check engine AUDI S8 2008 Owner's Manual

Clear vision
Lights
Switching the headlights on and off -'t/-·
In the "AUTO" position, a light sensor automatically
s w itches t he head- and taillights on and off in respo nse to
l igh t con ditions.
Fig . 56 In stru ment
pan el: lig ht sw itch
Switching on automatic headlight control
- T urn th e light switch to AUTO => fig. 56 .
Switching on the side marker lights
- Turn the light switch to ~oo~.
Switching on th e headlights and high beam
- T urn t he light swi tch to io.
- Push the high beam leve r forw ard towards t he instru -
me nt panel
=> page 73 .
Switching off the lights
- T urn t he light switch to 0 .
Contro ls a nd eq uip­
ment
Clear vision
The head lights only work when the ignition is switched on . While
starting the engine or when switching off the ignition, the head ­
lights will go off and only the side marker lights will be on.
After starting the engine, the xenon headlights are automatically
adjus ted to the load and angle of the vehic le (for example, during
acceleration, braking) . This prevents oncoming traffic from experi ­
encing unnecessary headlig ht g lare from your xenon head ligh ts .
If the system is not operating properly, a warning symbol in the
Auto -Check Control is displayed
=> page 36.
With the side marker lights or head ligh ts switched on, the sym bol
next to the light switch illuminates
:oo: .
Daytime running lights
• USA models : The daytime running lights wi ll come on automati­
ca lly when the ig nition is turned on and the ligh t
switch=> fig. 56 is
in the
O position or the AUTO position (only in day light conditions).
The
Daytime running lights function can be turned on and off in the
MMI menu
Exterior lighti ng => page 70 => & .
• Canada models: The dayti me ru nn ing lights wi ll come on auto ­
matically when the ignition is turned on and the light switch
::::> fig. 56 is in the O position or the AUTO p o siti on (only in daylight
conditions)
=> & .
Automati c headligh t control
In the switch position AUTO the a utomatic headligh t cont rol is
turned on . The low beams are turned on automa tica lly through a
light sensor as soon as ambient brightness (e.g . when driving into a
tunnel) fa lls below a value preset at the factory . When ambient
brightness increases again, the low beams are turned off again
automatically =>& .
In the AUTO pos it ion the low beams are switched off automatically
when the ignition is turned off. If the high beams were switched on,
they w ill come o n again the next time the automatic head ligh t
~
Vehicle care I I irechnical data

ture on the windshield. The rain sensor wiper intervals depend on
t he sensitivi ty setting as well as vehic le speed . Dur ing brief s tops,
wiper motion wil l adjust in re lation to the amount of rain on the
windshield .
During br ief stops, e.g. at a red light, wiper mot ion wil l auto mati ­
ca lly be reduced to the next lower speed . Wipers a lready turning at
low speed. change to i nterm ittent w ip ing.
When the ignition is turned on, the washer jets are heated .
With the low beam headlights switched on, p ull the wiper lever
towards you only briefly to clean the windshield. Ho ld ing the w iper
lever wou ld a lso engage the headlight washer system each time you
clean the w inds hie ld and wou ld dra in t he washer flu id reservoir
pr ematurely .
& WARNING
• Wiper bl ade s are cruc ial for safe driving! Only when they are in
good condition are they able to clear the window s properly to
provide uncompromising visibilit y. Worn or damaged wiper blades
are a safety hazard
::::> page 82 , "In stalling new wiper blade s"!
• The rain sensor is only designed to a ssist and support the
driver . It r em ains entirely th e driver' s respon sibility to monitor
outside weather condit ions and to manually activate the wipers as
s oon a s rain or drizzle reduces visibility through the windshield.
• The windshield mu st not be treated with water-repellent mate ­
rials . They c an in crea se gl are under poor visibility condition s such
as wetness , darkness , or when the sun is low on the horizon. In
addition , they can cau se the wind shield wipers to chatter.
0 Note
In free zing or near freezing conditions:
• Always check that the wiper b lades are not frozen to the glass
be fore you turn the w ipe rs on. Loosen a wiper b lade w hich is frozen
Controls and equip­ ment
Clea r vision
in place before operating the wipers to prevent damage to the wiper
bl ade or the wiper motor.
• Do not use the wipers to clear a frosted window. Using the
wipers as a conve nien t ice scraper will des troy the wiper blades .
• Before you take your vehic le to an automatic car wash, make sure
you have the w inds hield w iper system switched o ff (lever in p osition
O), otherwise the windshield wiper system could get damaged in the
car was h if it should suddenly come o n.
[ i ] Tips
• Make sure the washer flu id reservo ir in the engine compartmen t
is topped off before going on a long trip . Look
up:::> page 323 for
check ing and f illing the washer conta iner.
• I f you sw itch off the ignition with the windshield wiper lever st ill
in the inte rval wi pe pos ition and t hen com e back a wh ile la ter a nd
drive off, the rain sensor wil l reactivate itself after the vehicle speed
has e xceeded 4 mph (6 km/h) .
• Worn or dirty windshie ld wiper b lades cause smearing which
ca n affect t he opera tion of the ra in senso r. Check the condi tion of
your windshield wiper b lades regu lar ly . •
Headlight washer system
The he adlight washer sy stem cle ans the he adlig h ts.
-Oper ate the win dshiel d w ip er/was her sy stem G) wit h th e
hea dlights t urned o n by ho ld ing th e l ever fo r lo nge r than
on e seco nd ::::.,
page 80, fig. 76.
The washe r jets extend f orward out of the fron t bumper dr iven by
water pressure to spray the front head lights with water .
You should inspect the head lights regu lar ly (for examp le when refu -
e ling) a nd c lean o ff any sol id dirt or i nsects from the lenses.
~

_________________________________________________ O_ n_ t_h _e _ ro_ a_d _ ___._
0 Note
If the warning/indicator light (U.S. models : BRAKE, Canadian models:
) flashes in the instrument cluster, there is a brake system
malfunction. By pressing the
I CHECK] button , you can bring up a
driv er m essage which explains the malfunction in more detail. If the
message
Parking brake! Please contact workshop appears, there is
a parking brake malfunction which you should have r epaired imme­
diately by an authorized
dealership => page 30. •
Cruise control
Switching the system on
The cruise control system makes it possible to drive at a
constant speed starting at 20 mph (30 km/h).
rr- -- ...--,,-~------ -~ ----,-~
Contro ls a nd eq uip­
ment
.... S? w ;f,
Fig . 149 Control lever
with set button Fig
. 150 Display:
Selected speed
Pull the lever © to position G) ~ fig. 149 to switch the
system on.
Drive at the speed you wish to set.
- Press button
® to set that speed.
The display => fig. 150 will show the set speed . The display may vary
depending on the type of display in your vehicle. The indicator light
CRUISE (US model)/ 0 (Canadian model) will also ligh t up in the
instrument cluster .
The speed is kept constant via an engine output adjustment or active brake intervention .
& WARNING
• Always pay attention to traffic even when the cruise control is
switched on. You are always responsible for your speed and the
distance between your vehicle and other vehicles.
• For safety reasons, the cruise control should not be used in the
city, in stop-and-go traffic, on twisting roads and when road condi­
tions are poor (such as ice, fog, gravel, heavy rain and hydro­
planing) -risk of accident.
• Turn off the cruise control temporarily when entering turn
lanes, highway exit lanes or in construction zones.
Vehicle care
I I irechnical data

___ A_ u_ t
_ o_ m_ a_ t_ i_ c _ t_r _a _n_ s_ m_ is_ s_io _ n ________________________________________________ _
The selector lever must be in Nor P. If one of the driving positions
is e ngaged a sa fe ty swit ch will preven t the eng ine from bei ng
started. See
also=:> pa ge 130 .
Before you move the selector lever from the P pos ition, you m ust
a lways apply the b ra ke pe dal be fore and wh ile depress in g th e
button in the hand le of the selecto r lever.
& WARNING
• Unintended vehicle movement can cause seriou s injury .
- When the selector lever is in a driving position , the vehicle
may creep , even at idle speed . Therefore do not release the
parking brake or foot brake until you are ready to move,
be cause power is tran smitted to the wheels as soon as a
driving position is engaged .
- Do not accelerate while select ing a driving position . At th is
time the engine must be at idle speed so that undue stress is
not placed on the clut ches in the transmi ssion .
- Remember: -even when stopped briefly with the automatic
transmission in
" D " or "R ", engine power is being transmitted
to the wheels . Your vehicle could "creep " forward or backward.
When stopped , keep the brake pedal fully depressed and use
the parking brake if necessary to keep the vehicle from rolling.
• If the selector lever is unintentionally moved into N while you
are driving , take your foot off the accelerator pedal and wait for
the engine to return to idle speed before sele cting a driving posi ­
tion.
• Never shift into
" R " or "P " when the vehicle is in mot ion .
• Never get out of the dri ver's seat when the engine is running .
• If you must get out of the vehicle , move the selector lever
securely into the P position and apply the parking brake firmly .
• If the engine must remain running , never have any driving posi ­
tion engaged when checking under the hood . Make sure the
selector lever has securely engaged and is locked in
"P" with the
parking brake firmly
set => page 299, "Engine compartment ".
& WARNING (continued )
Otherwise , any increase in engine speed may set the vehi cle in
motion , even with the parking brake applied . •
Selector lever positions
This sec tion des crib es the selec tor lever p ositions an d
driv ing rang es.
Fig . 184 Disp lay in the
in strument clu ster :
selector lever in pos i­
t ion D
T he sele cto r leve r posi tion engag ed ap pears next to the selector
l ever as we ll as in the instrument cluster disp lay . A lso, the current
gear engaged is show n in po sitions D and S .
P -Park
In this selector lever posit ion the t ra nsmi ssio n i s m ec hani cally
l ocked. Engage
P on ly when the vehicle is completely stopped=> &
i n "Dr iv ing th e auto mat ic tra nsmi ssion" on page 163 .
To shift in or out of position P , you must first press and hold the
b rake peda l
and then press the release button in th e selec tor leve r
handle wh ile movi ng the selector lever to or from
P . You can shift
ou t of this posi tion only wi th th e igni tio n on.
R -Reverse
Th e trans missi on wil l au to m atica lly select t he lowest gear ratio
when you shift into reverse .

llll.___l_n _t _e _ll _ig=- e_n _ t_ te_ c_h _n_ o_ lo...;g'"'-=- y ___________________________________________ _
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
vehicle remains operational and behaves in the same way as a
vehicle without EDL.
As soon as the brake has cooled down, EDL switches on again auto ­
matically.
& WARNING
• When accelerating on slippery surfaces, such as on ice or snow,
always be careful when depressing the accelerator pedal. Even
with the EDL working, the drive wheels can spin and reduce your ability to control your car. Risk of crash!
• The increased safety afforded by
EDL does not mean that you
can take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i] Tips
If a fault occurs in the ABS, the EDL is also not functioning. This is
indicated by the ABS warning
light => page 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
stabili zation program (ESP) . When the vehicle starts up and acceler­
ates, the wheels are prevented from spinning by adjusting the
engine power to match the amount of grip available from the road
surface.
How the system works
ASR performs automatically, i.e. without the driver's intervention.
With the aid of the ABS
sensors=> page 272, 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 should
occur in the ABS, the ASR will also be out of action.
& WARNING
The increased safety afforded by ASR does not mean that you can
take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i] Tips
To ensure that the ASR works properly, all four wheels must be fitted
with identical tires Any differences in rolling radius of the tires can
cause the system to reduce engine power when this is not desired.
See
also=> page 336, "New tires and replacing tires and wheels ".•
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The brakes on today's automobiles are still subject to wear,
depending largely on operating conditions and driving
habits=:,& .
On vehicles which are driven mostly in stop-and-go city traffic or
which are driven hard, the brake pads should be checked by your
authorized Audi dealer more often than specified in the
Warranty &
Maintenance booklet. _,,,

-Intelligent technology
P:V:1--------=-- --=-=-------------
& WARNING
• Never let the vehi cle roll to a stop with the engine shut off .
• If the brake boo ster i s not working, for example when towing
your vehicle , or because the brake booster has so mehow been
damaged, the brake pedal must be pres sed considerably harder to
make up for the la ck of booster as sistan ce . •
Functioning of Anti-Lock Brake System (ABS)
AB S pre vent s th e wh eels fr o m lo ckin g up un der braking .
The ABS contributes effective ly to ve hicle control s ince it prevents
th e whee ls from
lo cking w hen t he brakes are a ppl ied. This mea ns
that the vehicle remains steerable and is less likely to skid.
With ABS you do not need to pump the brake . Just hold the brake
pedal down.
H owever, do not expect the ABS to shorten braking distance under
all cir cum stances. W hen drivin g on g ravel o r on new ly fallen s now
on top of icy surfac es, bra king distance may be even longer, there ­
fo re, unde r th ese circum stances, i t is especially i mporta nt th a t yo u
drive slow ly and with great care .
How the ABS system works
An automatic check is made when a speed of about 4 mph (6 km/h)
is reac hed . When this ha p pens, a pumping n oise can be hea rd.
If an indiv idua l wheel begins to rotate too s lowly in relation to
vehic le speed and tends to lock, the ABS automatica lly reduces
brake pressure to prevent that whee l from loc king .
T his automat ic adjustment process wil l cause a
slight vibration of
th e br ak e pe dal a nd some noises to ale rt you th at ve hic le sp eed
must be adapted to existing road and traffic conditions.
& WARNING
Although the ABS is very effe ctive , always remember that braking
capability is limited by tire traction. Alway s adjust your driving
speed a ccording to the road and traffi c conditions . Do not let the
extra safety afforded by the ABS tempt you into taking extra risks.
The ABS cannot overcome the laws of physics.
[ i ] Tips
• I f ABS is not funct io ni ng properl y, a wa rn ing li ght will co me o n.
See ~ page 21.
• I f a fault occurs in the A BS, the EDL is also not functioning. This
i s indica ted by the ABS wa rn ing l igh t.•
Brake assistant
The brake assis tant is desig ned to ach ieve the o ptim um
brakin g eff ec t.
The br ake assistan t helps to in cr eas e the effec tive b raki ng pow er
and thus to achieve a shorter stopping distance . If the driver
p re sses the b rake pe dal very q uick ly, the brake assistan t auto mati ­
ca lly boosts the brakin g force to the maximum level, up to th e point
whe re the a nti-lock b rake functi on (AB S) int ervenes to sto p the
w hee ls from loc king . You s hou ld t hen k eep th e br ake pedal pressed
until t he vehicle ha s braked to the required speed . The brake a ssis ­
t ant s witches itse lf off as soo n as you re lease t he bra ke pedal.
T he b rake assistant will not be ope rative if there is a malfunction in
th e ABS .
& WARNING
Please remember that the accident risk always increases if you
drive too fast , especially in corners or on a slippery road , or if you
follow the vehicle ahead of you too closely . Increased risk of an
~

Intellig ent tec hnol ogy -
------------ -=--=-= '-
& WAR NIN G (c onti nued )
acc ident canno t b e co mp ensat ed for even b y th e br ake assis tant,
s o alway s maintain a safe sp eed . •
Servotronic® - advanced power
steering system
The power steering systems uses the power of the
running engine to allow precise s teering with little effor t.
The advanced Servotronic® power steering system senses the road
speed and electronically adjusts power assistance to provide
comfortab le and safe steer ing response exactly matched to the
vehic le speed.
Power s teeri ng will not work if the engine is off . As a result, the
steering whee l wil l be hard to turn .
The power steering fluid level is checked during the scheduled
maintenance serv ices.
0 Note
If there is an electron ic ma lfunction, servotronic will sti ll funct ion
like a conventiona l power steering system, providing a constant
steer ing suppor t force that is no longer proportionate to the vehicle
speed . This is most noticeable when turning the steering wheel at
low speeds (for examp le w hen parking), -more effor t wi ll be
required than usual.
• Be aware of the different than usua l steering response and
adjust your steering force accordingly .
• Have the problem checked and set right by an Aud i dea ler as
soon as possib le.
Controls and equip­ ment Safety first Vehicle operation
[
i ] Tip s
• When the engine is running, never hold the steer ing whee l
turned all the way to the right or to the left for longer than 15
seconds. The power steer ing pu mp wil l overheat the hydraul ic fluid
if you keep ho lding the steering whee l turned a ll the way. This is
like ly to damage the power steering system.
• I f the power steering system shou ld fail entire ly, or if the engine
is not runn ing ( for examp le, wh ile be ing towed), you w ill st ill be able
to steer the vehicle . However, considerably more effort will be
requ ired to do so.
• I f the power steering system shou ld have a leak, or is not func ­
tioning properly, contact your author ized Audi dealer im mediately.
• The power stee ring system requires a special ly formulated
hydrau lic fluid . The power steer ing reservo ir is the one located most
forward on the left side of the engine
compartment => page 308. The
correct flu id level in the reservo ir is important for proper func ­
tioning of the power steering. •
Driving with your quattro®
With All Wheel Drive, all four wheels are driven.
Genera l inf orm ati on
With All Whee l Drive, power is d istributed to all fo ur wheels. This
happens automatically depending on your driving style and the
road condi tions at the time . See
a lso => page 269, "Electronic differ ­
entia l lock ! EDU" .
Winter tires
When driving in the winter, your vehicle with All Wheel Drive has an
advantage, even with regular tires . In winter road conditions it may
be advisable to mount winter tires (or all-season tires) for improved
driveabi lity and braking: these ti res must be mounted on all four
wheel s. See
also=> page 341, "Winter tires". ~
Vehicle care Do-it-yourself service Technical data

lffll.___l_n _t _e _ll _ig=- e_n _ t_ te_ c_h _n_ o_ lo...;g'"'-=- y ___________________________________________ _
This notification reminds you that the starting capability of the
engine may be limited . As soon as you s tart d riv ing aga in, the
battery wi ll be recharged and the notification wi ll go out.
Driver notification appears and goes out again
If this driver notification appears after the ignition is turned on or
w hile dr iv ing and i t go es out again after a w hile, the ba ttery has
been adequately recharged.
Driver notification appears and does not go out again
If this driver notification appears after the ignition is turned on or
w hile driving a nd do es n ot go out aga in, t he bat te ry's state of
charge is not in the optimal range . Starting abi lity is restricted . Have
th e battery checke d as soon as p ossi ble at a deale rs h ip . •

____________________________________________________ T_r_a _i_l e_ r_t_ o _ w_ i
_ n...; g=- -•
Operating instructions
M ax im um tra iler weig ht
A trailer for your vehicle is limited to a typ ical c lass 1 or class 2
trailer.
T ra ile r l oad d is tributi on
Be sure the load in the trailer is he ld securely in place to prevent it
from shifting forward, backward or s ideways .
Never a llow a pass enger to r ide in a trailer:::::, & in "Driving instruc­
t ions" .
Engin e coo lin g sys te m
Tow ing a trai ler makes the engine work harder. It is important that
the cooling system's performance is up to the additiona l load. Make
sure that the coo ling system has enough fluid .
Tire press ure
When towing a trailer, inflate the tires of your veh icle to t he co ld tire
pressure listed under "Full load" on the labe l located either on the
driver's side B -pil lar (visible when the door is open) or inside the fuel
filler flap . Inflate trailer tires to trai ler and tire manufacturers' spec­
ifications.
L ig ht s
The head light settings should be checked wit h the trai ler attached
before driving off. Check to make sure both vehicle and trai ler lights
are working properly .
Safe ty c ha in s
Be s ure trailer safe ty chains are properly connected from the trailer
to the hitch on the vehicle. Leave enough slack in the chains to
permit turning corners . When yo u insta ll safety chains, make sure
they will not drag on the road when you are driving.
T he chains should cross under the trailer tongue to prevent it from
dropping in case of separat ion from the hitch.
Controls and equip­
ment Safety first
Vehicle operation
0 Note
If you are go ing to tow a trai ler, you must activate the tra iler opera­
tion
mode :::::, page 189, "Towing a Trailer". •
Driving instructions
Driving with a trailer always requires extra care and
consideration.
To obtain the best possib le handling of ve hicle and trailer,
p lease note t he following :
- Do not tow a loaded trailer when your car itself is not
loaded.
- Be especia lly careful whe n passing other vehic les .
- Observe speed limits .
- Do not drive at the maximum permiss ible speed .
- Always apply brakes early.
- Monitor t he temperature ga uge .
W eight d istr ibu tion
Towing a loaded trailer with an empty car results in a highly
unstable d istribution of weight. If this cannot be avoided, drive at
very low speeds only to avoid the risk of losing steering control.
A "balanced" rig is easier to operate and control. This means that
t he tow vehicle should be loaded to the extent possible and permis ­
sib le, while keeping the trailer as light as possib le under the circum ­
stances . Whenever possible, transfer some cargo to the luggage
compartment of the tow vehicle whi le observing tongue load
requirements and vehicle loading considera tions .
.,,.
Vehicle care Do-it-yourself service Technical data

_____________________________________________ C_ l_ e _a_ n_ in~ g_a
_ n_d_ p_ r_ o_ t
_ e_ c_t _io _ n __ fflll
•
from fading . Slight color variations will develop in normal use and
are not an indication of material deterioration.
0 Note
• Never use chemical solvents (e.g. lighter fluid, turpentine),
waxes, shoe polish or similar products on Alcantara® surfaces.
• To avoid damage, have stubborn stains removed by a commer­
cial cleaning specialist.
• Do not use brushes, stiff sponges or similarly abrasive cleaning
aids. •
Safety belts
Only well-maintained safety belts work reliably when
needed.
- Keep belts clean.
- For cleaning, use a mild soap and water solution. Let
belts dry thoroughly and away from direct sunlight.
- Do not allow inertia reel safety belts to retract before
they are completely dry.
- Check the condition of your safety belts
regularly.
Heavily soiled safety belts may not retract properly.
& WARNING
Damaged safety belts can break in a crash.
• Anything that might damage your safety belts could mean that
you and your passengers would not be adequately protected in an
accident.
• Safety belt performance depends on correct installation. Never
remove belts from the vehicle to clean them.
&, WARNING (continued)
• Do not use chemical cleaning agents, bleach or dyes. They have
corrosive properties which weaken the webbing.
• When cleaning your safety belts, inspect them for damage. If
you discover damage, see your Audi dealer.
• Always read and heed all WARNINGS and other information
=> page 288. •
Engine compartment
Be especially careful when cleaning the engine compart­
ment.
Always switch off the ignition before cleaning the engine => &,.
Plenum panel
Remove leaves from the plenum panel in front of the windshield
under the engine hood. This prevents the water drain holes from
becoming blocked, and it prevents debris from entering the vehicle
interior through the heating and ventilation ducts.
Corrosion protection
The engine compartment and transmission have been corrosion­
protected at the factory.
Good anti-corrosion treatment is very important, particularly in the
winter. If the vehicle is frequently driven on salt treated roads, the
entire engine compartment and plenum panel should be thor­
oughly cleaned at the end of winter and retreated to prevent salt
damage. At the same time, the underside of the vehicle should be
washed as well.
If the engine compartment is cleaned at any time with grease
removing solutions
11 , or if you have the engine washed, the anti­
corrosion treatment is almost always removed as well. It is therefore .,_
11 Use only the correct cleaning solut ions. Never use gasoline or diesel fuel.
Vehicle care