WARNING
Item s stored be tween the safety belt buckl e and the center
console can cause the sensors in the buckle to send the wrong
information to the ele ctroni c control module and prevent the
Advanced Airbag System from w orking properl y.
• Always make sure that nothing can interfere with the safety
belt buckles and that they a re not obstru cted .
<£> For the sake of the environment
Undeployed airbag modu les and pretensioners might be class ified as
Perc hlorate Mate rial -spe cial ha ndling may apply , see
www.dtsc.ca.gov/hazardouswaste/pe rchlorate . When the vehicle or
p arts of t he rest raint sys tem including a irbag mod ules and safe ty
belts with pretensioners are scrapped, all applicable laws and regula­
tions must be observed . Your authorize d Audi dea ler is familiar with
these requirements and we recommend that you have yo ur dealer
perform this serv ice for you. •
Knee airbags
Description of knee airbags
The airbag system can provide supplemental protect ion
to properly re str ained f ro n t seat occupants.
0
Fig. 21 6 Driv er' s
a ir ba g
The a irbag for the dr iver is located in the inst rument pane l under­
neath the steering wheel~ fig . 216, t he airbag for the passenger is
at abo ut the same height in t he instr ument panel underneath the
glove compartment.
Th e knee airbag offers addit ional protec tion to the dr ive r's and
passenger's knees and upper and lower thigh areas as a s upplement
t o the sa fety bel ts.
If the front a irbags dep loy, the knee airbags a lso deploy i n frontal
co llisions above a certain severity~
page 215, "More importan t
t hings to know abou t front airbags ".
Besides the ir no rma l safety function , safety belts work to help keep
t he drive r o r front passenger in po sit ion in c ase of a frontal collision
so that the a irbags can provide protection .
Th e airbag system is not a substitute for your safety belt . Rather, it is
pa rt of the ove rall occ upant re st ra int system in your veh icle. Always
remember t hat the airbag system can on ly help to protect you if you
are wearing your safety be lt and wear ing it pr operly . T his is why you ..

Side airbags
Description of side airbags
The airbag system can provide supplemental protection
to properly restrained occupants .
Fig. 218 Side airbag
locat ion in the driver's
seat
The side airbags are located in the sides of the front seat backrests
=> fig. 218 and the rear backrest facing the doors. They are identified
by the word "AIRBAG" .
The side airbag system basically consists of:
• the electronic control module and external s ide impact sensors
• the two side airbags located in the sides of the front backrests
• two rear side airbags
• the airbag warning light in the instrument cluster.
Th e airbag system is mo nitored electronically to make certain that it
is funct ion ing properly at all times. Each time you turn on the igni­
tion, the airbag system indicator light wi ll come on for a few seconds
(self diagnostics).
The side airbag system supplements the safety belts and can help to
reduce the risk of injury to the driver's, front and rear passenger's
upper torso on the side of the vehicle that is struck in a side collision.
The air bag deploys on ly in s ide impacts and only when the vehicle
acceleration registered by the contro l unit is high enough. If this rate
Safety first Vehicle OP-eration
Airbag system
is below the reference value programmed into the control unit, the
side airbags will no t be triggered, even though the car may be badly
damaged as a result of the collision . It is not poss ible to define an
airbag triggering range that wi ll cover every possib le angle of impact,
since the circumstances will vary considerably between one collision
and another . Important factors include, for example, the nature
(hard or soft) of the impacting object, the angle of impact, vehicle
speed, etc.=>
page 226, "Important safety instructions on the s ide
airbag system".
Aside from their normal safety function, safety belts work to help keep the driver or front passenger in position in the event of a side
co llision so that the side 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 veh icle. Always
remember that the side airbag system can only help to protect you if
you are wearing yo ur safety belt and wearing it properly. This is
another reason why you should always wear your safety belts, not just
because the law requires you to do so=>
page 197, "Genera l notes".
It is important to remember that while the supp lemental side airbag
system is designed to reduce the likelihood of serious injuries, other
injuries, for example, swelling, bruising, and minor abrasions can
also be associated with deployed side airbags. Remember too, side
airbags will dep loy only once and only in certain kinds of accidents -
your safety belts are always there to offer protection.
Vehicle damage, repair costs or even the lack of vehicle damage are
not necessarily an indication of over-sensitive or failed a irbag activa­
tion. In some collisions, both front and side airbags may inflate .
Remember too, that airbags will deploy only once and on ly in certain
kinds of collisions -your safety belts are always there to offer protec­
tion in those accidents in wh ich airbags are not supposed to deploy o r
when they have already deployed.
The side airbag system will not deploy:
• when the ignition is turned off
• in side collisions when the acceleration measured by the sensor is
toolow
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Vehicle care Do-it-yourselt service iTechnical data

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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
interference.
- 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 (cont
inued)
• Always 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 side airbag deployment and can
cause personal injury in an accident.
• 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.) 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 231, "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

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Side curtain airbags
Description of side curtain airbags
The side curtain airbag system can provide supplemental
protection to properly restrained occupants .
Fig. 220 Side curtain
airbags, driver's side:
s ide curtain airbag
location
The side curtain airbags are located on both sides of the interior
above the front and rear side windows=> fig. 220. They are identified
by the word "AIRBAG" on the windshield frame and the center roof
pillar.
The side curta in airbag system s upplements the safety belts and can
help to reduce the risk of injury for occupants' heads and upper torso
on the side of the vehicle that is struck in a sid e collision . The s ide
curtain a irbag inflates only in side impacts and only when the vehicle
acceleration registered by the contro l unit is high enough . If this rate
is below the reference value programmed into the control unit, the
side airbags will not be triggered, even though the car may be bad ly
damaged as a result of the collision.
It is not possib le to define an
airbag triggering range that will cover every possible angle of impact,
since the circumstances will vary considerably between one collision
and another. Important factors include, for example, the nature
(hard or soft) of the impacting object, the angle of impact, vehicle
speed, etc.=>
page 229, "How side curtain airbags work" . Aside from their normal safety function, safety belts work to help
keep the driver or front passenger in position in the event of a co lli­
sion so that the s ide curta in a irbags 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 veh icle. Always
remember that the airbag system can on ly help to protect you if you
are wear ing your safety belt and wearing it p rop erly . This is another
reason why you should always wear your safety belts , not just because
the law requires you to do so=>
page 197, "Gene ral notes".
It is important to remember that while the side curta in airbag system
is designed to he lp reduce the like lihood of serious injuries, other
injuries , for example, swell ing, bruis ing, and minor abrasions can
also be assoc iated with these airbags upon deployment. Remember
t oo, these airbags wi ll dep loy only once and only in certain kinds of
accidents - your safety belts are always there to offer protection .
The side curtain airbag system basically consists of:
• The electronic control module and external side impact sensors
• The side curtain airbags above the front and rear s ide windows
• Th e airbag indicator light in the instrument panel
The airbag system is mon itored electron ically to make certain it is
functioning properly at all times . Each time you turn on the ignition,
the air bag system indicator light will come on for a few seconds (self
diagnostics).
The side curtain airbag is not activated:
• if the ignition is turned off,
• in side co llisions when the acceleration measured by the sensor is
too low,
• in front-end collisions,
• in rea r-end co llisions,
• in rollovers .

-----------------------------------------~C~ h~il ~d ~ S~a _!fe ~ t !;YL __
and for the different models of the same kind of child restraint
offered by child restraint manufacturers.
The weight ranges for the individual types, makes and models of ch ild
restraints that the NHTSA has specified in the Safety Standard
together with the weight ranges of typical infants and typical 1 year­
old child have been stored in the control unit of the Advanced Airbag
System. When a child restraint is being used on the front passenger
seat with a typical 1 year-old chi ld, the Advanced Airbag System
compares the weight meas ured by the weight sensing mat with the
information stored in the electronic control unit .
The electronic contro l unit a lso registers the tension on the front
passenger safety belt. The tension on the safety belt for the front
passenger seat will be different for an adult who is properly using the
safety belt as compared to the tension on the belt when it is used to
attach a child restraint to the seat . The sensor below the latch for the
safety belt for the front seat passenger measures the tension on the
belt. The input from this sensor is then used with the weight to
"decide", whether there is a child restraint with a typical 1 year-old
child on the front passenger seat and whether or not the airbag must
be turned off .•
Child restraints and Advanced Airbags
Regardless of the child restraint that you use, ma ke sure that it has
been certified to meet United States Federal Motor Vehicle Safety
Standards and has been ce rtified by its manufacturer for use with an
airbag . Always be sure that the child restraint is properly installed at
one of the rear seating positions. If in exceptional circumstances you
must use it on the front passenger seat, carefully read all of the infor­
mation on ch ild safety and Advanced Airbags and heed all of the
app licab le WARNINGS. Make certain that the child restra int is
correctly recognized by the weight-sensing mat inside the front
passenger seat, that the front passenger airbag is turned off and that
the airbag status is always correctly signaled by the
PASSENGER AIR
BAG OFF
light.
Controls and equip­ ment Safety first Vehicle operation
Many types and models of child restra
ints have been available over
t he years, new models are introduced reg ularly incorpo rating new
and improved designs and older models are taken out of product ion.
Chi ld restraints are not standardized. Child restraints of the same
type typ ically have d ifferent weights and sizes and differe nt 'foot­
prints,' the size and shape of the bottom of the child restraint that
sits on the seat, when they are installed on a vehicle seat . These
differences make it virtually impossib le to certify compliance with
t he requirements for advanced airbags with each and every chil d
restra int that has ever been sold in the past or will be sold over the
course of the useful life of your vehicle.
For this reason, the United States Nationa l Highway Traffic Safety
Administration has published a list of specific type, makes and
mode ls of child restra ints that must be used to cert ify compliance of
the Advanced Airbag System in yo ur vehicle with the suppression
requirements of Federal Motor Veh icle Safety Standard 208. These
child restraints are:
A. Car beds, manufactured on or after September 1,
2004:
• Cosco Dream Ride 02-719
B. Rear facing child restraint systems,
manufactured on or after September 1, 2004:
(When the restraint system comes equipped with a removable base,
compliance has to be cert ified with or without the base) .
• Britax Handle with Care 191
• Century Assura 4553
• Century Smart Fit 4543
• Cosco Arriva 02727
• Evenflo Discovery Adjust Right 212
• Evenflo First Choice 204
• Graco Infant 8457
Vehicle care Do-it-yourself service Technical data

Intelligent technology
'-----------------------------------------------
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 retrieva l after an accident or crash event. ED R's are
sometimes called "crash recorders".
Some state laws restrict the retrieval or downloading of data stored
by ED R's that were installed 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 w ith
a number of electronic control modu les for various vehicle systems
such as, for example, engine function, emission control, as well as for
the airbags and safety belts.
T hese electronic contro l modules also record vehicle-re lated data
during normal vehicle operation for diagnostic and repair purposes .
Th e recording capacity of the e lectronic control modu les is limited to
data (no sound is recorded) and only a sma ll amount of data is actu­
ally 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 vehicle speed, direction, 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.
N
-. ...
~
I ' I A I ~ )
--
Fig. 234 Center
console with ESP
switch
ESP is des igned to help you maintain vehicle control in s ituations
where the car approaches the limits of "grip", especia lly when accel­
erat ing and cornering. ESP reduces the risk of skidd ing and imp roves
stability under all road conditions.
Th e system operates across the entire speed range in combination
with the ABS system. If the Anti-Lock Brake System (ABS) malfunc­
tions, the ESP will also shut down.
How the system works
The Anti-Lock Brake System (ABS), Electronic Differential Lock (EDL)
and the Anti-Slip Regulation System (ASR) are integrated in the elec­
tronic stabilizatio n pro gram. In addition to the data provided by
these funct ions, the ESP control unit requires additional measure­
ment data provided by high performance sensors. The rotational
speed of the vehicle about its vertical axis, the lateral acceleration ...

_________________________________________ I_ n_ t_ e_ ll_,igent technology ,__E~-
acting on the vehicle, the brake pressure and the steering angle are
all meas ured.
The direction in which the driver wishes to travel is determined with
the aid of the steering angle and vehicle speed and is continually
compared with the actual behavior of the vehicle. If the two do not
match, for example , when the vehicle starts hydroplaning on a wet
road, ESP will automatically brake the appropriate 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 (rear tends to skid out of the
turn), the brakes are main ly applied on the wheel that is on the
outs ide of the curve. In the case of a vehicle that is
understeering
(tendency to slide out of the curve), the brakes are applied at the rear
wheel that is on the inside of the curve. An acoustic signal ind icates
when ESP brake application cuts in =>
&.
Th e system operates across the entire speed range in combination
with the ABS system=>
page 256. If the Anti-Lock Brake System
(ABS) malfunctions, the ESP will be out of action as we ll.
Activation
When you turn on the engine, ESP will automatically be activated and
will perform a self-test .
The system can be activated or deactivated by pressing the button
=>
page 252, fig. 234 . The warning light comes on when the system
is switched off=>
page 16.
Normally, the ESP should always be on, however, it may be advanta­
geous to turn off the sys tem in certain special cases when some
degree of whee l spin is desired such as:
• when driving with snow chains
• when driving in deep snow or on a loose surface (to allow the
wheels to dig in to reach firm ground)
• when trying to "roc k" the vehicle free when it has become stuck.
The system should be reactivated once you are no longer in such situ­
ations.
Controls and equip­ ment Safety first Vehicle operation
Both the ABS and
EDS systems are still functioning even if the ESP is
switched off.
& WARNING
The Electroni c Stabilization Program is nevertheless subject to the
laws of physics. It is particularly important to pay attention to
this fact on wet and slippery roads. It is therefore important that
you always adapt your driving to the condition of the road and
traffic conditions. Do not allow the increased safety provided by
the Electronic Stabilization Program system to lull you into
accepting additional safety risks. •
Electronic differential lock (EDL)
The electronic differential lock monitors the rotational
speed of the drive wheels.
General notes
The electronic differential lock (EDL) helps the car to start moving,
acce lerate and climb a gradient on surfaces providing poor or almost
no grip . Without EDL, this would be difficult, if not impossible .
How the system works
The EDL operates automatically. It monitors the rotational speed of
the drive wheels on an axle with the he lp of the ABS sensors
=>
page 256 . If a noticeable difference in rotational speed between
the drive wheels on one axle is detected (e .g . on slippery ground
on
one side),
the spinning wheel is braked, thereby transferring power to
the other drive whee l or wheels (all -wheel 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 contro lled.
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 , gradually increase the pressure on the accelerator peda l
Iii>
Vehicle care Do-it-yourself service Technical data

Intelligent technology
'-----------------------------------------------
until the car starts to move . The whee l less ab le to transfer power
spins .
Overheating of brakes
To prevent the disc b rake of the bra ked wheel from ove rhea ting if
subjected to excessive loads, the EDL cuts out temporarily . The
veh icle remains operat ional and beh aves in the same way as a vehicle
without EDL .
As soon as the brake has coo led down, EDL switches on again auto­
matically .
& WARNING
• When a ccelerating on slippery surfaces, such as on ice or snow,
alw ay s be careful when depre ssing the a ccelerator pedal. E ven
with the EDL working, the drive wheel s can spin and reduce your
ability to control your car . Risk of crash !
• The in creased safety afforded by EDL does not mean that you
can take safety ri sks. Always adapt your driving st yle to the road
condition s and traffic situation .
fi Tips
If a fault occurs i n the ABS, the EDL is also no t fu nct ion ing . This is
indicated by the ABS warning light~
page 19. •
Anti-Slip Regulation System (ASR)
The Anti-Slip Regulati on System prevents the driven
wheels from spinning when the car is a ccel erating.
General notes
T he Anti-S lip Regulation System (ASR) is integrated in the electronic
stabilization program (ESP). When the veh icle starts up and acceler­
ates , the wheels are p reve nted from sp inning by adjust ing the eng ine
powe r to match t he amo unt of grip avai lab le from the road s urface.
How the system works
ASR perfo rms au toma tica lly, i .e . witho ut the drive r's in tervent ion .
With the aid of the A BS sensors~
page 256, ASR monitors the speed
of the driven wheels . If the wheels start to spin, the engine powe r is
reduced automat ically u nti l the t ires find enough gr ip to lock onto
the road s urface. The system is active across the entire speed range.
Th e ASR wor ks in con ju nction with the A BS .
If a m alfu nction sho uld
occur in the ABS, the ASR w ill also be out of action.
& WARNING
The increased safety afforded by ASR does not mean that you can
take safety ri sks . Always adapt your driving style to the road
condit ions and traffic situation.
[ i ] Tips
To ensure that the ASR works prope rly, all four wheels must be fitted
w ith ident ic a l ti res Any differences in rollin g radius of the tires can
cause the system to reduce engine power when t his is not desired .
See also ~
page 318, "N ew t ires and replacing tires and whee ls" .•
Braking
General Information
What affects b raking efficiency ?
Operating cond itions and driving habits
Th e bra kes on t oday's automo biles are still subjec t to we ar,
depending large ly on operating conditions a nd driving habits~ &.
O n ve hicles tha t are eithe r driven mostly in stop- and-go city t raff ic or
are drive n hard, the brake pads should be checked by your author ized
Audi de aler more o ften than specified in the
Warranty & Mainte­
nance booklet .
Failure to have your brake pads i nspected can result
in re duced brake pe rformance. .,