sensor AUDI A5 COUPE 2010 Service Manual

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PASSENGER AIRBAG OFF light
Fig. 197 Sec tio n fr om
th e i nstrument panel:
PAS SENGER AIR BAG
OFF light
The PASSENGER AIR BAG OFF light is located in the center of the
instrument panel=> fig.
197 .
The PASSENGER AIR BAG OFF light will come on and stay on to tel l
you when the front Advanced Airbag on the passenger side has
been turned off by the electronic contro l unit . Each time you turn on
the ignition, the
PAS SENGER AIR BAG OFF light wi ll flash for a few
seconds and :
• will stay on if the front passenger seat is not occupied,
• will stay on if there is a small chi ld or chi ld restraint on the front
passenger seat ,
• will go out if the front passenger seat is occupied by an adult as
registered by the weight -sensing mat .
The
PASSENGER AIR BAG OFF light must come on and stay on if the
ignition is on and
• a car bed has been installed on the front seat, or
• a rearward-facing child restraint has been installed on the front
passenger seat, or
• a forward-facing child restraint has been insta lled on the front
passenger seat, or
• the weight registered on the front passenger seat is equal to or
less than the combined weight of a typical 1 year-old restrained in one of the rear
-facing or forward-facing infant restraints listed in
Federa l Motor Vehicle Safety Standard 208 with which the Advanced
Airbag System in your vehicle was certified .
I f the front passenger seat is not occupied, the front airbag wil l not
deploy, and the
PASSENGER AIR BAG OFF li ght wi ll stay on. Never
install a rearward -facing child restraint on the front passenger seat,
the safest place for a child in any kind of child restraint is at one o f
the seating posi tions on the rear seat=>
page 190, "Child restraints
o n the front seat -some important things to know" and=>
page 213,
"Chi ld Safety".
If the PASSENGER AIR BAG OFF light comes on when one of the
conditions listed above is met , be sure to check the light regularly
to make certain that the
PASSENGER AIR BAG OFF light stays on
continuously whenever the ignition is on. If the
PASSENGER AIR
BAG OFF
light does not appear and not stay on all the time, stop as
soon as it is safe to do so and
• reactivate the system by turning the ignition off and then turning
it on again;
• remove and reinstal l the child restraint. Make sure that the child
restraint is properly insta lled and that the safety belt for the front
passenger seat has been correctly routed around the child restraint
as described in the child restraint manufacturer's instructions;
• make sure that the convertible locking feature on the safety belt
for the front passenger seat has been activated and that the safety
belt has been pulled tight . The belt must not be loose or have loops
of slack so that the sensor below the safety belt latch on the seat can
do its job =>
page 223.
• make sure that things that may increase the weight of the child
and child safety seat are not being transported on the front
passenger seat;
• make sure that the safety belt tension sensor is not blocked .
Shake the safety belt latch on the front passenger seat back and
forth;
• 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 -.,

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& WARNING (continued )
• Always make sure that the side airbag can inflate without inter­
ference :
- Never install seat covers or replacement upholstery over the
front seatbacks that have not been specifically approved by
Audi.
- Never use additional seat cushions that cover the areas
where the side airbags inflate.
- Damage to the or iginal seat covers or to the seam in the area
of the side airbag module must always be repaired immedi ­
ately by an authorized Audi dealer.
• The airbag system can be activated only once. After an airbag
has inf lated , it must be replaced by an authorized Audi dealer or
qualified technician who has the technical information , training
and special equipment necessary .
• The airbag system can be deployed only once . After an airbag
has been deployed, it must be replaced with new replacement
parts designed and approved especially for your Audi model
version. Replacement of complete airbag systems or airbag
components must be performed by qualified workshops only .
Make sure that any airbag service action is entered in you r 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 reasons with a pyrotechnic circuit interrupter.
-Work on the pyrotechnic circuit interrupter must only be
performed by a qualified dealer -risk of an accident!
- If the vehi cle or the circuit interrupter is scrapped, all appli ­
c able safety precautions must be followed .
Controls and equip­ ment Safety first Vehicle operation
<£' For the sake of the environment
U
ndep loyed airbag modu les a nd p retens ioners mi ght be c lassified
as Perch lorate Mate rial -sp ecia l handling may apply, see
www .dtsc.ca.gov/ haza rdous waste/perc hlorate. W hen the vehicle or
parts of the restraint system including airbag modules safety be lts
w it h pre ten sio ne rs are scrapped, a ll appl ica ble l aws and re gula ­
tions must be observed. Your authorized Audi dealer is familiar with
t hese re qu irements and we rec om men d th at you h ave yo ur dealer
perform this service for you. •
Other things that can affect Advanced Airbag
performance
Changing the vehicle 's suspension system can change the way that
t he Adva nced Airb ag Sys te m per form s in a crash . For e xamp le,
u sing ti re -rim combinations not approved by Audi, lowering the
ve hicle , c hangi ng th e s tif fness of the sus pension , in cluding the
springs, suspension struts, shock absorbers etc. can change the
forc es that are meas ured by the ai rbag se nso rs a nd se nt to t he ele c­
tronic control unit. Some suspension chan ges can, for examp le,
i nc rea se t he for ce le v e ls mea sur ed by the se nso rs and make th e
ai rbag system dep lo y in cras hes in w hich it wou ld not d ep loy if the
changes had not been made . Other kind s of changes may reduce
th e force l eve ls measured by t he sensors and prevent t he airba g
from deploy ing when it should .
Th e sen so rs in the s afet y b elt buckle fo r the driv er and front
passen ger seat tell the electronic control module if the safety belt is
l a tc h e d or n ot. If the safet y b elt i s bei ng use d, th e fr ont ai rb ag will
dep loy at a s lightly hi gher rate of vehic le dece leration than if the
safet y belt is not be ing u sed . The refo re, in a partic ular coll isi on, it i s
poss ible t hat an airbag will not deploy at a s eati ng position where
the safety be lt i s being used b ut wi ll inf late at the pos ition where the
sa fety belt is not being used. I t is im porta nt t hat nothi ng i nterf ere
with the safety belt b uckles so that the sens ors can send the correct
i n fo rm ati on about sa fety belt use to the elect ron ic contro l u nit. .,.
Vehicle care Do-it-yourself service Technical data

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& WARNING
Changing the vehicle's su spension includ ing use of un approved
tire -rim combinations can change Advanced Airbag performance
and increase the ris k of serious personal injury in a crash .
• Never install suspen sion component s that do not have the
same performance chara cteristics as the components or iginally
installed on your vehicle.
• Never use tire-r im comb inations that have not been approved
by Audi.
& WARNING
Items stored between the safety belt bu ckle and the center
c onsole can cause the sensors in the buc kle to send the wrong
information to the electroni c control module and prevent the
Advanced Airbag System from working properly .
• Alway s make sure that nothing can interfere with the safety
belt buckles and that they are not obstructed .
<£> For the sake of the environment
Undeployed airbag modules and pretensioners might be classified
as Perchlora te Mater ial -specia l handling may a pply, see
www.dtsc.ca.gov/hazardouswaste/perchlorate. When the vehicle or
par ts o f the res traint system inclu ding airbag modules sa fe ty be lts
with pretensioners are scrapped, a ll applicable laws and regu la ­
tions mu st be o bserved. You r aut hor ize d Au di d eale r is fami liar with
these requirements and we recommend that you have your dea ler
perform this service for you. •
Knee airbags
Applies to vehicles: with knee air bags
Description of knee airbags
The airbag system c an provide supplemental pr otection
to pr operly res traine d fron t sea t occupan ts .
....
! 00 m
F ig . 19 8 Drive r's kne e
airba g
The knee a irbag for the driver is located in the instrument panel
underneath the stee ring wheel => fig. 19 8, the knee air bag for the
passeng er is at about the same height in th e instrument pane l
underneath the glove compartment .
Th e kn ee ai rbag offers addi tional pr otec tion to the d river's a nd
passenger 's knees and upper and lower thigh a reas as a supple ­
me nt to t he sa fety be lts .
I f the front airbags deploy , th e knee airbags also deploy in frontal
collisions above a certain severity=>
page 197, "M ore important
things to know about front airbags".
Besides their normal safety function, safety belts wor k to help keep
th e dri ver o r fr on t passeng er in pos itio n in case of a fro ntal col lis io n
so that the airbags can provide protection .
T he airbag system is not a substitute for your safety belt . Rathe r, it
is part of the overall occupant restra int system in your vehicle .
A lwa ys remember that the airbag system can only help to protect .,,_

Side airbags
Description of side airbags
The airbag system can provide supplemental protecti on
to properly rest rained occupants.
Fi g. 200 Si de a ir b ag
lo ca tio n in th e driv er's
seat
The side airbags are located in the sides of the front seat backrests
=> fig. 200. They are identified by the word "AIRBAG".
The side a irbag sy stem ba sic ally con sis ts of :
• the electronic contro l 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 moni tored electronically to make cer tain that
it is functioning 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).
T he 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 colli­
sion. The airbag deploys only in side impacts and on ly when the
vehicle acceleration registered by the control unit is high enough. If
t his rate is below the reference va lue programmed into the contro l
unit, the side airbags will not be triggered, even though the car may
Safety first
Airbag sy ste m
be badly damaged as a result of the collision. It is not possible to
define an airbag triggering range tha t wi ll cover every possible
ang le of impact, since the circumstances wi ll 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 208, "Important safety
instructions on the side airbag system".
Aside from their norma l safety function, safety belts work to help
keep the driver or front passenger in posi tion in the event o f a side
collision so that the side airbags can provide protection.
The airbag system is
not a substitute for your safety belt. Rathe r, it
is part of the overall occupant restraint system in your vehicle.
Always remember that the side airbag system can only he lp to
protect you if you are wearing your safety belt and wear ing it prop­
erly. This is another reason why you should always wear your safety
belts, not just because the law requires you to do so=>
page 179,
"General notes".
It is important to remember that while the supp lementa l side airbag
system is designed to reduce the likelihood of serious injuries, other
inju ries, for e xample, swell ing, bruising, and minor abras ions can
also be associated with deployed side airbags. Remember too, side
airbags will deploy only once and on ly in certain kinds of accidents
- your safety be lts are a lways there to offer protection.
Vehicle damage, repair costs or even the lack of vehicle damage are not necessarily an indication of ove r-sensitive or fa iled airbag acti­
vation. In some collisions, both front and side airbags may inflate.
Remember too, tha t airbags w ill deploy only once and on ly in
certain kinds of collisions -your safety belts are always there to
offer protection 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 accele ration measured by the sens or
is too low
~
Vehicle care I I irechnical 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 inter ­
ference .
- Never install seat covers or replacement upholstery over the
front seat backs that have not been specifically approved by
Audi.
- Never use additional seat cushions that cover the areas
where the side airbags deploy.
- Damage to the original seat covers or to the seam in the area
of the side airbag module must always be repaired immedi­
ately by an authorized Audi dealer .
• Objects between you and the airbag can increase the risk of
injury in an accident by interfering with the way the airbag unfolds
or by being pushed into you as the airbag inflates .
- Never place or attach accessories or other objects (such as
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 .
Controls and equip­ ment Safety first
Vehicle operation
& WARNING (continued)
• 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.I to the original seat covers
or to the seam in the area of the side airbag module must always
be repaired immediately by an authorized Audi dealer .
• If children are seated improperly, their risk of injury increases
in the case of an accident
~ page 213 , "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 p roperly restrained occup ants.
Fig. 202 Si de cu rtai n
sys te m , d riv er' s s ide:
s ide curtai n airb ag
l oca tio n
The side curtain airbags are located on both sides of the interior
above the front and rear side windows=:> fig . 202 . They are identi ­
fied by the word "AIRBAG" on the windshield frame and the center
roof pillar.
The side curtain airbag system supplements the sa fety be lts and
can help to reduce the risk of injury for occupants' heads and upper
t orso on the side of the vehicle that is struck in a side collision . The
side curtain airbag inflates only in side impacts and on ly when the
vehic le acceleration 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 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 circums tances will vary considerab ly
between one col lision and another. Important factors include, for
examp le, the nature (hard or soft) of the impacting object, the angle
of impact, vehicle speed, etc.=:>
page 211, "How side curtain airbags
work" . Aside from their normal safety function, safety belts work
to help
keep the driver or fron t passenger in position in the event of a colli ­
sion so that the side curtain airbags can provide protection.
The airbag system is not a substitute for your safety belt . Rather, it
is part of the overall occupant restraint system in your vehicle .
Always remember that the airbag system can only help to protect
you if you are wearing your safety belt and wearing it properly. This
is another reason why you should always wear your safety belts, not
just because the law requires you to do so=:>
page 179, "General
notes".
I t is important to remember that while the s ide curtain airbag
system is designed to he lp reduce the like lihood of ser ious injuries,
other injuries, for examp le, swelling, bruising, and minor ab rasions
can a lso be associated wi th t hese airbags. Remember too, these
airbags will deploy only once and only in certain kinds of accidents
- your safety belts are a lways there to offer protection.
The sid e curtain airbag system b asically con sist s of :
• The electronic control module and externa l s ide impact sensors
• The side curtain airbags above the front and rear side windows
• The airbag indicator light in the instrument panel
The airbag system is monitored e lectronically to make certain it is
funct ioning proper ly at all t imes. Each time you turn on the ignition,
the airbag system indicator light will come on for a few seconds (self diagnostics) .
The sid e curtain airb ag i s not activated:
• if the ignition is turned off,
• in side collisions when the acceleratio n measured by the sensor
is too low,
• in front -end co llisions,
• in rear -end collisions.

-Child Safety ------=---------------------------------
& WAR NIN G (co ntinued )
• Alw ays inst all r ear ward-f acing child safet y sea ts on the r ear
s eat.
• If you must in stall a r earward facing child saf ety seat on the
front p assenger seat in e xcept ion al circum sta nce s and the
PASSENGER AIR BAG OFF light doe s not come on and stay on ,
imm edi atel y ins ta ll the re arw ard -fa cin g child safety seat in a re ar
s eating po sit ion and have the airb ag s ystem inspe cted immedi­
a tely by your autho rized Audi dealer .
& WARNING
If, in e xce ptional cir cum sta nces, you mu st in stall a fo rward-fa cing
c hild restraint on the front p asseng er's seat :
• Alway s m ake s ure the forw ard -fa cing seat h as been de signed
and cert ified by its manufacturer for use on a front seat with a
passenger front and side airbag.
• Alway s follow the m anufacturer's instructi on s provided with
the child s afety seat or carrier .
• Alway s move the p assenger seat into it s rearmo st position in
the seat's fo re and aft adju stment range , as far a way from the
airbag a s po ssible b efore in stalling the child restraint. The ba ck­
rest must be adjusted t o an up rig ht position .
• Alway s m ake sure that the PA SSENG ER AIR BAG OFF light
c ome s on and stays on all the time whenever the ign iti on is
switched on. •
Advanced front airbag system and children
Your vehicle is equipped with a front "Advanced Airbag System" in
compliance with United States Federa l Motor Vehicle Safety Stan ­
dard (FMVSS) 208 as applicable at the time your vehicle was manu ­
factured . T
he Advanced Airbag system in your vehicle has been certified to
meet the " low -risk" requiremen ts for 3 -and 6 -year o ld children on
the passenger side and smal l adults on the driver side . The low risk
deployment criteria are intended to reduce the risk of injury through
interaction with the airbag that can occur , for example, by being too
close to the steering wheel and instrument panel when the airbag
inflates. In addition, the system has been certified to comply with
the "suppression" requirements of the Safety Standard, to turn off
the front airbag for infants up to 12 months who are restrained on
the front passenger seat in child restraints that are listed in the
S tandard.
Even though your vehicle is equipped with an Advanced Airbag
system, all ch ildren, especially those 12 years and younge r, should
always ride in the back seat properly restrained for their age and
size . The airbag on the passenger side makes the front seat a poten ­
tially dangerous p lace for a child to ride. The front seat is not the
safest p lace for a child in a forward -facing child safety seat . It can be
a very dangerous p lace for an infant or a larger ch ild in a rearward­
facing seat. •
Advanced Airbags and the weight-sensing
mat in the front seat
The Advanced Airbag System in your vehicle detects the presence
of an infant or child in a chi ld restraint on the front passenger seat
using the weight -sensing mat in the seat cushion and the sensor
below the safety belt latch on the front passenger seat that
measures the tension on the safety belt.
The weight -sensing mat measures total weight of the chi ld and the
child safety seat and a child blanket on the front passenger seat . The
weight on the front passenger seat is related to the design of the
child restraint and its "footprint", the size and shape of the bottom
of the child restraint as it sits on the seat . The weight of a child
restraint and its "footprint" vary for different kinds of child ..,.

-------------------------------------------~C::._! h~ i~ ld ~ S~ a~ f~e :_!t tY ~--
restraints 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
child restraints that the NHTSA has specified in the Safety Standard
together with the weight ranges of typ ical 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 child, the Advanced Airbag
System compares the weight measured by the weight sensing mat
with the information stored in the electronic control unit.
The electronic control unit also 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, 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 chi ld restraint is properly
installed at one of the rear seating positions. If in exceptiona l
circumstances you must use it on the front passenger seat, carefully
read all of the information on child 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
th e
PASSENGER AIR BAG OFF light .
Controls and equip­
ment Safety first Vehicle operation
Many
types and models of child restraints have been available over
the years, new mode ls are introduced regularly incorporating new
and improved designs and older mode ls are taken out of produc­
tion. Child restraints are not standardized . Child restraints of the
same type typically have different weights and sizes and different
'footprints,' the size and shape of the bottom of the chi ld restraint
that sits on the seat, when they are installed on a vehicle sea t. These
differences make it virtual ly impossible to certify comp liance with
the requirements for advanced airbags with each and every child
restraint that has ever been sold in the past or will be sold over the
course of the usefu l life of your vehic le.
For this reason, the United States National Highway Traffic Safety
Administration has pub lished a list of specific type, makes and
models of child restraints that must be used to certify compliance
of the Advanced Airbag System in your vehicle with the suppression
requirements of Federal Motor Vehicle Safety Standard 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 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 lnfant8457
Vehicle care Do-it-yourself service Technical data

The system operates across the entire speed range in combination
with the ABS system. If the Anti -Lock Brake System (ABS) ma lfunc­
tions, the ESP wil l also shut down .
How the system works
The Anti -Lock Brake System (ABS), Electronic Differential Lock (EDU
and the Anti -Slip Regulation System (ASR) are integrated in the elec­
tronic stabilization program. In addition to the data provided by
th ese functions, the ESP control unit requires additional measure ­
ment data provided by high performance sensors . The rotational
speed of the vehicle about its vertica l axis, vehicle acceleration in
the fore-and-aft and lateral directions , the brake pressure, and the
steering angle are all measured.
The direction in which the driver wishes to travel is determined with
the aid of the steering angle and vehicle 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 laning on a wet
road, ESP will automatically brake the appropriate whee l to correct
the prob lem.
The vehicle is then stabi lized by the forces acting on the whee l
during braking. If the vehicle is
oversteering (the vehicle turns too
sharply and the rear wheels slide toward th e ou tside of a curve), the
brakes are main ly app lied 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
additional ly on the other wheels. An acoustic signal indicates when
ESP brake app lication cuts in=>&.
T he system operates across the entire speed range in combination
with the ABS system =>
page 238. 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 automatica lly be activated
and will perform a se lf-test. As soon as the test is comp leted, the
system is in norma l operating mode.
Controls and equip­
ment Safety first Vehicle operation
Intelligent technology
You
can activate a deactivated ESP or deactivated ESP/ASR if
required by pressing the::::>
page 234, fig. 215 ::::> page 234, fig. 214
button . When they are activated, the message
ESP /ASR on appears
briefly in the display .
Deactivating
The ESP should normally be activated al l the time. If necessary, you
can deactivate Anti -Slip Regu lation (ASR) or the Electronic Stabiliza­
tion Program (ESP) by pressing the button=>
page 234, fig. 215.
• Deactivating ASR: Tap the button . In certain exceptional situa­
tions (e .g. driving with tire chains), the Anti-Slip Regulation (ASR)
can be deactivated =>
page 236. The message ASR off appears in the
display as we ll.
• Deact ivating ESP/ASR Press the button for more than 3 seconds.
With the ESP/ASR deactivated, the indicator light comes on, see
=>
page 13. The message ESP switched off appears in the disp lay as
we ll.
& 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 Elec­
tronic 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 (EDU helps the car to start moving,
acc elerate and c limb a gradient on surfaces providing poor or
Vehicle care Do-it-yourself service Technical data

ll}JI Intelligent technology
---""'------------ ....::....:...:~---------------------------
almost no grip. Without EDL, this would be difficult, if not impos­
sible.
How the system works
The EDL operates automatically. It monitors the rotational speed of
wheels with the help of the ABS sensors=:,
page 238 . If a noticeable
slip is detected at the wheels (e.g. on slippery ground on one side),
the spinning 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).
Noises from the brake system signal that wheel spin is being
controlled.
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, apply
plenty of throttle until the car starts to move.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads on this wheel, the EDL cuts out tempo­ rarily. The vehicle remains operational and behaves in the same way
as a vehicle 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
can 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 15. •
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 spinning by adjusting the
engine power to match the amount of grip available from the road
surface.
How the system works
ASR performs automatically , i.e. without the driver's intervention .
With the aid of the ABS sensors=:,
page 238, ASR monitors the
speed of the driven wheels. If the wheels start to spin, engine torque
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 should
occur in the ABS, the ASR will also be out of action.
Activating
The ESP is automatically activated when the engine is started and it
performs a self-test . You can activate a deactivated ASR if required
by pressing the=:,
page 234, fig. 215 button. When it is activated,
the message
ESP/ASR on appears briefly in the display.
Deactivating
You can deactivate the ASR if required by pressing the button (for
less than 3 seconds) =:,
page 234, fig. 215. With the ASR deactivated,
the ESP check light comes on, see=:,
page 13. The message ASR off ._