ABS AUDI Q7 2009 Owner´s Manual

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Safety belts protect
People think it's possible to use the hands to brace the
body in a minor collision. It's simply not true!
Fig . 244 Driv er is
cor rec tly r estrai ned in
a su dden b raking
m an euver
Safety belts used properly can make a big difference. Sa fety belts
help to keep passengers in their seats, gradually reduce energy
levels app lied to the body in an accident, and help prevent the
uncontrolled movement that can cause serious injuries. In addition,
safety be lts reduce the danger of being thrown out of the vehic le .
Safety belts attach passengers to the car and give them the benefit
of being s lowed down more gently or "softly" through the "give" in
the safety belts, crush zones and other safety features engineered
into today's vehicles. By "absorbing" the kinetic energy over a longer period of time, the safety belts make the forces on the body
more "tolerable" and less likely to cause injury .
Altho ugh these examples are based on a frontal co llision, safety
belts can a lso substantially reduce the risk of injury in other kinds
of crashes . So, whether you're on a long trip or just going to the
corner store, a lways buckle up and make sure others do, too. Acci­
dent statistics show that vehicle occupants properly wearing safety
belts have a lower ris k of being injured and a much better chance of
surviving an accident. Properly using safety belts also greatly
increases the abi lity o f the supplementa l airbags to do their job in a
collision . For th is reason , wearing a safety belt is legally required in
most countries including much of the United States and Canada. Although your Audi is equipped with airbags, you sti
ll have to wear
the safety belts provided . Fron t airbags, for example, are activated
only in some frontal collisions . T he front airbags are not activated in
a ll frontal col lisions, in side and rear collisions, in roll ove rs or in
cases where there is not enough dece leration through impact to the
front of the vehicle . The same goes for the other airbag systems in
your Audi . So, always wear your safety belt and make sure every ­
body in your vehic le is properly restrained! •
Important safety instructions about safety
belts
Safety belts must always be co rrectly positioned across
t he strongest bones of your body.
Always wear safety belts as illustrated and described in
th is chapter.
Make s ure tha t your safe ty belts ar e always ready for use
and are not damaged .
& WARNING
Not wearing safety belts or w earing them improperl y increase s
the risk of seriou s per sonal injury and death . S afe ty belt s can work
onl y when used corre ctl y.
• Alway s fa sten your s afety belt s correctl y before dri ving off and
make sure all p assenger s ar e correctly restrain ed.
• For m aximum protect ion , safet y belts must always be po si­
ti oned properly on the body .
• Never strap more th an one person , includi ng sm all children ,
into any belt.
• Never pla ce a s afety belt ove r a child sitting on your lap .
• Alway s keep feet in t he foot well
in front of the seat while the
vehicle is being driven .
~

___ A_ ir_ b_ a-g _ s_y _ s_ t_ e_ m _________________________________________________ _
& WARNING (continued)
• Airbag work most effectively when used with properly worn
safety belts .
• Therefore, always wear your safety belts and make sure that
everybody in your vehicle is properly restrained .
& WARNING
A person on the front passenger seat, especially infants and small
children, will receive serious injuries and can even be killed by
being too close to the airbag when it inflates .
• Although the Advanced Airbag System in your vehicle is
designed to turn off the front passenger airbag if an infant or a
small child is on the front passenger seat, nobody can absolutely
guarantee that deployment under these special conditions is
impossible in all conceivable situations that may happen during
the useful life of your vehicle.
• The Advanced Airbag System can deploy in accordance with
the "low risk" option under the U.S. Federal Standard if a child that
is heavier than the typical one-year old child is on the front
passenger seat and the other conditions for airbag deployment
are met.
• Accident statistics have shown that children are generally safer
in the rear seat area than in the front seating position.
• For their own safety, all children, especially 12 years and
younger, should always ride in the back properly restrained for
their age and size . •
Advanced front airbag system
Your vehicle is equipped with a front Advanced Airbag System in
compliance with United States Federal Motor Vehicle Safety Stan ­
dard 208 as applicable at the time your vehicle was manufactured. The
front Advanced Airbag System supplements the safety belts to
provide additional protection for the driver's and front passenger's
heads and upper bodies in frontal crashes . The airbags inflate only
in frontal impacts when the vehicle deceleration is high enough.
The front Advanced Airbag System for the front seat occupants is
not a substitute for your safety belts . 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 sitting
upright, wearing your safety belt and wearing it properly. This is why
you and your passengers must always be properly restrained, not
just because the law requires you to be.
The Advanced Airbag System in your vehicle has been certified to
meet the "low risk" requirements for 3 and 6 year -old children on the
passenger side and very small adults on the driver side. The low risk
deployment criteria are intended to help reduce the risk of injury
through interaction with the front 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 12 months old and younger who are
restrained on the front passenger seat in child restraints that are
listed in the Standard=>
page 265, "Child restraints and Advanced
Airbags" .
"Suppression" requires the front airbag on the passenger side to be
turned off if:
• a child up to about one year of age is restrained on the front
passenger seat in one of the rear-facing or forward-facing infant
restraints listed in Federal Motor Vehicle Safety Standard 208 with
which the Advanced Airbag System in your vehicle was certified. For
a listing of the child restraints that were used to certify your
vehicle's compliance with the US Safety Standard=>
page 265,
• weight less than a threshold level stored in the control unit is
detected on the front passenger seat. .,

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& WARN ING (continued )
cellular telephones and CB radios , et c.) must be performed by a
qualified technician who has the training and spec ial equipment
ne cessary .
• For any work on the airbag system , we strongly recommend
that you see your author ized Audi dealer or qual ified workshop .
• Never modify the front bumper or parts of the vehicle body.
• Always make sure that the side airbag can inflate without inter ­
ference :
- Never install seat covers or replacement upholstery over the
front seatba cks that have not been spe cific ally approved by
Audi.
- Never use additional seat cushions that cover the areas
where the side airbags inflate.
- Damage to the original seat covers or to the seam in the area
of the side airbag module must always be repaired immedi­
ately by an authorized Audi dealer .
• The airbag system can be activated only once. Afte r an airbag
has inflated , it must be replaced by an authorized Audi dealer or
qualified technician who has the te chnical information , training
and spe cial equipment necessary.
• The airbag sy stem can be deployed only once. After an airbag
has been deployed , it must be repla ced with new repla cement
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 your Audi
Warranty
& Maintenan ce 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
c ircuit interrupter.
- Work on the pyrotechni c circuit interrupter must only be
performed by a qualified dealer -risk of an accident!
& WAR NING (continued )
-If the vehicle or the circuit interrupter is s crapped , all appli­
cable safety precautions must be followed.
ffi For the sake of the environment
Undeployed airbag modules and pretensioners might be c lassified
as Pe rchlorate Material -special handling may apply, see
www .dtsc.ca .gov/hazardouswaste/perc hlo ra te . When t he veh icle or
parts of the restraint system inc luding airbag mod ules and safety
be lts wi th pre tensio ners are sc rapp ed, all ap plicab le laws a nd regu ­
l ations must be observed . Your authorized Audi dealer is fam iliar
wit h these requir ements an d we re co mmen d t hat yo u have your
dea ler perform this service for you. •
Other things that can affect Advanced Airbag
performance
Changing the veh ic le 's su spension system can change the way that
th e Advanced Air bag Syste m performs in a c rash. Fo r example,
using tire-rim combinations not approved by Audi, lowering the
v eh ic le, c hang ing the stif fness of th e suspe nsio n, in cl ud in g the
springs, suspension struts, shoc k absorbers etc . can change the
fo rces that a re m eas ure d b y the air bag senso rs and se nt to the elec ­
tronic control unit. Some suspension changes can, for example,
increa se the fo rce level s measured by the sen so rs and ma ke the
a irbag syste m dep loy in crash es in which it wou ld not dep loy if the
changes ha d not been made . Othe r kinds of change s may red uce
t he fo rce lev els measu red by the se nso rs a nd preve nt the airba g
from deploying when it should.
T he sens ors i n th e safe ty bel t buc kle for th e driver a nd fr ont
passenger seat tell the electronic control modu le if the safety belt is
l a tc h ed or not. I f th e safe ty belt is being used, the fron t airbag wi ll
deploy at a slight ly h igher rate of vehic le dece leration than if the
sa fe ty be lt is n ot b ein g use d. Therefore, i n a partic ular c ollisi on, it i s -.,

Child Safety -
--------------------''---
child is available. In these exceptional situations, the use of a lap
belt is better than perm it t ing the chi ld to remain totally unre ­
strained . But remember: a lap be lt cannot provide the same level of
protection as a proper child restraint or a three -point lap and
shoulder belt if the child is big enough . Also, using a lap belt for
younger child ren, who should be using a chi ld restraint, may vio late
laws in your state o r Province .
Never use a lap belt a lone to res train a chi ld tha t weighs less than
abou t 80 lbs (36 kg) and who is less than 4'9? tall. A lways remember
that children do not have the pronounced pelvic structure required
for the pro per func tion of lap belts . If a lap bel t is only restrain t
system available, then the chi ld's safety absolutely requires that the
lap be lt be fas tened snugly a nd as low as possible arou nd the pe lvis
let a lap belt pass over the chi ld's stomach or abdomen .
& WARNING
Using wrong child rest raints or improperly installed child
restr aint s can cau se seriou s personal injury or death in a crash.
• Fa ilu re to properly ro ute safety belts over a child's body will
c au se severe injuries in a cra sh. The lap belt portion of the three
point belt a s well a s an y lap belt alone mu st always pas s as low a s
possible acros s the pelvi s, never over the stomach or abdomen .
• An improperly worn safet y belt will not pro vide the best protec ­
tion in a cra sh and may cause seriou s personal injury . Always
ma ke sure that children and other vehi cle occupants p rope rly
wear available restraint systems . C arefully follow the instructions
provided by the manufacturers of child re straints . •
Controls and equip­ ment Safety first
Vehicle operation
Installing a child safety seat
Securing a child safety seat using a safety
belt
Sa fety belts for the r ear seats an d the fr ont passenger con
be locked with the convertible locking retractor to prop­
erly secure child safety seats .
The safety belts eme rgency locking retractors for the rear seats
safety belts and for the front passenger's seat safety belt have a
convertible locking ret ractor for child rest raints . The safety belt
must be locked so that belt webbing cannot unreel. T he ret ractor
can be activated to lock the safety be lt and prevent the safety be lt
webbi ng fro m loosen ing up dur ing norma l driving . A child sa fety
seat can on ly be properly installed when the safety belt is locked so
that the child a nd ch ild safety seat will s tay i n place .
A lways remember: Even though your vehic le is equipped with an
Advanced A irbag system, all child ren, espec ially those 12 years and
younger , should a lways ride in the back seat properly restrained for
their age and size.
& WARNING
Improperly installed child safety seat s increase the risk of serious
pe rsonal injury and death i n a collision.
• Always make sure that the safety belt retractor i s locked when
in stalling a child safety seat. An unlocked safety b elt retracto r
cannot hold the child safety seat in pla ce during normal driving or
in a cr ash.
• Always buckle the child safety seat firmly in place even if a
c hild i s not sitting in it . A loo se ch ild safety seat can fly around
durin g a sudden stop or in a collision
• Always make su re that the re ar se at ba ckrest to which the
center rear safety belt is atta ched is se curely latched wh enever
the re ar center safety belt is being u sed to se cur e a child re stra int .
9)1,
Vehicle care Do-it-yourself service Technical data

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Intelligent technology
Notice about data recorded by
vehicle control modu les
Your vehicle is not equipped with an Event Data Recorder (EDR),
installed by some manufacturers for the express purpose of
capturing data for retrieval after an accident or crash event . EDR's
are sometimes called "crash recorders" .
Some state laws restrict the retrieva l or downloading of data stored
by EDR's that were insta lled in a vehicle for the express purpose of
retrieving data after an accident or crash event without the owner's
consent.
Although your vehicle is not equipped with an EDR, it is equipped
with a number of electronic control modules for various vehicle systems such as, for example, engine function, emission control, as
well as for the airbags and safety belts.
These electronic control modules also record vehicle-related data during norma l vehicle operation for diagnost ic and repair purposes .
The recording capacity of the electronic control modules is limited
to data (no sound is recorded) and only a small amount of data is
actually recorded over a very limited period of time and stored when
a system fault or other condition is sensed by a control unit. Some
of the data then stored may relate to 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 .•
Electron ic Stabilizat ion Program (ESP)
General =nformation
The ESP improves the vehicle stability.
Fi g. 2 75 C ente r
co nso le w it h ES P
swi tch
ESP is designed to he lp you maintain vehic le control in situations
where the car approaches the limits of "grip", especia lly when
accelerating and cornering. ESP reduces the risk of skidding and
improves stabil ity under all road conditions .
T he system operates across the entire speed range in combination
with the ABS system. If the Anti-Lock Brake System (ABS) malfunc­
tions, the ESP wil l also shut down .
How th e sys te m w ork s
The Anti -Lock Brake System (ABS) , Electronic Differential Lock (EDU
and the Anti-Slip Regulation System (ASR) are integrated in the e lec­
tronic stabi lization 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 vehic le about its vertical axis, vehicle acce leration in
the fore-and-aft and lateral directions, the brake pressure and the steering angle are al l measured .

•
The direction in which the driver wishes to travel is determined with
t he 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 vehic le starts hydrop laning on a wet
road, ESP will automatically brake the appropriate whee l to correct
the prob lem.
The vehicle is then stab ilized 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 mainly app lied on the wheel that is on
the outside of the curve. In the case of a vehicle that is
understeering
(tendency to sl ide out of the 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 292 . If the Anti-Lock Brake System
(ABS) malfunctions, the ESP will b e out of action as well.
Ac tiva tin g
When you turn on the engine, ESP will automatically be activated
and wil l perform a se lf-tes t. As soon as the test is comp leted, the
system is in norma l operating mode.
Offro ad m ode
ESP should normally be operated in normal mode because this
ensures maximum vehicle stabil ity . If necessary, you can activate
the ESP offroad mode by pressing the button
~ page 288, fig. 275
to obtain maxi mum traction and braking abil ity when dr iving off
paved roads at low speeds . In ESP offroad mode , the ESP indicator
l ight ~
page 19 illuminates and the message E S P Offroad appears
briefly in the display.
The ESP offroad mode can be usefu l in the fo llowing exceptional
s ituat ions when slip or a high ly effective differential locking func ­
tion is desirable. Examples:
• when driv ing with t ire chains,
• when driving in deep snow or on loose ground,
Inte llig ent tec hn olo gy
• when driving on uneven surfaces with the wheels severely
unloaded (articulation), and
• when rocking the vehicle loose after it has become stuck .
When the unusual situation is pas t, you should shift back to the
normal ESP operating mode by pushing the button again. The
message
ESP /A SR on then appears briefly in the display.
Hill d escent contr ol
The hil l descent control is swi tched on in ESP offroad mode . When
s lowly descending steep gradients on loose ground or when the
ax les are a rticulated, h ill descent control provides assistance by
automatically applying the brakes to keep vehicle speed constant.
The vehicle is also rendered easier to steer by se lective distribution
of braking force . Hi ll descent control intervenes when:
• the accelerator pedal is not pressed,
• the veh ic le is trave lling less than 12 mph (20 km/hl,
• a steep gradient is detected,
• whee l behavior indicates loose ground or conditions with poor
adhesion (e .g . also axle articulation).
Hi ll descent control operates both driving forward and in reverse.
Active hill descent contro l is deactivated by pressing the accelerator
pedal until the conditions for activat ion a lready listed are met again .
& WARNING
• The Elect roni c Sta bil izati on Progr am is ne ve rt hele ss subject to
th e law s of phy sics. It is particul arly important to pay attention to
t hi s fa ct on we t and slippery ro ads . It i s therefore i mpo rtant th at
yo u a lw ays adapt your dri vin g to the condition of the ro ad and
traffi c conditions . Do n ot allo w the in cre ased sa fety provided by
the Elect roni c Stabili zation Progr am system to lull you into
ac cepting additional safety r isks.
• Please be aw are th at in ESP offroad mo de, parti cularl y on a
s m ooth and slippery road , the wheel s m ay have an incr eased •
I t •

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& WARNING (continued)
tendency to spin and the vehicle may break away -danger of skid­
ding!
• Stability is limited in the ESP offroad mode. •
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,
accelerate and climb a gradient on surfaces providing poor or
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 292. 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 22. •
Anti-Slip Regulat ion 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 292, 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 wil l also be out of action.
& WARNING
The increased safety afforded by ASR does not mean that you can
take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i ] Tips
To ensure that the ASR works properly, all four wheels must be fitted
with identica l tires. Any differences in rolling radius of the tires can
cause the system to reduce engine power when this is not desired.
See also~
page 359, "New tires and rep lacing tires and wheels". •
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The brakes on today's automobiles are still subject to wear,
depending large ly on operating conditions and driving habits~& .
On vehicles that are either driven mostly in stop-and-go city traffic
or are driven hard, the brake pads shou ld be checked by your autho ­
rized Audi dealer more often than specified in the
Warranty & Main­
tenance booklet.
Failure to have your brake pads inspected can
result in reduced brake performance.
On steep slopes, you shou ld use the braking effect of the engine .
This way, you prevent unnecessary wear on the brake system. If you
must use your brakes, do not hold the brakes down continuously.
Pump the brakes at intervals.
Controls and equip­
ment Safety first Vehicle operation
Intelligent technology
Moisture
or road salt
If you are driving faster than 3 1 mph (50 km/h) and the windshield
wipers are on, the brake pads will briefly touch the brake discs in
regular intervals so as to improve reaction time when braking on
wet surfaces. You, the driver, will not notice anything.
Under certain conditions, for example, when driving through water
or very heavy rain, or even after washing your vehicle, the braking
effect can be reduced due to moisture (or in freezing conditions ice)
on the brake pads. A few careful brake applications sho uld dry off
the brake pads or remove any ice coatings .
The effectiveness of the brakes can be reduced when the vehicle is driven on a salt -covered road and the brakes are not used. Here too,
you should clean off accumulated salt coating from brake discs and
pads with a few carefu l app lications of the brake ~& .
Corrosion
There may be a tendency for dirt to build up on the brake pads and
corrosion to form on the discs if the car is not driven regularly or
only for short trips with litt le use of the brakes.
If the brakes are not used frequently, or if corrosion has formed on
t he discs, it is advisable to clean off the pads and discs by braking
firm ly a few times from a moderately high speed~&.
Faults in the brake system
If you shou ld notice a sudden increase in brake peda l trave l, then
one of the two brake circuits may have failed~& .
Low brake fluid le vel
Malfunctions can occur in the brake system if the brake fluid level is
too low . The brake fluid level is monitored electronically .
Brake lining wear status
Brake lining wear may be checked by visual inspection of the condi ­
tion of the brake pads through the openings in the wheel. If neces­
sary, the wheel may be removed for this inspection
~ page 373,
"Changing a whee l" . ._.
Vehicle care Do-it-yourself service Technical data

___ ln_ t _e_ ll-'"ig ...,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
& WARNING
• You should perform braking maneu vers for the purpose of
cleaning the brake system only if road conditions permit . Other
road u sers mu st not be put at r isk -you may cause an a ccident!
• Before des cending a steep grade, reduce speed and shift trans ­
mission into a lower gear or lower dr iving range . Do not ride the
brakes or hold the pedal down too long or too often. This could
cause the brake s to get hot and diminish braking effi ciency .
• Do not "ride the brakes " by resting your foot on the pedal when
you do not intend to b rake. This may cause the br ake s to ove rheat ,
premature wear and increased stopping distance.
• Under ce rtain climat ic and operating condit ions such as
passing through water , driving in heavy rain or after washing the
vehi cle , the effectiveness of the brakes can be reduced . In winter ,
ice can a ccumulate on the brake pads , linings , discs and drums .
Carefully apply bra kes fo r a test . Brakes will dry and ice coatings
will be cleaned off after a few careful brake appli cations .
• Driving for an extended period of time on salt -co vered roads
without using your brakes can also affect braking effic iency. Clean
off accumulated salt coating from brake dis cs and pads with a few
c areful brake applications .
• If you damage the front spoile r, or if you install a different
spoiler, be sure the air flow to the front brakes is not ob structed.
Otherw ise the brake sy stem could overheat reducing the effective­
ness of the entire brake system .
• Failure of one bra ke cir cuit will impair the braking capability
resulting in an increased stopping distance. Avoid driving the
vehicle and ha ve it towed to the nearest authorized Audi dealer or
qualified workshop . •
Brake booster
T he b rake boost er ad ds extra b ra kin g powe r.
The brake booster works with vacuum pressure which is created
o nly w he n t he e ngine is ru nnin g=> & .
& WARNING
• Never let the vehicle roll to a stop with the engine shut off.
• If the brake booster is not working, for example when towing
your vehicle, or because the brake boo ster has somehow been
damaged , the brake pedal must be pressed considerably harder to
make up for the lack of booster assistance . •
Functioning of A!"lt"-Lock Brake System (ABS)
ABS p revents the wheels from locking up unde r brakin g.
Th e ABS co ntribu tes effect ively to vehicle cont ro l since it preve nts
the whee ls from
locking when the brakes are app lied. This means
t h at the ve hicle rema ins steerable and is less l ikely to s kid.
With ABS you do not need to pump the brake . Just hold the brake
pedal down .
However, do not expec t the A BS to s hor ten bra king d istance u nder
all circumstances. When driving o n grave l or on newly fallen snow
o n t op o f icy sur faces, brak ing d istance may be ev en lon ger, the re­
fore, under these c ircumstances, it is especially important that you
driv e slow ly an d with gre at ca re.
How the ABS system works
An a utomatic c heck is m ade w hen a speed of about 1 2 mph (2 0
km/h) is reached. When this happens, a pumping noise can be
h ea rd.

If an individual wheel begins to rotate too slowly in relation to
vehicle speed and tends to lock, the ABS automatically reduces
brake pressure to prevent that wheel from locking.
This automatic adjustment process will cause a
slight vibration of
the brake pedal and some noises to alert you that vehicle speed
must be adapted to existing road and traffic conditions .
_& WARNING
Although the ABS is very effective, always remember that braking
capability is limited by tire traction. Always adjust your driving
speed according to the road and traffic conditions. Do not let the
extra safety afforded by the ABS tempt you into taking extra risks.
The ABS cannot overcome the laws of physics.
[ i] Tips
• If ABS is not functioning properly , a warning light will come on .
See
=> page 22.
• If a fault occurs in the ABS, the EDL is also not functioning. This
is indicated by the ABS warning light.•
Brake assistant
The brake assistant is designed to achieve the optimum
braking effect.
The brake assistant helps to increase the effective braking power
and thus to achieve
a shorter stopping distance . If the driver
presses the brake pedal very quickly , the brake assistant automati­
cally boosts the braking force to the maximum level, up to the point
where the anti-lock brake function (ABS) intervenes to stop the
wheels from locking. You should then keep th e brake pedal pressed
until the vehicle has braked to the required speed. The brake assis­
tant swi tches its elf off as soon as you release the brake pedal.
Controls and equip­
ment Safety first Vehicle operation
Intelligent technology
Automatic full braking assist
This function allows full braking
in spite of high brake pedal forces
(e.g . when the brakes are severely stressed because the vehicle is
fully loaded) . The driver notices this function through a reduction of
pedal force and increased pedal travel. When the brake pedal is
released, full braking assist switches off again automatically.
If there is an ABS failure, the brake assistant and automatic full
braking assist ar e not available .
The brake assistant will not be operative if there is a malfunction in
the ABS.
_& WARNING
Please remember that the accident risk always increases if you
drive too fast, especially in corners or on a slippery road, or if you
follow the vehicle ahead of you too closely . Increased risk of an
accident cannot be compensated for even by the brake assistant,
so always maintain a safe speed. iJ
Servotronic® -advanced power
steering system
The power steering systems uses the power of the
running engine to allow precise steering with little effort.
The advanced Servotronic ® power steering system senses the road
speed and electronically adjusts power assistance to provide
comfortable and safe steering response exactly matched to the
vehicle speed.
Power steering will not work if the engine is off. As a result, the
s teering whe el will be hard to turn.
The power steering fluid level is checked during the scheduled
maintenance services .
•
Vehicle care Do-it-yourself service Technical data