sensor AUDI A4 AVANT 2008 Owner's Manual

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• 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
the weight -sensing mat to measure more weight than is actually on
the seat.
If the PASSENGER AIR BAG OFF light still does not come on and does
not stay on continuously (when the ignition is switched on),
• take the child restraint off the front passenger seat and install it
properly at one of the rear seat positions. Have the airbag system
inspec ted by your Audi dealer immediately .
• move the child to a rear seat position and make sure that the
child is properly restrained in a child restraint that is appropriate for
its size and age.
The
PASSENGER AIR BAG OFF light should NOT come on when the
ignition is on and an adult is sitting in a proper seating position on
the front passenger seat. If the
PASSENGER AIR BAG OFF light
comes on and stays on or flashes for about 5 seconds while driving,
under these circumstances, make sure that:
• the adult on the front passenger seat is properly seated on the
center of the seat cushion with his or her back up against the back ­
rest and the backrest is not
reclined~ page 168, "Proper occupant
seating positions",
• the adult is not taking weight off the seat by holding on to the
passenger assist handle above the front passenger door or
supporting their weight on the armrest,
• the safety belt is being properly worn and that there is not a lot
of slack in the safety belt webbing,
• accessory seat covers or cushions or other things that may cause
an incorrect reading or impression on the weight-sensing mat
under the upholstery of the seat have been removed from the front
passenger seat, •
a safety belt extender has not been left in the safety belt latch for
the front passenger seat.
In addition to the
PASSENGER AIR BAG OFF light in the center of the
instrument panel, the message
PASSENGER AIR BAG OFF or
PASSENGER AIR BAG ON will briefly appear in the instrument cluster
display. This is to inform the driver of the current front passenger
airbag status. •
Important safety instructions on monitoring
the Advanced Airbag System
& WARNING
An airbag system that is not functioning properly cannot provide
supplemental protection in a frontal crash.
• If the airbag indicator light comes on, it means that there may
be something wrong with the Advanced Airbag System. It is
possible that the airbag will inflate when it is not supposed to, or
will not inflate when it should.
• Have the airbag system inspected immediately by your Audi
dealer.
& WARNING
If the front airbag inflates, a child without a child restraint, in a
rearward-facing child safety seat or
in a forward-facing child
restraint that has not been properly installed will be seriously
injured and can be killed .
• Even though your vehicle is equipped with an Advanced Airbag
System, make certain that all children, especially 12 years and
younger, always ride on the back seat properly restrained for their age and size .
• Always install forward or rear-facing child safety seats on the
rear seat -even with an Advanced Airbag System.
.,_

-Airbag system ---=--.:..,.._ _________________________________ _
&, WARNING (continued )
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 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 specifically approved by
Audi.
- Never use additional seat cushions that cover the areas
where the side airbags inflate.
- Damage to the original seat covers or to the seam in the area
of the side airbag module must always be repaired immedi­
ately by an authorized Audi dealer .
• The airbag 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 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 a irbag service action is entered in your Audi
Maintenance
& Warranty booklet under AIRBAG REPLACEMENT
RECORD .
• In accidents when an airbag is deployed, the vehicle battery
separates the alternator and the starter from the vehi cle electrical
system for safety reasons with a pyrotechnic circuit interrupter.
-Work on the pyrotechni c circuit interrupter must only be
performed by a qualified dealer -risk of an accident !
&, WARNING (continued )
-If the vehicle or the circuit interrupter is scrapped, all appli­
cable safety precautions must be followed.
•
Other things that can affect Advanced Airbag performance
Changing the vehic le 's suspension system can change the way that
t he A dvance d Ai rbag S ystem p erf o rm s in a c rash. F or example,
using tire -rim combinations not approved by Audi, lowerin g the
ve hicle , ch ang ing the stiff ness of the suspe nsion, includ ing the
springs, suspension struts, shock absorbers etc. can chang e the
fo rces that a re measured by the airbag senso rs and se nt to the elec­
tronic control u nit. Some suspension chan ges can, for exampl e,
i n crease the fo rce level s measured by the sen so rs and ma ke the
a irbag s yste m de plo y in cras he s in w hi ch it wou ld not de ploy if th e
changes had not been made. Other kinds of changes may reduce
t h e fo rce lev els measu red by the senso rs a nd p reven t the airb ag
from dep loying when it should.
T he sens ors i n the safe ty belt buckle f or the dri ve r and front
passeng er seat tell t he electronic contro l modu le if the safety belt is
la tched o r not. If t he sa fe ty bel t i s being used, the fro nt ai rbag wi ll
deploy at a s ligh tly high er rate o f veh icle dece lerat io n th an if th e
safety be lt is not being u sed . Th erefo re , in a particula r co llision, it is
poss ib le th at a n airbag will not deplo y at a seat ing po sit io n wh ere
the safety be lt is being used but wi ll inflate at the pos ition where the
safety be lt is not bei ng used . It is im po rta nt tha t noth ing i nte rfere
with the safety belt buc kles so that the sensors can send the correct
i nf orm atio n abou t s afe ty belt use to th e electr onic co ntrol uni t.
~

& WARNING
Changing the vehicle's suspension including use of unapproved
tire-rim combinations can change Advanced Airbag performance and increase the risk of serious personal injury in a crash.
• Never install suspension components that do not have the
same performance characteristics as the components originally
installed on your vehicle.
• Never use tire-rim combinations that have not been approved
by Audi.
& WARNING
Items stored between the safety belt buckle and the center
console can cause the sensors in the buckle to send the wrong
information to the electronic control module and prevent the
Advanced Airbag System from working properly .
• Always make sure that nothing can interfere with the safety
belt buckles and that they are not obstructed . •
Safety first
Airbag system
Side airbags
Description of side airbags
The airbag system can provide supplemental protection
to properly restrained occupants.
Fig. 181 Side airbag
location in the driver's
seat
The side airbags are located in the sides of the front seat backrests
=> fig. 181 and the rear backrest* facing the doors. They are identi­
fied by the word "AIRBAG".
The side airbag system basically consists of: • the electronic control module and external side impact sensors
• the two side airbags located in the sides of the front backrests
• two rear side airbags (as an ordered
option)
• the airbag warning light in the instrument cluster .
Th e airbag system is monitored electronically to make certain that
it is functioning properly at all times. Each time you turn on the igni­
tion, the airbag system indicator light will come on for a few
seconds (self diagnostics).
The side airbag system supplements the safety belts and can help
to reduce the risk of injury to the driver's, front and rear*
.,_
irechnical data

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passenger's upper torso on the side of the vehicle that is struck in a
side co llis ion. The airbag dep loys on ly in side impacts and only
when the vehic le acce leration registered by the control unit is high
enoug h. If this rate is below the reference va lue programmed into
the control unit, the side airbags will not be triggered, even though
the car may be badly damaged as a resu lt of the collision . It is not
possible to define an airbag trigger ing range that wi ll cover every
possible angle of impact, since the circumstances will vary consid ­
erab ly between one coll ision and another. I mportant factors
inc lude, for example, the nature (hard or soft) of the impacting
object, the angle o f impact, vehicle speed,
etc .=> page 205, "I m por ­
tant safety instructions on the side airbag system".
Aside from their normal safety funct ion, safety be lts work to help
keep the driver or front passenger in posit ion in the event of a side
collision so t hat the side airbags can provide protection.
The airbag system is
not a substitute for your safety belt. Rather, it
is part of the overa ll occupant restraint system in your vehicle .
A lways re m ember that t he side airbag system can on ly he lp to
protect you if you are wearing your safety be lt and wearing it prop ­
e rly. This is a nother reason why yo u should a lways wear you r safety
belts, not just because the law requires you to do
so=> page 176,
"General notes".
It is important to re m em ber that while the supp lemental side airbag
system is designed to reduce the like lihood of serious injuries, other
injuries, for example, swel ling, bru is ing, and minor abrasions can
a lso be associated with deployed side airbags. Remember too, side
a irbags wil l deploy o nly once and on ly in certain kinds of accidents
- your safety belts are a lways there to offer protection.
Vehicle damage, repair costs or even the lack of vehic le damage are
not necessari ly an indication of over-sensitive or failed airbag acti ­
vation. In some collisions, both front and side airbags may inflate.
Reme mber too, that a irbags w ill dep loy on ly once and on ly in
certain kinds of col lisions -your safety belts are always there to
offer pro tec tion in those acc ide nts in whic h airbags are not
supposed to deploy or when they have already deployed. T
he s ide a irbag sys te m will not d eplo y:
• whe n the ign ition is turned off
• in side collisions when the acce leration measured by the sensor
is t oo low
• in front-end co llisions
• in rear-end co llisions
• in ro llovers .
I n some types of accidents the front airbags, side curta in airbags
and side airbags may be triggered together.
& WARNING
• Safety belt s and the airbag sy stem will only prov ide protection
when occupant s are in the proper se ating posit ion
=> page 2 05 .
• If the airbag indic ator light come s on when the vehicle i s being
u sed , ha ve the sy stem inspe cted immed iat ely by y our authorized
Audi d ealer . The airbag may not work properly when the vehicle
a cc eler ation in a side colli sion is high enough to acti vate the
airba g.•

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&, WARNING (continued )
-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 in crease the risk of
injury in an accident by interfering with the way the airbag unfolds
or by being pu shed into you as the airbag inflates .
- Never place or attach accessories or other objects (such as
cup holders , telephone brackets , or even large , bulky objects)
on the doors , over or near the area marked
"AIRBAG" on the
seat backrests .
- Such objects and accessories can become dangerous projec ­
tiles and cause injury when the supplemental side airbag
deploys.
- Never carry any objects or pets in the deployment space
between them and the airbags or allow children or other
passengers to travel in this position .
• 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 per sonal injury in an accident.
• Alway s prevent the side airbags from being damaged by heavy
objects knocking against or hitting the sides of the seatba cks .
• 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 author ized Audi dealer.
• If children are seated improperly , their risk of injury increases
in the case of an
accident => page 210, "Child Safety".
&, WARNING (continued )
• 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
c losed.
- 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 .
•

Side curtain airbags (SIDEGUARD™)
Description of SIDEGUARD™ airbags
The SIDEGUARD™ airbag system can provide supple­
mental protection to properly restrained occupants.
F ig . 18 3 S IDEGUARD ™
sys tem , driver's s id e:
s id e cu rtain air b a g
l oca tio n
The side curtain airbags are located on both sides of the interior
above the front and rear side
windows => fig. 183 . They are identi ­
fied by the word "AIRBAG" on the windshield frame and the center
roof pillar.
The side curtain airbag system supplements the safety belts and can help to reduce the risk of injury for occupants' heads and upper
torso on the s ide of the vehicle that is struck in a side collision . The
side curtain airbag inflates only in side impacts and only when the
vehicle accele ra tion reg istered by the contro l unit is high enough. If
this rate is below the reference va lue programmed into the contro l
unit, the side airbags w ill not be triggered, even though the car may
be badly damaged as a result of the co llision . It is not possible to
define an airbag triggering range that will cover every possible
angle of impact, since the circumstances will vary considerably
between one collision and ano the r. Important factors include, for
example, the nature (hard or soft) of the impacting object, the angle
Safety first
Airb ag syst em
of impact, vehicle speed, etc .=> page 208, "How side curtain airbags
work".
Aside from their norma l safety function, safety belts work to help
keep the driver or front passenger in position in the event of a colli ­
s ion 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 restrain t system in your veh icle.
Always remember that the airbag system can only he lp to protect
you if you are wear ing your safety belt and wear ing 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 176, "General
notes".
It is important to remember that while the side curtain airbag
system is designed to help reduce the likelihood of serious injuries,
other injuries, for examp le, swelling, bruising, and minor abrasions
can a lso be associa ted with these a irbags . Remembe r too, these
airbags will deploy only once and on ly in certain kinds of accidents
- your safety belts are always there to offer protection .
The side curta in air b ag system b asi cally consists of :
• The elec tronic co ntrol mod ule and external side 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 electronica lly to make certain it is
f u n ction ing properly at all times. Each time you turn on the ignition,
the airbag system indicator light wi ll come on for a few seconds
(se lf diagnostics).
The s ide curt ain ai rbag is not acti vated :
• if the ignition is turned off,
• in side collisions when the acceleration measured by the sensor
is too low,
• in front -end collisions,
• in rear -end collisions,
.,
irechnical data

& WARNING (conti nued )
• Alw ays install r ear-facing child saf ety s eats on the r ear seat.
• If you mu st in sta ll a re arwa rd f acing child safe ty s eat on the
front pas senger seat in exc eptional cir cum stances and the
PASSENGER AIR BAG OFF light doe s not come on and stay on,
immediat ely install th e rear-fa cing child safety s eat in a rear
s e ating po sit ion and h ave the airb ag sys tem in spe cted immedi ­
a tel y by y our Audi dealer .
& WARNING
If, in exceptional circum stance s, you must in stall a forward -fac ing
c hild re st ra int on the fr ont p assenge r's s eat:
• Alway s make sure the forward -facing seat ha s been de signed
and cert ified by it s m anuf acturer for u se on a front se at with a
pa ssenger front and side airbag .
• Always follow the m anufacturer's instruct ions provided w ith
the child safet y seat or c arrier.
• Alway s m ov e th e passeng er sea t into it s re arm ost p osit ion in
the seat' s fore and aft adju stment range , as far away from the
a irb ag as possible before installin g the ch ild r estr aint . The b ack­
rest must be adjusted to an upright po sition.
• Alway s ma ke sure th at the PASSENGER AIR BAG OFF light
come s on and stay s on all the time wheneve r the ignition i s
s wit ched on . •
Advanced front airbag system and children
Your vehicle is equipped with a dual -stage front "Advanced Airbag
System" in comp liance with United States Federal Motor Vehicle
Safety Standard ( FMVSS) 208 as applicab le at the time your vehic le
was manufactured .
Controls and equip­
ment Safety first Vehicle operation
Chi
ld Sa fe ty
The Advanced Airbag system in your vehic le has been certified to
meet the " low -risk" require ments for 3 and 6 yea r- old c hild ren on
the passenger side and small adu lts on the driver side . The low risk
deployment c rite ria are intended to reduce the risk of inju ry th rough
interaction with the airbag that can occur, for example, by being too
close to the steering whee l and instrument panel when the airbag
in flates . In add it ion, the system has been cert ified to comply with
the "suppression" requirements of the Safety Standard, to turn off
the front airbag for in fants up to 12 months who are restrained on
the front passeng er seat in child restraints that are listed in the
Standard.
Even though your vehic le is equipped with an Advanced Airbag
system, all ch ildren, especially those 12 years and younger, sho uld
a lways ride in the back seat proper ly restra ined for the ir age and
size . The airbag on the passenger side makes the front seat a poten ­
tially dangerous p lace for a chi ld to r ide. The front seat is not the
safest p lace for a chi ld in a forward -facing child safety seat. It can be
a very dangerous place for an infant or a larger chi ld in a rearward ­
facing seat. •
Advanced Airbags and the weight-sensing
mat in the front seat
The Advanced A irbag System in your ve hicle detects the p resence
of an infant or chi ld in a child 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 meas ures total we ig ht of the ch ild and the
child safety seat and a chi ld blanket on the front passenger seat. The
weight o n the fr ont passenge r seat is related to the desig n 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 chi ld
_..
Vehicle care Do-it-yourself service Technical data

___ C_ h_il _
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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 typical infants and typical 1 year­
old child have been stored in the control unit of the Advanced
Airbag System. When a child restraint is being used on the front passenger seat with a typical 1 year-old 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 child restraint is properly
installed at one of the rear seating positions. If in exceptional
circumstances you must use it on the front passenger seat, carefully read all of the information on child safety and Advanced Airbags
and heed all of the applicable WARNINGS. Make certain that the
child restraint is correctly recognized by the weight -sensing mat
inside the front passenger seat, that the front passenger airbag is
turned off and that the airbag status is always correctly signaled by
the
PASSENGER AIR BAG OFF light. Many types and models of child restraints have been available over
the years, new models are introduced regularly incorporating new
and improved designs and older models 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 child restraint
that sits on the seat, when they are installed on a vehicle seat. These
differences make it virtually impossible to certify compliance with
the requirements for advanced airbags with each and every child restraint that has ever been sold in the past or will be sold over the
course of the useful life of your vehicle.
For this reason, the United States National Highway Traffic Safety
Administration has published 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. Rear facing child restraint systems, manufactured
on or after September 1, 2004:
(When the restraint system comes equipped with a removable base,
compliance has to be 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 Infant 8457

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Intelligent technology
Notice about data recorded by
vehicle control modules
Your vehicle is not equipped with an Event Data Recorder (EDR),
installed by some manufacturers for the express purpose of
capturing data for retrieval after an accident or crash event . EDR's
are sometimes called "crash recorders" .
Some state laws restrict the retrieval 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
we ll
as for the airbags and safety belts.
These electronic control modules also record vehicle-related data
during normal vehicle operation for diagnostic 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 vehic le speed, d irection,
braking as well as restraint system use and performance in the
event of a crash or other condition . Stored data can only be read and
down loaded with special equipment. •
Electronic Stabilization Program (ESP)
General information
The ESP improves the vehicle stability.
(X) CD
Fig. 199 Center
console with ESP
sw itch
ESP is designed to he lp you maintain vehic le control in situations
where the car approaches the limits of "grip", especial ly when
acce lerating and cornering. ESP reduces the risk of skidding and
improves stability under al l road conditions.
The system operates across the entire speed range in combination
with the ABS system . If the Anti-Lock Brake System (ABS) malfunc ­
t ions, the ESP will a lso shu t down.
How the system works
The Anti-Lock Brake System (ABS), Electronic Differential Lock (EDU
and the Anti -Slip Regu lation System (ASR) are integrated in the e lec ­
tronic stabilization program . In addition to the data provided by
these functions, the ESP control unit requires additional measure ­
ment data provided by high performance sensors. The rotational
.,,.

-Intelligent technology
------~----- ~~--------------------------------------
one side), the spinning wheel is braked, thereby transferring power
to the other drive wheel or wheels (all- wheel drivel. 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 control led.
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, gradual ly increase the pressure on the accelerator
pedal until the car starts to move. The wheel less able to transfer
power spins.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads, the EDL cuts out temporarily. The
veh ic le remains operational and behaves in the same way as a
vehic le 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
ca n 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 21. •
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 sp inning by adjus tin g the
engine power to match the amount of grip availab le from the road
surface.
How the system works
ASR performs automatical ly, i.e . w ithout the driver's intervention.
With the aid of the ABS
sensors=> page 240, ASR monitors the
speed of the driven wheels. If the wheels start to spin, the engine
power 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 shou ld
occur in the ABS, the ASR will also be out of act ion.
Activation
The ESP is automatica lly activated when the eng ine is started, and
it performs a self-test. You can activate a deactivated ASR, if
requ ired, by pressing
t h e=> page 236, fig . 199 button .
Deactivation
You can deactivate the ASR, if required, by pressing the button (for
less than 3
seconds) => page 236, fig. 199. With the ASR deactivated,
the ESP check light flashes,
see=> page 22.
Normally, the ESP shou ld always be on, however, it may be advanta­
geous to turn off the system in certai n special cases when some
degree of wheel spin is desired such as :
• when driving with snow chains