AUDI S8 2009 Owners Manual

__________________________________________ ...;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

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& 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 .
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Vehicles moving in you r direction can be detected up to a dis tance
of about 140 yards (130 meters) bu t the Adaptive Cruise Control
cannot detect vehicles that are stopped or sta lled, obs tacles that do
not move or narrow vehic les like motorcyc les and bicycles .
Open road
When the road is c lear, Adap tive Cruise Con trol works like cruise
control. It maintains a constant target speed specified by the driver .
Driving in traffic
If a slow er vehicle driving ahead is detected, the Adaptive Cruis e
Contr ol dece lerates (within the limits of the system) ::::,
page 150 to
its spe ed and after adjusting, tries to maintain the set distance from
t he veh ic le ahead. The vehicle may temporar ily d rive slower tha n
the set speed while adjusting ::::,
& in "Description" on page 139.
If the vehicle in front accele rates, Adaptive Cruise Control also accel ­
erates up to the speed that you have set.
Situations requiring driver intervention
I n some situations you w ill have to use the foot brake and slow the
veh icle down in order to keep a sa fe distance from vehicle in front
of you or to avoid a rear -end collision. In this situation, a symbol
appears and a warning tone sounds::::,
page 146.
Passing another vehicle
If you move int o the pa ssing lane and no vehicle is detecte d ahead,
Adaptive Cruise Contro l accelerates to the speed you have set and
maintains it .
Overriding ACC
You can increase your speed a t any time by stepping on the acceler ­
ator pedal. After you re lease the accelerator pedal, the system
adjusts back down to the speed you previously set .
Contro ls and eq uip­
ment
& WARNING
• Never rely on the distan ce control feature of ACC alone to
prevent rear -end collisions. Always be prepared to brake and take
evasive action to avoid colli sio ns and other accident situation s.
• Never allow the closing speed between you and other vehicle s
to be so high that the Adaptive Cruise Control may not be able to
slow your vehicle safely . If clo sing speed i s too high , you must
apply the brakes yourself to reduce the risk of a rear -end cra sh .
[ i ] Tips
Please note that the amount of acceleration the Adaptive Cruise
C o ntro l use s depends on the Distance setting selected . DISTA NCE 1
gives you acceleratio n that is dynamic a nd sporty. D IS TA NCE 4, on
the other hand, gives more moderate acceleration . For more infor ­
mation about the ti me inte rvals ::::,
page 144, "How is the distance
set?". •
Applies to veh ic les : wi th Ad aptive Cr uise Co ntro l
Switching the system on and off
Switching the system on
- Pull the le ver t o positi on G) .
Vehicle care I I
Fig . 15 3 Contr ol le ver:
Sw itch ing on an d off
irechnical data

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Switching the system off
-Press the lever to position @(latched). •
Applies to veh icles: with Adapt ive Cruise Cont rol
Hovv is the speed stored ?
'° "' M
Fig. 154 Control lever:
Storing speed
With the system switched on the speed is stored as follows:
- Drive at the speed you want. The speed must be between 20 and 95 mph (30 and 150 km/h).
- Press the SET button to store the desired speed.
After the (SETI button is released, the current speed is stored and
maintained.
The instrument cluster display shows the stored speed with a red
indicator light~
page 146.
[ i ] Tips
For safety reasons, the stored speed is erased when the ignition or
the ACC is turned off.•
App lies to vehic les: w it h Adapt ive Cruise Contro l
Changing stored speed
Speed can be changed without touching the accelerator
or brake pedal.
Increasing speed
....
"' M ~ w .,
"'
Fig . 155 Control lever:
Changing speed
- Press the lever briefly upwards Q. USA models: Speed
increases by about 2.5 mph. Canada models: speed will
increase by one mark on the speedometer scale.
- Press the lever upwards
Q and hold it. As long as you
hold the lever up, the light diode display in the speedom­
eter LED display moves forward and the speed is
increased.
Reducing speed
- Press the lever briefly downwards Q. Speed decreases
by 2.5 mph. Canada models: speed will decrease by one
mark on the speedometer scale.
- Press the lever downwards
O and hold it. As long as you
hold the lever down, the light diode display in the speed ­
ometer LED display moves backward and the speed is reduced. ._

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After releasing the control switch, the system regulates the speed to
the value just set.
& WARNING
Improper use of the Adaptive Cruise Control features and inatten­
tion can lead to an accident causing serious personal injury.
• It is dangerous to use the "RESUME" feature when the previ­
ously set speed is too high for existing road, traffic or weather
conditions.
• Always read and heed the information and WARNINGS =>
& in
"Description" on
page 139.
[ i] Tips
You can increase your speed at any time by stepping on the acceler­
ator pedal. After you release the accelerator pedal, the system auto ­
matically adjusts back down to the speed you previously set . A new
desired speed can be stored at any time by pressing the [SET)
button =>
page 142, fig. 154. •
Contro ls and eq uip­
ment
A pp lies to veh icles: w it h A dapt ive Crui se Contro l
Turning Adaptive Cruise Control off
temporarily
In some situations it makes sense to turn Adaptive Cruise
Control off temporarily.
Turning control off temporarily
Step on the brake pedal or
Fig. 156 Control lever:
Turning Adaptive
Cruise Control off
temporarily
Press the control lever in the direct ion of the arrow 0
(not latched) => fig. 156.
Reactivating control
To resume the stored speed, release the brake pedal and
press the control lever in the direction of the arrow
G) .
& WARNING
Improper use of the Adaptive Cruise Control can cause collisions,
other accidents and serious personal injuries.
• Never resume the stored speed if the speed is too high for
prevailing road, traffic or weather conditions. ..
Vehicle care I I irechnical data

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[ i J Tips
When the system is turned off temporarily, the speed set at that
time is stored .•
Ap plies to ve hic les: wit h Ad aptive Cruise Contro l
Hovv is the distance set?
Distance can be set in four stages .
Fig . 157 C ontrol l ev er:
Sett in g d ista nce
Increasing distance
Pus h the slider switc h once to the rig ht 0 => fig. 157 . The
dista nce currently se t is shown for 3 seconds in the
instrument cluster d isp lay.
- Pu sh the s lider sw it c h
a gain to the right G) , to inc rease
the distanc e by o ne step.
Reducing distan ce
- Push the s lider switch once to the left Q . The distance
cur rently set is shown for 3 seconds in the instrument
cluster disp lay .
- Push the s lider switch
again to the left Q , to decrease
the d istance by one step.
The distance at which Adaptive Cruise Contro l fo llows a vehicle in
front is determined by
time intervals. A time int erval to a v ehicl e in
front is estab lished and maintained . This produces a speed -depen ­
dent interval. The higher the speed, the greater the saf ety interval in
feet (meters).
For example, if the interval
DI STA NCE 3 is set , a vehicle in front is
followed at a
time interval of 1.8 seconds .
Fo r a speed o f
50 mph (80 km /h ) this would be equivalent to a
distance of
1 3 1 feet (40 meters ) to the ve hicle in fron t.
The distances given here are nominal values . The vehicle speed may
exceed or fall short of these target speeds, depending on the
driving situation and the driving sty le of the v ehicle ahead.
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DISTANCE 1
Symbol c:::, _ c:::,_ --
Time interval 1 second
Dynamics Sporting
Distance at 25 mph (40 km/h) 36 Feet (11 Meters)
Distance at
50 mph (80 km/h) 72 Feet (22 Meters)
Distance at 75 mph (120 km/h) 108 Feet (33 Meters)
& WARNING
Following other vehicles too closely increases the risk of a crash
and serious personal injury .
• Following other vehicles too closely, particularly at higher
speeds increases the risk of collisions and serious personal injury .
• Setting short distances to the traffic ahead reduces the time
and distance available to bring your vehicle to a safe stop and
makes it even more necessary to pay close attention to traffic.
• Always select a speed and distance to traffic ahead that is safe
and appropriate under the prevailing traffic, road, weather and
lighting conditions.
• Never rely on the distance control feature of ACC alone to
prevent rear-end collisions. Always be prepared to brake and take
evasive action to avoid collisions 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 slow your vehicle safely .
If closing speed is too high, you must
apply the brakes yourself to reduce the risk of a rear-end crash.
• Always select a greater following distance to the vehicle ahead
on wet roads than on dry roads.
• Always read and heed the information and
WARNINGS ~ & in
"Description" on page 139.
Controls and equip ­
ment
DISTANCE 2 DISTANCE 3 DISTANCE 4
~ __ c:::, __ c:::,
___ c:::,_
c:::, ____ c:::,
1.3 seconds 1.8 seconds 2.3 seconds
Standard Standard Comfortable
46 Feet ( 14 Meters)
66 Feet (20 Meters) 82 Feet (25
Meters)
95 Feet (29 Meters) 131 Feet (40 Meters) 167 Feet (51 Meters)
197 Feet (60 Meters) 249 Feet (76 Meters)
[ i] Tips
• Distance can be adjusted using the slider switch on the lever and
through Adaptive Cruise Control in the MMI menu~ page
150. The
settings in the MMI menu are stored automatically and allocated to
the remote control key.
• If the distance was not set in the MMI menu Adaptive Cruise
Control , it is reset to the factory setting DISTANCE 3 when the igni­
tion is turned on. •
I • •

-Adaptive Crui se Control .._ _ ______,:,...._ _________________________________________ _
Driver information
App lies to veh icles: with Adapt ive Cruise Cont ro l
Displays in the instrument cluster
Depending on the driving situation, driver information is
displayed in the instrument cluster.
@ Primary display in the speedometer.
Fig. 158 Ove rv iew
instrument clu ste r
@ Supplementary display in the instrument c luster.
© Message in the instrument cluster display.
@ Prim ary display
Important information concerning vehic le operation with Adaptive
Cruise Control is shown in disp lay area @. T he desired speed yo u
set is highlighted in the speedometer and the warning lights show
whether adjustments are being made fo r an object ahead .
This information is always disp layed. Display area @is therefore
called the
primary display.
@ Supplementary disp lay
In display area@ infor mation fro m the navigation sys te m and the
trip computer is displayed in addition to information about Adaptive
Cruise Control. You can select among
the different information by repeated brief
t aps on the RESET b utto n on the w indshield wiper lever ~
page 40,
"Operation" .
P articularly on your first trips with Adaptive Cruise Control, the
supplementary display should be turned on.
@ Message
The information in area © is not d isp layed permanently. Informa ­
tion is displayed on ly if you change the time interva l, if there is a
malfunction or if the Adaptive Cruise Contro l is turned off. •
Applies to veh icles : w ith Adaptive Cruise Contro l
Primary display in the speedometer
Desir ed sp eed
Fig . 159 Primary
d is play in th e speed ­
omete r
The desired speed set by the driver is disp layed wi th a red LED .
The system al lows only speeds from 20 to 95 mph (30 to 150 km/h)
to be se t. This s peed range is fain tly i lluminated in the spee dometer.
Warning lights (symbols )
• ""c:::, Open road : Th e war ning lig ht ""c:::, sh ows that ACC is active
and that no moving vehicle has been detected with in range of the
ra dar senso r up ahead in yo ur l ane of travel. The se t speed is main -
tained. .,

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• "°" ""° D riv ing in traffi c: The warning light "°"""° shows that a
vehic le moving in your lane of travel has been de tected up front in
your lane of travel. Your speed is adjusted according to the speed of
the vehicle up front. ACC accelerates and brakes automatical ly
within the system's capabilities.
• "°" ""°
Reque st f or driver to a ssume control: The red flashing
warning light
G'.'.::> 1,.,<:Q means R equ est fo r d riv er to assume control.
You as the driver must slow the vehicle with the foot brake. The
symbo l "°""G'.'.::l tells you that the Adaptive Cruise Control is not able
to slow the vehicle down enough to keep a enough distance to the
vehicle in front of you . A warning tone signal wi ll also sound when
the symbol appears .
& WARNING
Improper use of the Adaptive Cruis e Control f eatures and inatten ­
ti on c an lead to an cra sh a nd s erio us per sonal injury .
• Never allo w the c losing speed between you and other v ehicles
to be so high t hat th e Adap tive Cru is e Control ma y not be abl e to
slow your vehi cle safel y. If closing speed i s too high , you must
apply the brake s yourself to r ed uc e the ri sk of a r ear-end cra sh .
• Alway s sele ct a greater follow ing di stance to th e vehi cle up
a he ad on w et ro ad s th an on dr y roa ds.
• Alway s read and he ed the inf ormation and WARNINGS~
& in
" De scription " on
pag e 139 .
[ i J Tips
• If the Adaptive Cruise Control initiates braking, the hydraulic
brake system is under pressure . Therefore, the brake peda l distance
is shorter and the pedal feels "harder".
• If you use the accelerator to go faster than the speed of the
vehicle ahead of you, the driver intervention prompt wi ll not be
accompanied by a warning tone.
• If the speed you previously set is exceeded, the indicator light in
the speedometer wi ll switch o ff.•
Con tro ls and eq uip­
ment
Ap plies to vehi cle s: wi th Ad apt ive Crui se Co ntro l
Display in the instrument cluster
You should hove the supplementary information
displayed here, p articularly on your first trips.
Fig. 160 D ispla y in th e
i n strum ent cl uste r
Scroll th rough the available information displays by briefly tapping
the ( RESET] button at the end of the windshield wiper lever . You can
se lect and information from the trip computer, naviga tion syste m or
Adaptive Cruise Control.
@ Veh icle symbol
@ Status
© Distance
@ V ehi cle sym bol
The vehicle symbol indicates whether the system has detected a
moving vehicle up front in your lane of travel.
• When no moving vehic le is detected up front, on ly the
outline of
the vehicle
is displayed.
• A
gra y vehicle will appear when a moving vehic le is detected up
ahead.
• A
red vehicle will appear i f the situation detected will soon lead
to a request for the driver to assume control. .,,_
Vehicle care I I irechnical data

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If Adaptive Cruise Control is turned off or no speed is set, no vehicle
is shown.
@ Status
• The text OFF appears in white letters when Adaptive Cruise
Control is turned off.
• The text
AVAILABLE appears in white letters when the system is
turned on but no requested speed has been set.
• The text
OVERRIDE appears in white letters when you exceed the
requested speed by accelerating.
• The text
DISTANCE! appears in red letters when the interval to a
vehic le traveling ahead is too short and you also have to slow your
vehicle with the foot brake.
• The text messages
DISTANCE 1, DISTANCE 2, DISTANCE 3 or
DISTANCE 4
appear in green letters to indicate the time interval
(distance) you have set and ACC is active.
© Distance
A pointer (arrow) is shown in this area. When slowly approaching a
moving vehicle detected ahead in your lane of travel, this pointer
represents the distance to that vehicle . When approaching that
vehicle rapidly, it serves as early warning of an impending request
for the driver to assume ful l vehicle control. The pointer moves on a
scale from right to left.
Open road: With an open road and no moving vehicle detected up
ahead, no pointer is shown.
Driving in traffic: If a vehicle traveling up ahead in your lane of travel
is detected, the pointer moves to the center area of the scale. This
area represents the time interval (distance) set. It is shown in
green
to make it easier to see.
Driver intervention prompt: Whenever the selected time interval
(distance) to the vehicle moving up ahead in your lane of travel is
less than the time interval (distance) set, the pointer moves into the
red area of the display. When the pointer reaches the farthest posi­
tion on the left, the driver intervention prompt is disp layed to indi -cate that the driver must now assume full vehicle control in order to
prevent
a collision. •
Applies to vehicles : with Adapt ive Cru ise Contro l
Messages
The text messages and symbols shown in this area of the
display are not displayed permanently.
Time intervals
Fig. 161 Information
line
The different symbols for the time intervals (distance) appear if you
change the settings=> fig. 161. In addition, there is a disp lay if the
gong (audible warning signal) is turned off.
Three white dots ... appear if a setting cannot be made with the
operating lever. The following are possible reasons
• If you pull the control lever forward to resume speed but no
requested speed was set.
• If you push the lever up to increase (or down to reduce) speed
when no speed has been set previously.
• If you push the lever up to increase (or down to reduce) speed
and this speed is outside the 20 to 95 mph (30 to 150 km/h) speed
range. .,