sensor AUDI A5 CABRIOLET 2010 Service Manual

-Airbag system
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PASSENGER AIR BAG OFF light
Fig. 200 Sec tion from
the in strume nt panel :
PASSENGER AIR BAG
OFF light
The PASSENGER AIR BAG OFF light is located in the center of t he
ins trumen t panel => fig.
200.
T he PASSENGER AIR BAG OFF ligh t will com e on and stay on to te ll
you when the front Advanced Airbag on the passenger side has been
t u rn ed off by the ele ct ronic contro l uni t. Each t ime you t urn on t he
ign ition, the
PASSENGER AIR BAG OFF lig ht will flas h fo r a few
se co nds and:
• will stay on if the front passenger seat is not occupied,
• will s tay on if t here i s a small ch ild or child re str ain t on the fron t
passenger seat,
• will go out if t he fron t passenger seat is oc cupied by a n adul t as
registered by the weight-sensing mat .
Th e
PASSENGER AIR BAG OFF light mu st come on and stay on if the
ign ition is o n and
• a ca r bed has been installed o n the front seat, or
• a rearward -facing child restraint has been insta lled on t he front
passenger seat, o r
• a forward-fac ing ch ild restraint has bee n installed on the front
passenge r seat, o r
• the weight registered on t he front passe nger seat is equal to o r
less th a n the co mb ined we ight of a typic al 1 year-o ld rest rained in one of the rear-fac
ing or forward-facing infant restraints listed in
F e d era l Mo tor Ve hicle Safe ty St anda rd 2 08 w ith which th e Adv anced
Airbag System in your vehicle was cert ified.
If the front passen ger seat is not occ upied, the front airbag will not
dep loy, and t he
PASSENGER AIR BAG OFF ligh t will stay on. Never
install a rearward -facing c hild rest raint on the f ront passenger seat,
t he s afest pl ace fo r a child in any kin d of child re stra in t is a t one o f th e
seating pos it ions on t he rear seat::::;,
page 202, "Child restra ints on
t he fro nt sea t - so me im port an t things to kno w" and ::::;,
page 222,
"Ch ild Safety".
If the PASSENGER AIR BAG OFF light comes on when one of the
c onditions lis ted above is met, be sure to check the lig ht reg ularly to
ma ke certain that the
PASSENGER AIR BAG OFF li ght stays on
c ont inuous ly whenever the ignition is on. If the
PASSENGER AIR BAG
OFF
light does not appear and not stay on all the t ime , stop as soon
as it is safe to do so and
• reactivate the system by turn ing the ig nition off and then tur ning
it on again;
• remove and reinstall the child restraint. Make sure that the c hild
restrain t is properly insta lled and that the sa fety belt for the fron t
passenger seat has been correctly ro uted around the child restraint as
described in the child res trai nt ma nufactu rer's instr uctions;
• make su re that the convertib le lock ing feature on t he safety belt
f or the front passenger sea t has been act ivate d an d that the safe ty
belt has bee n pulled tight. The belt m ust not be loose or have loops
of slac k so that t he senso r be low the safety belt latc h on the seat can
do its job::::;,
page 232 .
• make s ure tha t things tha t may in crease the weight o f the chi ld
and child safety seat are not be ing transported on t he front
passenge r seat;
• make sure that the safety belt tension sensor is not blocked .
Shake the sa fety belt la tch on the front passenger seat back and
forth;
• If a st rap o r tether i s be ing u sed t o tie the c hild safety sea t to the
front passenger seat, make sure that it is not so tig ht that it causes .,_

_____________________________________________ A ~i..:_r ,::b :=:a ~g !...:: s'.:!y '..:s~ t~ e ~ m~ --
& 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 st e m 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.
• In accidents when an airbag is deployed, the vehicle battery
separates the alternator and the starter from the vehicle electrical
system for safety reason s with a pyrotechnic 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 -special handling may app ly, see
www.d ts c. ca.gov/ha za rdouswaste/pe rchlorate . W he n t he vehicle or
parts of the restraint system includi ng a irbag modules safety belts
w ith pretens io ners are s crappe d, all ap plic abl e laws and reg ulat ion s
must be observed. Your author ized Aud i dealer is familiar with these
req uir ements and we recommen d that yo u have yo ur dea le r pe rform
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 the 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 system dep loy in
crashes in which it wou ld not deploy if the changes had not bee n
made . Other kin ds of changes 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 used. 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

Ill Airbag system
---=---=----------------
& WARNING
Changing th e vehicle 's su sp en sion 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
b y Audi.
& WARNING
Item s stored b etween 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
Perch lorate Mate rial -special handling may app ly, 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 safe ty belts
w ith pretens ioners are scrapped, all applicable laws and regulat ions
must be observed. Your authorized Audi dealer is familiar with these
requ irements and we recommend that you have your dealer perform
this se rvice for yo u.•
Knee airbags
Applies to veh icles: w it h Knee a irbags
Description of knee airbags
The airbag system can provide supplemental protection
to properly restrained front seat occupants.
....
! 00 m
Fig. 201 D riv er's kn ee
a ir ba g
The knee airbag for the driver is located in the instrume nt panel
unde rneath the steering whee l:::> fig. 201, the knee airbag for the
passenge r is at about the same he ight in the instrument panel under­
neath the g love 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 supplement
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 209, "More importan t
things to know about front airbags" .
Besides the ir normal safety function, safety be lts work to help keep
t he drive r o r front passenger in po sit ion in c ase o f 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
part of the overall occ upant restra int system in your veh icle . Always
remember t hat the airbag system can on ly help to protect you if you
~

Side airbags
Description of side airbags
The airbag system can provide supplemental protection
to properly restrained occupants.
Fig. 203 Side airbag
location in the driver's
seat
The side airbags are located in the sides of the front seat backrests
=>
page 219, fig. 203. They are identified by the word "AIRBAG" .
The side airbag system basically consists of:
• the electronic control module and external side impact sensors
• the two side airbags located in the sides of the front backrests
• the airbag warning light in the instrument cluster.
The airbag system is monitored electronically to make certain that it
is functioning properly at all times. Each time you turn on the igni­
tion, the airbag system indicator light will 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 and front passenger's upper
torso on the side of the vehicle that is struck in a side collision. The
airbag deploys only in side impacts and only when the vehicle acceler­
ation registered by the control 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 badly
Safety first Vehicle OP-eration
Airbag system
damaged as a result of the collision. It is not possible 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 220, "Important safety instructions on the side
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
collision 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 vehicle. Always
remember that the side airbag system can only help to protect you if
you are wearing your 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 190, "General notes".
It is important to remember that while the supplemental 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 deploy 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 airbag activa­
tion. In some collisions, both front and side airbags may inflate.
Remember too, that airbags will deploy only once and only in certain
kinds of collisions -your safety belts are always there to offer protec­
tion in those accidents in which airbags are not supposed to deploy or
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
too low
• in front-end collisions
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Vehicle care Do-it-yourselt service iTechnical data

Airbag system -----------------=--=---
& WARNING (continued)
-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
cupholders, 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.
• Always prevent the side airbags from being damaged by heavy
objects knocking against or hitting the sides of the seatbacks.
Controls and equip­ ment Safety first Vehicle operation
& WARNING (cont
inued)
• 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 222, "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 ¥_Y __ _
& WARNING (c on tinued )
• Always install rearward-facing child safety seat s on the rear
seat .
• If you must install a rearward facing child safety seat on the
front passenger seat in e xceptional circumstance s and the
PASSENGER AIR BAG OFF light does not come on and sta y on,
immediately install the rearward-facing child safety seat in a rear
seating position and have the airbag system inspected immedi ·
ately by your authorized 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.
• Always follow the manufacturer's instructions provided with
the child safety seat or carrier.
• 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 po ssible before in stalling the child restraint. The back­
rest must be adjusted to an upright position.
• Alway s make sure that the PASSENGER AIR BAG OFF light
comes on and stays on all the time whenever the ign ition is
switched on .•
Advanced front airbag system and children
Your vehicle is equipped wi th a fron t "Adva nced Airbag Syste m" in
compliance with United States Federal Motor Vehicle Safety Standard
(FMVSS) 20 8 as app licable at t he time your ve hicle w as m anufa c­
tured.
Controls and equip­ ment Safety first Vehicle operation
T
he Advanced A irbag system in your veh icle has been ce rtified to
meet the "low-r isk" re quiremen ts fo r 3-and 6-ye ar old c hildre n on
t he passenger side and small ad ults o n the dr ive r side . The low r isk
deployme nt c riteria are intende d to reduce the risk of injury t hrough
in teraction with the airbag that can occ ur, for example, by being too
close to the steering w heel and i nstr ument panel when the ai rbag
inflates . In addi tion, the system has bee n certified to comp ly with the
"suppression" requirements of the Safety Sta ndard, to turn
off the
fr ont ai rbag for infan ts up to 12 month s w ho are rest rai ned on the
front passenger seat in child restraints t hat are listed in the Stan­
d ard .
Even thoug h your veh icle is eq uipped with an Advanced Airbag
system, a ll child ren, es pecially those 12 years and yo unger, should
always ride in the back seat pro perly r estra ined for the ir age and s ize.
T he airbag on the passenger si de makes the fro nt seat a potentially
dange rous place fo r a child to ride. The front seat is not the s afest
place for a c hild in a forward-facing c hild safety seat. It can be a very
dange rous place for a n infant or a larger ch ild in a rearward-fa cing
seat. •
Advanced Airbags and the weight-sensing
mat in the front seat
Th e Advance d Airbag System i n your vehicle detects the p resence o f
an in fant o r chil d in a c hild rest raint o n the front passenger seat using
the weight-sens ing mat in the seat cushion and the sensor be low the
safety belt latc h on t he fro nt passeng er seat that meas ures t he
tension on the sa fety belt.
Th e weigh t-sens ing m at me asures to tal weight of the ch il d and t he
child saf ety seat a nd a child blanket on the front passenge r seat . T he
we ight on t he front passenger seat is re lated to t he desi gn of the
child res traint and i ts "foot print", the size and shape of the bo ttom
of the chi ld restraint as it sits on the seat . The weight of a child
restra int a nd its " foo tprint" va ry for diffe re nt k inds of child res tra ints
~
Vehicle care Do-it-yourself service Technical data

-Child Safety ---- ~---------------------------
and for the different models of the same kind of child restraint
offered by child restraint manufactu rers .
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 typica l 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 measured by the weight sens ing mat with the
information stored in the electronic control unit .
T he electronic control unit also registers the tension on the front
passenger safety be lt . The tension on the safety belt fo r the front
passenger seat will be different for an adult who is properly using the
safety belt as compared to the tension on the be lt 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 we ight to
"decide", whether there is a child restraint with a typical 1 yea r-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, make sure that it has
been certified to meet United States Federal Motor Vehicle Safety
Standards and has been certified 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 chi ld safety and Advanced Airbags and heed a ll of the
applicable WARNINGS. Make certain that the child restraint 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. Many
types and models of child restra ints have been available over
the years, new mode ls are introduced regularly incorporating new
and improved designs and older models are taken out of production .
Chi ld restraints are not standardized. Child restraints of the same
type typically have different weights and sizes and different 'foot­
prints,' the size and shape of the bottom of the chi ld restraint that
sits on the seat, whe n they are installed on a vehicle seat. These
differences make it virtually impossible to certify compliance with
the requirements for advanced airbags with each and every child
restraint that has ever been sold in the past or w ill be sold over the
course of the useful lif e of yo ur vehicle.
For this reason, the United States National H ighway Traffic Safety
Administration has published a list of specific type, makes and
mode ls of child restraints that must be used to cert ify comp liance of
the Advanced Airbag System in your vehicle with the suppression
requirements of Fede ral Motor Vehicle Safety Standa rd 208. These
child restraints are:
A. Car beds, manufactured on or after September 1,
2004:
• Cosco Dream Ride 02-719
B. Rearward 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 certified w ith or w ithout 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

Intelligent technology
--------------------------------------------------' "---.L==--
The 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 integ rated in the elec­
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
speed of the vehicle about its vertical axis, vehicle acceleration in the
fore-and-aft and lateral directions, the brake pressure, and the
steering angle are all measured .
Th e direction in which the driver wishes to travel is determined with
the aid of the steering angle and vehicle speed and is con tinually
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 whee l to correct
the problem.
The vehicle is then stabilized by the forces acting on the whee l during
brak ing.
If the vehicle is oversteering (the vehicle turns too sharply
and the rear wheels slide toward the outside of a curve), the brakes
are mainly applied on the wheel that is on the outside of the curve. In
the case of a vehicle that is
understeering (the vehicle does not turn
sharply enough and pushes out of a curve), the brakes are applied as
needed on the wheel that is on the inside of the curve or additionally
on the other wheels. An acoustic signal indicates when ESP brake
application cuts in=> &.
The system operates across the entire speed range in combination
with the ABS system =>
page 245. If the Anti- Lock Brake System
(ABS) malfunctions, the ESP will be out of action as well.
Activating
When you turn on the engine, ESP will automatically be activated and
w ill perform a self-test. As soon as the test is comp leted, the system
is in normal operating mode.
Controls and equip­
ment Safety first Vehicle operation
You can activate a
deactivated ESP or deactivated ESP/ ASR if required
by pressing the =>
page 240, fig. 214 => page 240, fig. 213 button.
When they are activated, the message
ESP/ ASR on appears briefly
in the display.
Deactivating
The ESP should normally be activated all the time. If necessary, you
can deactivate Anti-Slip Regulation (ASR) or the Electron ic Stabiliza ­
tion Program (ESP) by press ing the button =>
page 240, fig. 214 .
• Deactivating ASR: Tap the button . In certain exceptional s itua­
t ions (e.g. driving with tire chains), the Anti-Slip Regu lation (ASR) can
be deact ivated =>
page 242. The message ASR off appears in the
display as we ll.
• Deactivating ESP/ASR Press the button for more than 3 seconds .
With the ESP/ASR deactivated, the ESP check light comes on, see
=>
page 14. The message ESP switched off appea rs in the display as
well.
& WARNING
The Electronic 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.
u
Vehicle care Do-it-yourself service Technical data

Intelligent t echnology
---------------------------------------
Electronic differential lock (EDL)
The elec tronic differen tial lock monitors the rotational
speed of the drive wheels.
G en era l not es
The electronic differentia l lock (EDL) helps the ca r to sta rt moving,
accelerate and climb a gradient on surfaces provid ing poor or almost
no grip . W ithout ED L, this would be d iff icu lt, if not impossible.
How the sy stem works
The EDL operates automatically. It mo nitors the rota tional speed of
wheels with the help of the ABS sensors=>
page 245. If a not iceab le
slip is detected at the wheels (e.g. on slippery g round on one side),
the spinn ing wheels are braked and power is transferred to the other
wheels . This is done up to a speed of about 60 mph (100 km/h).
No ises from the brake system signal that wheel sp in is being
controlled.
Driv ing off
When d riving off, always be s ure to keep road conditions in mind as
you accelerate. If one drive wheel spins because it is on a surface with
less grip, apply
plenty of throttle until the car starts to move.
O verheating of bra kes
To prevent the disc b rake of the bra ked wheel from ove rhea ting if
subjected to excessive loads on this wheel, the EDL cuts out tempo­
ra rily. The vehicle remains operat io nal and be haves in the same way
as a veh icle without EDL.
As soon as the brake has coo led down, EDL switches on again auto ­
matically.
Electronic limited slip differential
In vehicles w ith front wheel drive *, an e lectron ic lim ited slip d ifferen­
tial engages when driving on curves . The brakes are applied spec ifi­
cally to the front wheel that is on the inside of the curve. T his m ini­
m izes sliding on the front wheels and enables precise and neutral dr
iv ing t hrouge curves. The electronic lim ited slip differentia l does
no t engage whe n driving in we t cond it io ns or snow.
& WARNING
• Wh en acc elerating on slipp ery s urface s, such a s on ice or snow,
always be careful when depre ssing the accele rator pedal. Even
with the EDL and the electroni c limited slip differential working,
the dr ive wh eels can spin and reduce you r ability to control your
c ar . -Ri sk of cra sh!
• The increased safet y afforded b y EDL and the electronic l imited
slip differ ential d oes not mean th at you can take safety risks .
Alw ay s adapt your d riving st yle to the road c onditions and traffi c
si tuation.
[ i ] Tips
If a fa ult occurs in the ABS, the EDL is also not funct ioning. This is
ind icated by the ABS warn ing light=>
page 16 . •
Anti-Slip Regulation System (ASR)
The Anti-Slip Regulation System prevents the driven
wheels from spinning when the car is a ccelerating.
General notes
T he Anti-Slip Regu lation System (ASR) is in tegrated in the electronic
stabilization program (ESP) . When the veh icle starts up and acceler­
a tes, the wheels are preven ted from sp inning by adjust ing the engine
power to match the amount of grip ava ilable from the road surface.
How the system works
ASR performs automatica lly, i.e. without the driver's intervent ion.
With the a id o f the ABS sensors=>
page 245, ASR moni tors the speed
of the driven wheels. If the wheels start to spin, engine torque is
reduced automatically unti l the tires find enough grip to lock onto
the road s urface. The system is active across the entire speed range . .,

Intelligent technology
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Repl acing wheel s/tires
Vehicles wi th all wheel drive must a lways have tires of t he same size.
Also avoid tires with different tread depths. For details see page
=> page 307, "New tires and rep lacing tires and wheels".
Off -Road driving?
Your Audi does not have enough ground clearance to be used as an
off-road veh icle . It is therefore best to avo id ro ugh tracks and uneven
terrain as m uch as possible . Also refer to=>
page 251.
& WARNING
Alway s adju st your driving to road and traffi c conditi ons. Do not
let the ex tra safety afforded by all wheel dr ive tempt you into
taking extra risks.
• Although the all wheel dri ve is ve ry effecti ve, always
remember that braking capacity is limited by tire traction. You
should therefore not dri ve at ex cessive speeds on icy or slippery
road surfaces .
• On wet road surfaces , be careful not to drive too fast because
the front wheel s could begin to slide on top of the water (aqua­
planing ). If th is should occur, you will have no warning from a
sudden increase in engine speed as with a front-wheel drive
vehicle. Always drive at speeds which are suited to the road cond i­
tions -ris k of crash.
n
Controls and equip­
ment Safety first Vehicle operation
Energy management
Starting ability is optimized
E
nergy management contr ols th e distributi on of elec­
tri cal energy and thus optimizes the availabili ty of elec­
tri cal energ y for star ting the engin e.
If a vehicle with a conventiona l energy system is not dr iven for a long
per io d of time, t he battery is di sch arged by idling cur rent consume rs
(e .g. immob il izer) . In certain c ircumstances it can result in there
being insuffic ien t energy av a ilab le to start t he eng ine .
Inte lligent energy management in your ve hicle hand les the d istribu ­
tion of e lectrical energy . Starting ability is ma rkedly improved and
the l if e of the battery is extended.
Bas ically, energy management consists of
battery d iagnos is, idling
current management
a nd dynamic energy management .
Battery diagnosis
Battery d iagnosis con tinuously dete rmines the st ate o f the batte ry.
Sensors determ ine battery vo ltage, battery current and battery
t empe ra ture. This de termine s the cur rent sta te of cha rge and the
power of the battery.
Idling current management
I d ling current management reduces energy consumption wh ile the
vehicle is s tanding. W ith t he igni tion swi tched off, it con trols the
energy supply to the var io us electrical components. Data from
b att ery diag nosis is considered .
Depend ing on the battery 's state of charge, individual consumers a re
gradually t urned off to p revent excessive discha rge of the battery and
thus main tain start ing capab ility.
Dynamic energy management
Whi le the vehicle is being dr iven , dynamic energy management
dis tributes the energy generated a cco rding to the needs o f th e in di-
Vehicle care Do-it-yourself service Technical data