2009 AUDI S8 brake sensor

Driver information display
Yellow symbols
A yellow symbol means WARNING.
Fig. 18 Display: low
fuel level warning
(priority 2)
Yellow symbols indicate a priority 2 malfunction -Warning!
When a y ellow warning symbol appears,
one warn ing ton e sounds.
A driver message appears as well to explain the malfunction in more
detail. The dr iver warning goes out after about
5 s e conds, bu t it can
be brought up again at any time by pressing the [
CHECK I button .
Check the displayed function as soon as possible . If
more than one
priority 2 malfunction is detected, all symbols will appear one after
the other for about
2 seconds .
Yellow symbols mean :
Worn brake pads
Electromechanical
parking brake
=> page 34
=> page 136
Check engine oil level => page 35
=> page 313
Engine oil sensor malfunction => page 35
Low fuel level => page 35
Windshield washer fluid => page 35
level low
Battery voltage
=> page 36
-
II Battery in remote control key => page 48
Convenience key * => page 133
Key not in vehicle
USA models: => page26
Defect ive brake light
Canada models: => page26
Defective brake light
Defective light bulb
=> page26
Engine speed limitation* => page 35
-
IIAdaptive Light* defective => page 36
Dynamic headlight range => page 36
control defective
Defect ive light -/rain sensor
=> page 36
Tire pressure monitoring sys-=> page 43
tern*
Loss of air pressure
-Tire pressure monitoring sys -=> page 46
tern*
ll system not ava ilable
•
Worn brake pads r
Brake pads!

If the warning light illuminates, immediate ly contact your autho ­
ri zed Aud i dealer or qualified workshop to have a ll brake pads
inspected . On USA models the warning light
.1 comes on together
with the warni ng light
BRA KE. Both set s of brake pads on an axle must
a lways be replaced at the same time .
& WARNING
Driving with bad brakes can cau se a colli sion and serious personal
injury.
• If the warning light and the warning light
BRAKE11 with the
mes sage Brake pads ! come s on in the in strument clu ster display ,
immediately conta ct your authorized Audi dealer or qualified
workshop to have all brake pads checked or replaced if nece ssary .•
Checking the engine oil level ~
.... ,. Plea se check oil le vel
When the symbo l illuminates, chec k the eng ine oi l leve l as so on as
possible=>
page 313 . Add oil if necessary=> page 374 . •
Engine oil sensor defective
~ Oil level ! sen sor defective
If the symbo l il luminates, contact your authorized Audi dea ler and
have the oi l sensor inspecte d. Until you have this done, check the o il
level each time you refuel just to be on the safe side=>
page 373. •
11 BRAK E: USA mode ls on ly
Controls and equip ­
ment
Driv er information display
Ap plies to vehic les: wit h eng ine s peed limita tio n
Engine speed limitation
!-1 Engine speed maximum XXXX RPM
The _-symbo l illuminates when there is an engine control malfunc ­
t io n. The indica to r light "in the instrument clus te r also illumi ­
nates . The engine speed is limited to the speed displayed in the
driver info rmation system . Keep in mind that the engine speed wil l
not e xceed the va lue d isplayed in the dr ive r info rm ation system, fo r
examp le when downshifting.
Please go to an au thorized Audi deale r or other qua lif ied workshop
to have the ma lfunction repaired .•
Fuel supply too low l
A Please refuel
When the symb ol i llu minates, this means there are abo ut 2.4
gallons
(9 l itres) of fuel left in the fuel tank . Time to refuel.
=>
page 304 .
If the symbo l lig hts up, eve n w hen there is ample fuel in th e tank,
and the text
Tank system malfunction ! Conta ct workshop appears
i n the d isp lay, t here is a fault in th e sys tem. C ontac t a q ua lified work ­
shop to have the fault rectified .•
' Windshield washer fluid level too low ~
Plea se top up washe r fluid
If t he symbo l illum inates, add windshie ld washe r fluid to the washe r
system and a lso to the headlight washer system=>
page 325. •
I • •

__________________________________________ ...;A~d~a~p~t~iv~e~C~ru~is~e~C:_:o~n~t!..ro~I _J __
Adaptive Cruise Control
Speed and distance control system
Applies to vehic les : with Adaptive C ruise Cont rol
Description
The Adaptive Cruise Control driver assistance program is
a combined speed and distance control system.
Fig. 151 Front
bumper: Position of
radar sensor
Adaptive Cruise Control can help make driving more relaxed and
less tiring, particularly during long trips on interstates or other
highways that are generally straight .
Set ACC to maintain a constant, legal travel speed between 20 and
95 mph (30 -150 km/h) that is appropriate for prevailing traffic
conditions. Select a following distance to the vehicle ahead and ACC
will adjust your speed to maintain that distance .
Adaptive Cruise Contro l has technical limitations that you must
know, so please read this section carefully, understand how the
system works and use it proper ly at all times .
How does it work?
You can operate the Adaptive Cruise Control using the lever on the
steering wheel column =>
page 142, "How is the speed stored?" and
=>
page 144, "How is the distance set?" .
Contro ls and eq uip­
ment
Driver information
Important information is brought up in the speedometer and in the
instrument cluster display as the vehicle is being driven
=> page 146, "Driver information" .
What is important for you to know
There are limits to what Adaptive Cruise Control can do as the
vehicle is being driven =>
page 150, "System limitations" .
& WARNING
Improper use of the Adaptive Cruise Control can cause collisions,
other accidents and serious personal injury.
• Always remember that the Adaptive Cruise Control has limits -
it will not slow the vehicle down or maintain the set distance
when you drive towards an obstacle or something on or near the
road that is not moving, such as vehicles stopped in a traffic jam,
a stalled or disabled vehicle.
• Always remember that the Adaptive Cruise Control cannot
detect a vehicle that is driving towards you in your traffic lane and
that it cannot detect narrow vehicles such as motorcycles and
bicycles .
• Never drive at speeds that are too fast for traffic, road and
weather conditions .
• The Adaptive Cruise Control cannot slow or brake the vehicle
safely when you follow another vehicle too closely. Always
remember that the Adaptive Cruise Control has a braking power
that is only about 30% of the vehicle 's maximum braking ability.
Always be prepared to brake and take evasive action to avoid colli­
sions and other accident situations.
• Never allow the closing speed between you and other vehicles
to be so high that the Adaptive Cruise Control may not be able to _,,,
Vehicle care I I irechnical data

• .___A_ d_a_ p:- t_iv _ e_ C_ r_u _is _ e_C_ o_ n_ t_ r_ o_ l --------------------------------------------
& W ARN ING (continued )
slow your veh icle safel y. If closing speed is too h igh , you must
apply the brake s your self to reduce the risk of a rear -end cra sh.
• Never rest your foot on the accelerator pedal , especi ally when
the Adapt ive Crui se Control is being u sed . Pressure on the acceler ­
ator will override the ACC brak ing function and prevent the brakes
from being applied when ACC detect s a situation when the brake s
must be applied .
• Never use Ad aptive Cruise Control when you cannot drive
safely at a steady speed , including on city streets , on winding
roads or when road condition s are poor (for example, on i ce ,
gravel , in fog , heavy rain or on wet roads that in crease the risk of
hydroplaning).
• The radar sensor's
vision can be redu ced by rain , snow and
heavy road spray . These and similar conditions can prevent vehi ­
cles up ahe ad from being a ccurately detected and in some cases
they may not be detected at all . Do not use ACC when the radar
sensors cannot ac curately detect vehi cles moving ahead of you in
traffic.
• Always turn off Adaptive Cruise Control when entering turn
lanes, exit lanes and construction zones or in similar situations
be cause the vehicle will automati cally ac celerate to the stored
speed when the road ahead is clear.
• To p revent unintended operation , always switch ACC off when
it is not being used.
[ i ] Tips
• For safety r eas ons, the store d spe ed is d elet ed whe n th e ig nition
is turned off .
• When Ada ptive Cru ise Contr ol is swi tch ed o n, the Electr onic
Stabilization Program (ES P) is also automatically activated .
• Damage caused by accidents an d so me min or collis ions ca n
affect the radar sensor settings and cause the system to malfunc ­
t ion o r sw itch o ff co mplet ely . • I
n winter conditions, you should check the radar sensor cover
b ef or e driving to make s ure it is free of ice and snow . If n ecessary,
clean the area near the radar sensor carefully=:>
page 139, fig. 151 .
• To ensu re tha t the rada r se nsor is not bl ocked, fo reign objec ts
(e .g. stickers, larger license p late mounts, add -on parts) must not
cover the area near the rada r sens or=:>
pag e 139, fig. 151. The area
near the radar sensor must not be painted, either.
• For Dec laration of C ompliance to U nited S ta te s FCC an d Ind ustry
Canada regulations=>
page 385. •
Appl ies to vehic les: w ith Ada ptive Cru ise Contro l
How does Adaptive Cruise Control work?
Vehicles tr aveling ahead are detected with t he aid of the
ra da r se nsor.
Fig . 152 R adar sen sor
mea suremen t range
Adaptive Cr uise C ontr ol us es a radar senso r in the fron t of th e
vehic le=:> fig. 152 . The system has limitations=:>
page 150. Things
th at are n ot moving in yo ur l ane and i n you r direc tio n of travel wi ll
n ot be detected. The sensor measures the distance to reflective
surfaces that must have a certain size. The system responds only
after t he distance measurement has been made. If a measurement
is not possible, the system cannot respond and wi ll not react to a
v e hic le or so met hing else up ahe ad .
~

_____________________________________________ A_ d_a ...: pc.. t _i_ v _e_ C_ ru_ is_ e_ C_ o_n_ t_ r_ o _ l __ fflJI
A CC no t avai la bl e
The text message ACC n ot av aila bl e appears, for examp le, if the
temperature of the brakes is excessive. Adaptive Cruise Contro l is
temporari ly not available . A warning tone sounds as a reminder.
A CC no t avai lable!
The text message ACC not avai la ble! appears in the event of a
malfunction. Adaptive Cruise Control is turned off. A warning tone
sounds as a rem inder. Have the system inspected by a qua lified
dea lership.
A CC sen sor bloc ked
The text message AC C se nsor b lo cked appears when the ACC
System does not detect any objects over an extended time period .
For the time being, the distance to vehicles up ahead is not being
controlled. The ACC system is not switched off, so increased a lert­
ness is required. The following may be reasons for the text message
ACC sensor blocked:
• The ACC sensor is d irty. The ACC system is not reacting, or is not
reacting correctly, to vehicles trave ling ahead .
• It is possible that you are dr iving on a road with very light traffic
without anything at the side of the road (e.g. guard rai ls, traffic
s igns, trees) . As soon as a vehicle is detected by the system aga in,
it returns to its control range and the text message disappears .
The ACC sensor is located in the area under the front license plate .
If there is a loss of operation due to heavy contamination, this area
should cleaned to restore proper operation.
A CC se nso r blo cked !
The text message ACC sen sor blocked! appears when the ACC
System can no longer accurately detect vehic les moving up ahead
in your lane of travel. Adapt ive Cruise Cont rol is tu rned off . A
warning tone a lso sounds as a reminder.
T o decide whether it is necessary to switch off the ACC (ACC sensor
b locked!) o r if it is on ly a temporary condition (ACC sensor blocked),
Controls and equip ­
ment
the system will also takes into consideration the outside tempera ­
t ure and/or the windshield wiper operation.
The ACC sensor is dirty or blocked (e.g. leaves, snow).
The ACC sensor is located in the area under the front license plate .
I f the ACC sensor is d irty or blocked, clean the area to restore system
operation .
EPB acti vation
The text message EPB a cti vation appears if emergency braking was
initiated with the Electromechan ical Parking Brake (EPB) . Adaptive
Cruise Control is turned off. A gong sounds as a reminder.
ESP activ at ion
The text message E S P activ ation appears if the Electronic Stabiliza ­
tion Program (ESP) has intervened to take control in a critica l driving
situation. In this case Adaptive Cruise Control is automatically
turned o ff. A gong sounds as a reminder .
Speed r ange
The text message Sp eed r ange appea rs if the current speed is too
low
to set or to hold the requested speed.
When se tting a desired speed, it must be a t leas t 20 m ph (30 km/h).
At speeds below 17 mph (25 km/h), the cruise control is turned off.
Shift le ver po sition!
The text message Shift lever po sition! appears when the shift se lect
leve r is m oved to position
N. In this position, Adaptive Cruise
Control is not avai lable .•
I • •

Adaptive Crui se Control -
---------------=-------'
Applies to vehicles: with Adaptive Cru ise Co nt rol
When driving around curves
k;;;:;::;;;;~==========; ~
o5
J
Entering a curve
Fig . 1 63 V eh ic le
enterin g a c urve
F ig . 164 Vehicle
l ea ving a curv e
When entering a curve, the Adaptive cruise control may react to a
vehicle in the next lane and apply the brakes in your vehicle
=> fig . 163 . The braking action can be overridden by depressing the
accelerator pedal.
L e avi ng a cu rve
At the end of very long curves, ACC 's predictive lane reading can
cause ACC to react to a nother vehicle in the next lane and app ly the
brakes on your vehicle=> fig. 164 . T he braking action can be over ­
ridden by depressing the accelera tor pedal. •
Contro ls and eq uip­
ment
Ap plies to veh icles: with Adapt ive Crui se Contro l
Vehicles offset to one side
Fig . 165 V ehi cle tra v­
e ling ahe ad outsid e th e
d etec tion r ange of the
ra dar se nsor
Vehic les moving up ahead but offset in the lane cannot be detected
by ACC until they are in sensor range. •
Applies to veh ic les: with Adaptive Cruise Co nt ro l
Lane changes by other vehicles
Fig . 166 A veh ic le
c han ges la ne s
Vehicles that cut into your lane a short distance in front of you
cannot be detected by ACC until they are in sensor range. •
Vehicle care I I irechnical data

___ ln_ t _e_ ll-'"ig ...,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
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.
I~
"' " "'
- -
( ra I 5£ IA I -3, )
Fi g. 256 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, the lateral acce leration
acting on the vehicle, the brake pressure and the steering angle are
a ll 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 at the
rear wheel that is on the inside of the curve . An acoustic signal indi­
cates when ESP brake application cuts in
~ & .
The system operates across the entire speed range in combination
with the ABS system
~ page 274 . If the Anti -Lock Brake System
(ABS) malfunctions, the ESP wi ll be out of action as well.
Ac tivat ion
When you turn on the eng ine, ESP will automatically be activated
and will perform a self -test.
The system can be activated or deactiva ted by pressing the button
~ page 270, fig. 256. The warning light comes on when the system
is switched off
~ page 18.
Normally , the ESP should always be on, however, it may be advanta­
geous to turn off the system in certain special cases when some
degree of wheel spin is desired such as :
• when driving with snow chains
• when driving in deep snow or on a loose surface (to allow the
wheels to dig in to reach firm ground)
• when trying to "rock" the vehicle free when it has beco me stuck.
T he system should be reactivated once you are no longer in such
situations .
Both the ABS and EDS systems are still functioning even if the ESP
is switched off .
Controls and equip­
ment Safety first Vehicle operation
In
te llig ent tec hn olo gy
& WARNING
The Ele ctron ic St abiliz ation Progr am i s ne ve rt h el ess s ubject to the
laws of ph ysics. It i s particularl y important t o pay attention t o th is
f ac t on wet an d slipp ery road s. It i s th ere fore important that you
alway s adapt your driving to the condition of the road and traffic
c onditio ns. Do n ot allow the in crease d sa fety p ro vi ded by t he El ec­
tronic Stabiliz ation Program sy stem to lu ll you into a ccepting
a dditional safety ri sk s.
c
Electronic differential lock (EDL)
The electronic differential lock monitors the rotation al
s p eed of the drive wheels.
G en era l not es
The elect ronic differential lock (EDU helps the car to start moving,
accelerate and c limb a gradient on surfaces providing poor or
a lmost no grip . Without EDL , this would be difficult, if not impos ­
s ib le.
How the system works
The EDL operates automatical ly. It monitors the rotational speed of
the drive wheels on an axle with the he lp of the ABS sensors
~ page 274. If a noticeable difference in rotational speed between
the drive wheels on one axle is detected (e.g. on slippery ground on
one side), the spinning w heel is braked, thereby transferring power
to the other drive wheel or wheels (all -whee l 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 .
Dri ving off
When driving off, always be sur e to ke ep road conditions in mind as
you accelerate. I f one drive wheel spins because it is on a surface
with less grip, gradual ly increase the pressure on the accelera tor
pedal unt il the car star ts to
move . The whee l less able to t ra nsfer
power spins. _.,
Vehicle care Do-it-yourself service Technical data