wheel AUDI Q7 2013 Owner´s Manual

What happens to occupants not wearing
safety belts?
In crashes unbelted occupants cannot stop themselves from flying forward and being in­
jured or killed. Always wear your safety belts!
Fig. 201 A driver not wearing a safety belt is violently
thrown forward
Fig. 202 A rear p assenger not wearin g a safety belt
will fly forwar d an d st rike the driver
Unbelted occupants are not able to resist the
tremendous forces of impact by holding tight
or brac ing themselves. W ithout the benefit of
safety restraint systems, the unrestrained oc­
cupant will slam vio lent ly into the steering
wheel, instrument panel, windshield , or what­
ever else is in the way ¢
fig. 201. This impact
with the vehicle interior has all the energy
they had just before the crash.
Never rely on airbags alone for protection.
Even when they deploy, airbags provide only
additional protection. Airbags are not sup­ posed to deploy in all kinds of accidents. Al­
though your Audi is equipped with airbags, all
vehicle occupants, including the driver , must
wear safety belts correctly in order to mini­
mize the risk of severe injury or death in a
crash.
Remember too, that airbags will deploy only
once and that your safety belts are always
Safety belts 177
there to offer protection in those accidents in
which airbags are not supposed to deploy or
when they have already deployed. Unbelted
occupants can a lso be thrown out of the vehi­
cle where even more severe or fatal injuries
can occur .
It is also important for the rear passengers to
wear safety belts correctly . Unbelted passen­
gers in the rear seats endanger not only them­
selves but also the driver and other passen ­
gers ¢
fig. 202. In a frontal coll ision they will
be thrown forward violently, where they can
hit and injure the driver and/or front seat pas­
senger.
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. 203 D river is correctly rest ra in ed in a sudde n brak­
ing maneuver
Safety belts used properly can make a big dif­
ference. Safety belts help to keep passengers
in their seats, gradua lly reduce energy levels
applied to the body in an accident, and help
prevent the uncontrolled movement that can
cause serious injuries. In addition, safety belts
reduce the danger of being thrown out of the
vehicle.
Safety belts attach passengers to the car and
give them the benefit of being slowed 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
liJl,

184 Airbag sys tem
Airbag system
Important things to know
Importance of wearing safety belts and
sitting properly
Airbags are only supplemental restraints. For
airbags to do their job , occupants must al­
ways properly wear their safety belts and be
in a proper seating position.
F or your safety and the safety of your passen­
gers, before driving off, a lways:
• Adjust the dr iver's seat and steering wheel
properly ¢
page 166,
• Adjust the front passenger's seat properly
r=;page 72 ,
• Wear safety be lts properly
r=; page 178,
• Always properly use the proper child re-
stra int to protect children¢
page 205.
In a collision, airbags must inflate within the
blink of an eye and with considerable force .
The supplementa l airbags can cause injuries if
the dr iver or the front seat passenger is not
seated properly . Therefore in order to he lp the
a irbag to do its job, it is important, both as a
d river and as a passenge r to sit properly at all
times.
By keeping room between your body and the
steering wheel and the front of the passenger
compartment, the airbag ca n inflate fully and
comp letely and provide supp lemental p rotec­
tion in ce rtain frontal collisions¢
page 166,
Proper occupant seating positions .
For detai ls
on the operat ion of the seat adjustment con­
trols ¢
page 72.
I t's especially important that children a re
properly restrained ¢
page 205.
There is a lot that the driver and the passen­
gers can and must do to help the individua l
safety features ins talled in your A udi work to­
gether as a system.
Prope r seat ing pos ition is important so that
the front airbag on the driver s ide can do i ts
job. If yo u have a physical impa irment or con- dition that prevents you from sitting properly
on the driver seat with the safety belt properly
fastened and reaching the peda ls , or if you
have concerns with regard to the function or
operation of the Advanced Airbag System,
please contact your author ized Audi dealer or
qualified workshop, or call Audi Customer Re­
lations at 1-800-822-2834 for poss ible modi­
fica tions to your ve hicle.
When the airbag system deploys, a gas gener ­
ator will f il l the a irbags, break open t he pad­
ded cove rs, and i nflate between the steer ing
whee l and the dr iver and between the instru­
ment pane l and the front passenger. The a ir­
bags will deflate immediately after dep loy­
ment so tha t the front occupants can see
t h ro ugh the windshie ld again witho ut inter­
ruption .
All of th is takes p lace in the b link o f an eye, so
fast that many peop le don't even realize tha t
the airbags have dep loyed. The airbags a lso
inflate with a great dea l of force and nothing
shou ld be in their way when they deploy.
Front a irbags in combination with properly
wor n safety belts slow down and lim it the oc ­
cupant's forward movement . T ogether they
help to prevent the drive r and front seat pas­
senger from hitting pa rts of the inside o f th e
vehicle while reducing the forces acting on the
occupant dur ing the crash . In this way they
help to reduce the risk of injury to the head
and upper body in the crash. A irbags do not
protect the arms or the lower parts of the
body.
Both front airbags wi ll not inflate in all fronta l
collisions . The t riggering of the airbag system
depends on the vehicle dece lerat ion rate
ca used by the co llision and registered by the
electron ic control unit. If th is rate is below
the reference value programmed into the con ­
t rol unit , the airbags will not be trigge red,
even though the car may be badly damaged as
a res ult of the co llision . Ve hicl e damage, re­
pair costs o r even the lack of ve hicle damage
is not necessari ly an indication of whe ther an
airbag shou ld inflate or not .
IJll-

Since the circums tances will vary considerab ly
between one collision and another , it is not
possible to define a range of veh icle speeds
that will cover every possible k ind and angle
of impact t hat w ill always t rig ger the a irbags .
Important factors include, for example, the
nature (hard or so ft) of the object which the
car h its, the ang le of impact, vehicle speed,
etc. The front airbags will a lso not inflate in
side or rear collisions, or in ro ll-overs .
Alw ays rememb er: Airbags will deploy only
once, and only in certa in kinds of co llisions.
Your safety belts are always there to offe r pro­
tect ion in those s ituations in which airbags
are not supposed to deploy, or when they have
a lready deployed ; for example , when your ve­
hicle strikes or is struck by another vehicle af­
ter the first co llision .
This is just one of the reasons why an a irbag is
a supp lementary restraint and is not a s ubsti ­
tute for a safety belt . The airbag system
works most effectively when used with the
safety belts. Therefore, always properly wear
your safety belts¢
page 175.
A WARNING
Sitting too close to the steer ing whee l or
instrument panel will dec rease the effec­
tiveness of the airbags and will inc rease
the risk of pe rsonal injury in a co llision .
- Never sit closer than 10 inches (2S cm)
to the stee ring wheel or instr ument pan­
el.
- If you cannot sit more than 10 inches
( 2 5 cm) from the steer ing whee l, investi­
ga te whethe r adaptive equipment may
be available to help you reach the pedals
and increase your seating distance from
the steering wheel.
- If you are unrestrained, lean ing forward,
sitting sideways or out of position in any
way, yo ur risk of inj ury is much higher.
- You w ill also receive serio us injuries and
cou ld even be killed if you are up against
the a irbag or too close to it when it in­
flates -even with an Advanced Airbag.
A irbag system 185
-To reduce the risk of injury when an air­
bag inflates, always wear safety belts
properly ¢
page 179, Safety belts.
-Always make certain that ch ild ren age 12
or younger a lways ride in the rear seat. If
children are not properly restrained, they may be severe ly inju red or killed when an
airbag inf lates .
- Never let ch ildren ride unrestra ined or
improperly restrained in the vehicle. Ad­
just the front seats prope rly .
- Never ride with the back rest reclined .
- Always sit as far as possible from the
steer ing whee l or the instrument pane l
¢page 166.
-Always sit upright with your back against
the backrest of your seat .
- Never p lace your feet on the instrument
panel or on the seat. Always keep both
feet on the f loor in front of the seat to
he lp preven t serio us in ju ries to the legs
and h ips if the airbag infla tes.
- Never recline the front passenger 's seat
to transport objects . Items can a lso
move into the area of the s ide a irbag or
the front a irbag du ring bra king or in a
sud den maneuve r. Obje cts near the air ­
bags can become projectiles and cause
in jur y when an airbag inflates.
A WARNING
Airbags that have de ployed in a crash must
be replaced.
- Use on ly orig inal equipment airbags ap­
proved by Aud i an d installed by a trained
technician who has the necessary too ls
and d iagnost ic equipment to properly re­
place any airbag in your vehicle and as­
sure system effectiveness in a crash .
- Never perm it salvaged or recycled air­
bags to be installed in your vehicle . •
•

188 Airbag system
prevent them from providing any
protection.
- An improperly installed child restraint
can interfere with the airbag as it de­
ploys and serious ly injure or even kill the
child -even with an Advanced Airbag
System .
- Always carefully follow the manufactur­
er's instructions provided with the child
safety seat or carrier.
- Never place additional items on the seat
that can increase the total weight regis­
tered by the weight-se nsing mat and can
cause injury in a crash.
Front airbags
Description of front airbags
The airbag system can provide supplemental
protection to properly restrained front seat
occupants.
Fig. 2 09 Locat ion of dr ive r air bag : in stee ring wheel
Fig. 2 10 Locat ion of front passenger's a irbag: in the in­
st rument panel
Your veh icle is equipped with an "Advanced
A irbag System" in complia nce w ith United
States Federal Motor Vehicle Safety Standard
( FM VSS) 208 as app licab le at the time your
veh icle was manufactured. The safety belts f
or the seats have "pretensioners" that help
to take slack out of t he belt system . The pre­
tens ioners are also act ivated by the electronic
control unit for the airbag system.
T he front safety be lts also have load limiters
to help reduce the forces applied to the body
i n a crash .
T he airbag for the drive r is in the stee ring
whee l hub ¢
fig. 209 and the airbag for the
front passenger is in the instr ument panel
~ fig. 210 . The general locat ion of the a irbags
is marked "AIRBAG".
T here is a lot you nee d to know about the ai r­
bags in your vehicle . We urge you to read the
detailed information about airbags, safety
belts and child safety in this and the other
chapters that make up the owner's literature.
P lease be sure to heed the WARNINGS -they
are extremely importa nt for your safety and
the safety of you r passengers, especially in­
fants and small chi ldren.
_&. WARNING
Neve r rely on airbags alo ne for p rotection.
- E ven w hen they deploy, airbags provide
only supplement al pro tectio n.
- Airbag work most effect ive ly when used
with p roperly wor n safety bel ts.
- Therefore, always wea r you r safety belts
a nd make sure tha t eve rybody in your ve­
h icle is properly res trained.
_&. WARNING
A pe rso n on the fron t passenger seat, es­
pe cial ly infa nts and sm all ch ildren, w ill re­
ceive serio us inju ries and can even be kil-
l ed by being too close to the airbag when
it inflates .
- A lthough t he Advanced Airbag System in
your veh icle is des igned to tur n off the
front passenge r airbag if an infant or a
small child is on the front passenger
seat, nobody can absolutely guarantee
-
that deployme nt under these special ..,

conditions is impossible in all conceiva­
ble s ituations that may happen during
the useful life of your vehicle.
- The Advanced A irbag System can deploy
in accordance with the "low risk" opt ion
under the U.S. Federa l Standard if a child
that is heavier than the typical one-year
old child is on the front passenger seat
and the other cond itions for airbag de­
ployment are met.
- Acc ident statist ics have shown that chil­
dre n are generally safe r in the rea r seat
area than in the front se ating posit io n.
- For their own safety , all children, espe­
ci ally 1 2 yea rs and younger, sho uld al­
w ays ride in the ba ck p roperly restrained
f or their age and size .
Advanced front airbag system
Your vehicle is equipped w it h a front Advanced
Ai rbag System in compl iance with United
States Federal Motor Vehicle Safety Standard
208 as applicable at the time your vehicle was
manufactured.
The front Advanced Airbag System supp le ­
ments the safety belts to provide addit iona l
protection for the driver's and front passeng­
er's heads and upper bodies in frontal crashes.
The airbags inflate only in frontal impacts
when the vehicle decele rat io n is high enough .
The front Advanced Airbag System for the
fro nt seat occupants is not a substitute for
your safety belts . Rather, it is part of the over­
all occupant rest raint system in your veh icle .
A lways remember that the airbag system can
only help to pro te ct you, if you a re s itting up­
right, wearing yo ur safe ty be lt and wearing i t
p roperly. This is why you and yo ur passenge rs
must always be properly restrained, not just
beca use the law requires you to be.
The Advanced Airbag System in your veh icle
h as been cer tified to meet the " low r is k" re ­
q uir ements for 3 and 6 year -o ld children on
the passenger side and very small adu lts on
the dr iver side. The low risk dep loyment crite­
ria are intended to he lp red uce the risk of in-
A irbag system 189
jury through interaction with the front ai rbag
that can occur, for examp le, by being too
close to the steering wheel and instr ument
panel when the airbag inflates.
In add ition, the system has been certi fied to
comply with the "s uppression" requirements
of the Sa fety Standa rd, 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 207, Child restraints and
Advanced Airbags .
"Suppression" requires the front a irbag on the
passenger s ide to be turned off if:
- a child up to abo ut one year o f age is re ­
strained on the front passenger seat in one
of the rear-fac ing or fo rward-facing infant
restrai nts listed in Federal Motor Vehicle
Safety Standa rd 208 with wh ich the Ad­
vanced Ai rbag System in your ve hicl e was
cert ified. Fo r a listing of the chi ld res traints
t h at were used to certify you r vehi cle's com­
pliance w it h t he US Sa fe ty Standard
~page 207,
-weigh t less than a thres ho ld level stored in
the control unit is de tected on the fron t pas ­
senger seat .
When a person is dete cted on t he front pas ­
senger se at, weigh ing more than the tota l
weight of a chi ld tha t is about 1 year old re ­
stra ined in one of the rear-facing or forward ­
facing infant restraints ( listed in Federal Mo­
tor Vehicle Safety Standard 208 w ith which
the Advanced Airbag System in you r vehicle
was certified), the front airbag on the passen­ ger side may or may not de ploy.
The
PASSENGER AIR BAG OFF light comes on
whe n the electro nic contro l unit detects a to­
ta l we ight on the front passe nger seat that re­
quires the front airbag to be tu rned off . If the
PASSENGER AIR BAG OFF light does no t
come on, the front ai rbag on t he passe nger
s ide has not been turned off by the cont ro l
u ni t an d can dep loy if t he con trol un it senses
an impact that meets the cond itions stored i n
its memory . ..,. •
•

-Always make sure the forward-facing
seat has been des igned and certified by
its manufacturer for use on a front seat
with a passenger front and side airbag .
- Never put the forward-facing child re­
straint up aga inst or very near the instru­
ment panel.
- Always move the passenger seat into its
rearmost position in the seat's fore and
aft adjustment range, as far away from
the a irbag as poss ible, before insta lling
the fo rward-facing child restraint . The
b ackres t m ust be adjus ted to an upr ight
posit ion.
- Make su re that the
PASSENGER AIR BAG
OFF
light comes on and s tays on all the
t ime whenever the ignition is switched
on .
Advanced Airbag System components
The front passenger seat in your vehicle has a
l ot of very important parts of the Advanced
Airbag System in it. These parts include the
weight-sens ing mat, sensors, wiring, brack­
ets, and more . The function of the system in
the front passenger seat is checked by the
e lectronic control un it when the ignit ion is on .
The control un it mon itors the Advanced Air ­
bag Sys tem and turn s the a irbag in dica tor
light on when a ma lfunction in t he system
components is detected . The function of the
airbag indicator light is described in greater
deta il below. Because the front passenger
seat contains important parts of the Ad­
vanced A irbag System, you must take care to
prevent it from being damaged . Damage to
the seat may p revent the Advanced A irbag for
the front passenger seat from doing its job in
a crash .
The front Advanced Airb ag System
consists of the following:
- Crash sensors in the front of the veh icle that
measu re ve hicle accelera tion/decele ra ti on
to provide inform ation to the Advanced Air ­
bag System about the severity of the crash.
A irbag system 19 1
-An elect ron ic cont ro l unit, with integrated
crash sensors for front and side impacts .
The control un it "decides" whether to f ire
the front a irbags based on the informat ion
received from the crash sensors. The control
unit also "decides" whether the safety belt
prete nsioners shou ld be act iva ted.
- An Advanced A irbag w it h gas generator for
the driver inside the steering wheel hub .
- An Advanced A irbag w ith gas generator in­
side the instrument pa nel for the front pas­
senge r.
- A weight-sensing mat under the upholstery
padding of the front passenge r seat cushion
that measures the to tal weight o n the seat.
The informat ion reg iste red is sent continu­
ously to the elect ronic con trol u nit to regu­
la te deployment of the front Adv anced Air­
bag on the passenger side .
- An airbag moni tori ng sys tem and ind ic a tor
light in the instr ument cluster
q page 195.
- The PASSENGER AIR BAG OFF ligh t comes
on and st ays on in the cen ter o f th e instr u­
ment panel
q page 195, fig . 212 and tells
you whe n the front Advanced Airbag on the
passenger side has been tu rned
off .
-A sensor below the safety be lt latch fo r the
front seat passenger to measure the tension on the safety be lt . The tension on the safety
be lt and the weight registered by the
weight-sensing mat he lp the control unit
"decide" whether the front a irbag for the
front passenge r seat should be turned
off or
not
q pag e 186, Child restraints on the
front seat -some important things to
know.
- A senso r in the safety belt latch fo r the d riv­
er a nd fo r the fro nt sea t passenger tha t
senses w hethe r that safe ty belt is latched or
no t and transmi ts this informa tion to the
electronic control unit.
.&_ WARNING
Damage to the front passenger seat can
prevent the front airbag from work ing
properly.
-
•
•

198 Airbag system
(D Tips
If the weight-sensing mat in the front pas­
senger seat detects an empty seat, the
front airbag on the passenger side will be turned off, and the
PASSENGER AIR BAG
OFF
light will stay on.
Repair, care and disposal of the airbags
Parts of the airbag system are installed at
many different places on your Audi . Installing,
removing, servicing or repairing a part in an
area of the vehicle can damage a part of an
airbag system and prevent that system from
working p roperly in a collision.
There are some important things you have to know to make sure that the effectiveness of
the system will not be impaired and that dis­
carded components do not cause injury or pol­
lute the environment.
A WARNING
Improper care, servicing and repair proce­
dures can increase the risk of personal in­
jury and death by preventing an airbag from deploying when needed or deploying
an airbag unexpectedly:
- Never cover, obstruct, or change the steering wheel horn pad or airbag cover
or the instrument panel or modify them
in any way .
- Never attach any objects such as cu­
pholders or telephone mountings to the
surfaces covering the airbag units.
- For cleaning the horn pad or instrument
panel, use only a soft, dry cloth or one
moistened with plain water. Solvents or
cleaners could damage the airbag cover
or change the stiffness or strength of the material so that the airbag cannot de­
ploy and protect properly.
- Never repair , adjust, or change any parts
of the airbag system.
- All work on the steering wheel, instru­
ment panel, front seats or electrical sys­
tem (including the installation of audio
equipment, cellular telephones and CB radios, etc.) must be performed by a
qualified technician who has the training
and special equipment necessary.
- For any work on the airbag system, we
strongly recommend that you see your
authorized Audi dealer or qualified work­
shop.
- Never modify the front bumper or parts
of the vehicle body.
- Always make sure that the side airbag
can inflate without interference:
- Never install seat covers or replace­
ment 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
inflate.
- Damage to the original seat covers or
to the seam in the area of the side air­
bag module must always be repaired
immediately by an authorized Audi
dealer. - The airbag system 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 system can be deployed only once . After an airbag has been deployed,
it must be replaced with new replace­
ment parts designed and approved espe­
cially for your Audi model version . Re­
placement of complete airbag systems
or airbag components must be per­
formed by qualified workshops only. Make sure that any airbag service action
is entered in your Audi Warranty
& Main­
tenance booklet under
AIRBAG REPLACE­
MENT RECORD .
-For safety reasons in severe accidents,
the alternator and starter are separated
from the vehicle battery with a pyrotech­
nic circuit interrupter.
- Work on the pyrotechnic circuit inter­
rupter must only be performed by a
qualified dealer - risk of an accident!

206 Child Saf ety
- Always install rear-facing child safety
seats on the rear seat.
- If you must install a rearward facing
ch ild safety seat on the front passenger
seat in exceptiona l circumstances and
the
PAS SENGER AIR BA G OFF light does
not come on and stay on, immed iately
install the rear-facing child safety seat in
a rear seating posit ion and have the air­
bag system inspec ted immediately by
yo ur Audi dealer.
_& WARNING
If, in exceptional c ircumstances, you mus t
install a forward -facing child restra int on
the front passenger's seat:
- Always make su re the forward-fac ing
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 man ufacturer's in­
struct ions provided with the child safety
seat or carrier.
- Always move t he passenger seat into its
rearmost position in the seat 's fore and
aft adjustment range, as far away from
the a irbag as poss ible before installing
the ch ild restraint. The backrest must be
adjusted to an upr ight position .
- Always make sure that the
PASSENGER
AIR BAG OFF
light comes on and stays
on all the time whenever the ignition is
switched on.
(D Tips
Always rep lace child rest raints that were
installed in a vehicle during a crash. Dam­
age to a child rest raint that is not visible
could cause i t to fail i n another collisio n
si tua tion.
Advanced front airbag system and
children
Your veh icle is equipped with an "Advanced
A irbag System" in compliance w ith United
States Federal Motor Vehicle Safety Standard (FMVSS) 208 as applicable at the time you
r
vehicle was manufacture d.
T he Adv anced Airbag system in yo ur vehicle
has been certified to mee t the "low-risk" re­
quirements for 3-and 6-year old children on
the passenger side and sma ll adults on the
drive r side. The low r is k dep loyment cr iteria
are intended to red uce the risk of in jury
through interact ion w it h the airbag that can
occur, for example, by being too close to the
steering wheel and instrument panel when
the a irbag inflates . In addition, the syst em
has been ce rtified to comply wit h the "sup­
pression" re quirements o f th e Safety Sta nd­
ard, to t urn off the fron t airbag for infan ts up
to 12 months who are res trained on the front
passenger seat in child restraints that a re list­
ed in the Standard.
E ven though your veh icle is eq uipped wit h an
Advanced Airbag system , a ll children, espe­
cia lly those 12 years and yo unger, should a l­
ways ride in the back seat properly restrained
for their age and size. The airbag on the pas­
senger side makes the front seat a potentially
dangerous place for a ch ild to ride . The front
seat is not the safest p lace for a ch ild in a for­
ward-fac ing ch ild safety seat. It can be a ve ry
dange rous place fo r an infan t or a large r child
i n a rea rward-f acing se at.
Advanced Airbags and the weight­
sensing mat in the front seat
The Advanced A irbag System in your vehicle
detects the presence of an infant or child in a
c h ild restra int on the front passenge r seat us­
i ng the weig ht-sens ing mat in the seat cush ­
ion and the sensor be low th e safe ty belt latch
o n the front passenge r seat that measures t he
tens ion on the s afety be lt.
T he we ight -sensi ng mat measures total
we ight of t he chi ld and the ch ild safety seat
and a c hild b la nk et on the front passenger
seat. The we igh t on the fron t pa sse nger se at
is re late d t o the desig n of the ch ild res trai nt
and its "f ootprint", the s ize and shape o f the
bottom of the chi ld restraint as it sits on the .,..

Intelligent technology Notice about data
recorded by vehicle
control modules
Your vehicle is not equipped with an Event Da­
ta Recorder (EDR), installed by some manu­
facturers for the express purpose of capturing
data for retrieval after an accident or crash
event. EDRs are sometimes called "crash re­
corders".
Some state laws restrict the retr ieval or down­
loading of data stored by EDRs that were in­
stalled 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 electron­
ic control modules for various vehicle systems
such as, for example, engine function, emis­
sion control, as well as for the airbags and
safety belts.
These electronic control modules also record
vehicle-related data during norma l vehicle op­
eration for diagnostic and repair purposes.
The recording capacity of the electronic con­
trol modules is limited to data (no sound is re­
corded) and only a small amount of data is ac­
tually 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 we ll as restraint
system use and performance in the event of a
crash or other condition. Stored data can only be read and downloaded with special equip­
ment.
Intelligent technology 225
Electronic Stabilization
Control (ESC)
General information
The ESC improves the vehicle stability.
. ..---------..
------- -
Fig. 232 Center console with ESC sw itch
ESC is designed to help you maintain vehicle
control in situations where the car approaches
the limits of "grip", especially when accelerat­
ing and cornering. ESC reduces the risk of
skidding and improves stability under all road
condit ions .
The system operates across the entire speed range in combination with the ABS system. If
the Anti-Lock Brake System (ABS) malfunc­
tions, the ESC will also shut down.
How the system works
The Anti-Lock Brake System (ABS), Electronic
Differential Lock (EDL) and the Anti-Slip Regu­
lation System (ASR) are integrated in the Elec­
tronic Stabilization Control. In addition to the
data prov ided by these functions, the ESC con­
trol unit requires additional measurement da­
ta provided by high performance sensors. The
rotational speed of the vehicle about its verti­
cal axis, vehicle acceleration in the fore-and­
aft and lateral directions, the brake pressure and the steering angle are all measured.
T he direction in wh ich the driver wishes to
travel is determined with the aid of the steer­
ing angle and vehicle speed and is continually
compared with the actual behavior of the ve­
hicle. If the two do not match, for example,
when the vehicle starts hydroplaning on a wet
road, ESC will automatically brake the appro-
priate wheel to correct the problem. ..,_
•
•

226 Intellig ent technol ogy
The vehicle is then stabilized by the forces act­
ing on the whee l during braking. If the vehicle
is
oversteering (rear tends to sk id out of the
turn), the brakes are ma inly applied on the
wheel that is on the outside of the curve. In
the case of a vehicle that is
understeering
(tendency to slide out of the curve), the
brakes are applied as needed on the whee l
that is on the ins ide of the curve or addit ional­
l y on the o ther wheels. An acoustic s ignal indi­
cates when ESC b rake app lication cuts in
¢ A .
The system operates across the entire speed
range in combination with the ABS system
¢ page 229. If the Anti-Lock Brake System
(ABS) malfunctions, the ESC wi ll be out of ac­
tion as well .
Activating
When you turn on the engine, ESC w ill auto­
mat ica lly be act ivated and will perform a se lf­
test. As soon as the test is comp leted, the sys­
tem is in normal operating mode.
Offroad mod e
ESC should normally be ope rated in normal
mode because this ensures maximum vehicle
stability. If necessary, you can act ivate the
ESC offroad mode by pressing the but to n
¢ fig . 232 to obtain maximum traction and
braking ability when driving
off paved roads at
l ow speeds. In ESC offroad mode, the indica­
tor light
Ii) ill uminates and the message Sta ­
b ilization control (E S C): Offr oad . Wa rning !
R estric te d stabilit y
appears br iefly in the dis­
p lay .
The ESC offroad mode can be useful in the fo l­
low ing except ional situations when slip or a
h ighly effective differential locking function is
des irable . Examp les:
- when driving with tire chains,
- when driving in deep snow or on loose
ground,
- when driving on uneven surfaces with the
whee ls severe ly unloaded (articulation), and
- when rocking the vehicle loose after it has
become stuck . When the
unusual situation is past, you
sho uld shift back to the norma l ESC operating
mode by pushing the button again . The mes­
sage
S ta b ilizat ion cont rol (ES C): O n then ap­
pears briefly in the display.
H ill desc ent control
The hill descent control is switched on in ESC
offroad mode . When slowly descending steep
gradients on loose ground or when the axles
are articulated, hill descent control provides ass istance by automatically apply ing the
brakes to keep vehicle speed constant. The ve ­
hicle is also rendered easier to steer by selec­
t ive d istr ibut ion of braking force. Hill descent
control intervenes when:
- the acce lerator pedal is not pressed,
- the vehicle is travelling less than 12 mph
(20 km/h),
- a steep gradient is detected,
- wheel behavior indicates loose ground or
conditions with poor adhesion (e .g. also axle
art iculation).
Hill descent contro l operates both d riving for­
ward and in reverse. Active hill descent con­
tro l is deactivated by pressing the accelerator
pedal until the condit ions for activation al­
ready listed are met again .
A WARNING
--
- The Electronic Stabilization Contro l is
neverthe less s ubject to the laws of phys­
ics. It is part icularly important to pay at­
tention to this fact on wet and slippe ry
roads . It i s therefore important that you
always adapt your dr iving to the cond i­
tion of the road and traffic conditions . Do
not a llow the increased safety provided
by the E lectronic Stabilization Contro l
system to lull you into accepting addi­
tional safety risks .
- Please be aware that in ESC offroad
mode, particularly on a smooth and s lip­
pe ry road, the wheels may have an in­
creased tendency to sp in and the vehicle
may b reak away - dange r of skidding!
~