AUDI S8 2010 Owners Manual

Checking and filling ------------------------------- ---=.:..:..=.:=~..:::..:.....:..:.;__ ___ _::,______,.J
& WARNING (co ntinued )
• Antifreeze is pois onous. Alway s store antifreeze in its original
container and well out of the r each of children.
• If you drain the coolant , it must be caught and safely stored in
a proper container clearly marked "poi son ".
0 Note
• Coolant poll utes the environment and could cause an engine fire .
Excess coolant w ill be forced out throug h the pressure re lief valve in
t he cap when the e ng ine becomes hot .
• If, in an emergency, o nly wate r ca n be adde d, the correct ratio
between water and antifreeze=>
page 296 must be restored as soon
as possib le.
W For the sake of the environment
Dra ined coolant shou ld not be reused. A lways dispose of used coo lant
w hile observ ing a ll enviro nment al regul ations . •
Radiator fan
The radiator fan switches on automatically by itself
T he radi ator fa n is d riven by the engine via th e V-bel t. The v iscous
clutch regu lates the speed of the fan accord ing to the temperature of
t he coolant.
An auxiliary e lectr ic rad iator fan* sw itches on and off depend ing o n
coo la nt tempe rat ur e and othe r vehicle ope ra ting condi tions .
After you switch the engi ne off, the auxilia ry fa n can cont inue r unning
for up to 10 minutes - even w ith the ignition off . It can even switch on
agai n lat er by itse lf => & , if
• the tempe rature of the e ngine coolant rises due to the heat build ­
up from the eng ine in t he engi ne comp art ment, or
Vehicle OP-eration
• the engine compartment heats up because the veh icle is parked in
in tense s unlight.
& WARNING
• To reduce the ri sk of personal injury never touch the radiator
fan.
• The auxiliary electri c fan is temperature controlled and can
switch on suddenly even when the engine is not running .
• The auxiliary radiator fan switches on automatically when the
engine coolant reaches a certain temperature and will cont inue to
run until the coolant temperature drops .•
Brake fluid
Checking brake fluid level
T h e b rake fluid l evel can be ch ecked with a quick glance.
-w ;:;
Fig. 24 8 En gine
compa rtme nt: Brak e
f luid re se rv oi r
Be fore you chec k anyt hin g in the engine compartment,
always read and heed all WARNINGS~ & in "Working in
t h e engine compartm ent" on
page 289 . .,_
Vehicle care Do-it-yourselt service iTechnical data

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- Read the brake fluid level from the brake fluid reservoir
=> fig. 248 . T he brake fluid level mus t be between the
" M IN" and "MAX" markings.
The br ake fl uid re se rvoir is loc ated at the rear pa rt iti on of the engine
compartment on the left side~ page 290.
T he f lu id level may drop slightly after some time due to the auto­
matic adjus tment of t he b rake pads. This is not caus e for alarm.
If the brake flu id leve l falls considerably below the "MIN" mark, t he
br ak e wa rning/ind ic ator lig ht ( U.S . model s:
BRAKE , Can adi an mod els:
«D> ) will come on~ page 20 and~ page 28. Do not continue to
operate the vehicle . The comple te brake system sho uld be thoro ughly
checked by an author ized A udi dealer or ot her qualified facility and
t he ca use correcte d. If the b rake fl uid leve l is too low, the bra ke
wa rning/in dicator light will illu mi nate . Con tact an au thorized Aud i
dealer
immediately .•
Changing brake fluid
H ave the brake flui d changed by an ex perienc ed techni­
cian.
Brake flui d abso rbs mois ture from t he a ir . If t he wa ter con ten t in the
brake fl uid is too hig h, corros io n in the b rake system may res ult afte r
a period of time . The boiling po int o f the bra ke fl uid will also decrease
cons iderab ly and decrease brak ing perfo rmance.
The refore, the brake fl uid m ust be changed
every two years . Always
use new bra ke fluid w hich conforms to Fede ral Motor Veh icle St an­
dard "FMVSS 116 DOT 4" .
Th e b rake fl uid reservoi r ca n be diffi cult to rea ch, there fore, we
recommend that you have the bra ke fluid c hanged by your author ized
Audi dealer. Your dea ler has the correct tools, the right b rake fl uid
and the know-how to do t his for you .
& WARNING
• Brake fluid is poisonous. It must be stored only in the closed
original container out of the reach of children!
• Brake failure can result from old or inappropriate brake flu id.
Observe these pre cautions:
- Use only brake fluid that meets SAE specification
J 1703 and
conforms to Federal Motor Vehicle Standard 116. Always che ck
with your authorized Audi dealer to make sure you are us ing
the correct brake fluid. The correct type of brake fluid i s also
indicated on the brake fluid reservoir .
- The brake fluid must be new. Heavy use of the brakes can
cause a vapor lock if the brake fluid is left in the system too
long . Thi s can seriously affect the efficiency of the brakes as
well as your safety . This could result in an accident.
0 Note
Brake fluid will damage the paint of your ve hicle .
~ For the sake of the environment
Because of the prob lem of proper disposal of brake fl uid as we ll as
the spec ia l too ls req uired and the necessary expe rtise, we recom ­
m en d that you have t he brake fl uid changed by your autho rized Audi
dea ler .•
Battery
General information
Under normal operat ing condit ions, the battery in your Aud i does not
nee d any m ain ten ance. Wi th high outs ide temper atures o r long d aily
dr ives we recommend that yo u have the elect rolyte level checked by .,_

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a service facility . The electrolyte level should also be checked each
time the battery is charged =>
page 303.
Have the batte ry checked when you take your vehicle in for serv ice .
You are well advised to rep lace a battery that is older than 5 years.
With certa in types of a irbag deployment, the ba ttery is disconnected
from the vehicle electrical system for safety reasons=>
& in "Repair,
care and disposal of the airbags" on
page 220.
Di sconne cting th e bat tery t ermina ls
Some vehicle f unct ions (power window regulators, fo r example) are
lost if the battery termina ls are disconnected . These functions have
to be re learned after the battery termina ls are connected aga in. To
prevent this, t he battery should only be disconnected from the
vehicle e lectr ica l system when absol ute ly necessary for repairs.
Vehicles not driven for long periods
If you do no t dr ive your veh icle over a period of severa l days or weeks,
electrical components are gradually cut back or switched off. Th is
red uces e nergy consumption and main tains sta rt ing capabili ty ove r a
longer period=>
page 258.
Be aware that when you unlock your vehicle, some of the convenience
functions may not operate, such as the Convenience key*, the remote
control or the power seat adjustment. The convenience functions will
be availab le aga in whe n you tur n on th e ignition and start the eng ine.
Winter operation
Dur ing the winter months, battery capac ity tends to decrease as
temperatures drop. This is because more power is also consumed
while starting, and the headlights, rear w indow defogger, etc., a re
used more often.
Avoid unnecessa ry power consum ption, part ic ula rly i n city traffic o r
when traveling only short distances. Let your authorized Audi dealer check the capacity of the vehicle battery before w inter sets in
=>
page 303 . A well charged battery will not only prevent start ing
prob lems when the wea ther is cold, but will also las t longe r.
Vehicle OP-eration
(I) Tips
If your vehicle is left standing fo r seve ral weeks at extremely low
temperatures, the vehicle battery should be removed and stored
w here it will not free ze. This will preven t it from being damaged and
having to be replaced. •
Working on the battery
Be especially careful when working on or near the
battery.
Vehicle care
Fi g. 2 49 Lugga ge
co mp artme nt: Righ t·
s ide stor age co mpar t·
me nt
Fig. 25 0 Lug gage
comp art me nt: Batt ery ~
Do-it-yourselt service iTechnical data

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The battery is located in the luggage compa rtment on the
right side beh ind a cover. Before you check anything in the
luggage compa rtmen t, read and heed all WARNINGS=>& .
- To open the side sto rag e com part me nt, turn the tw o pins
@ =>fig . 24 9 to th e vert ical position .
The positive( +) battery termina l is p rotected by a plastic cov er. This
cover must be removed to access the positive( +) terminal when
c onnect ing jumpe r cab les to sta rt the engine.
Always heed the safety warnings, when working on the vehicle
bat tery or the vehicle e lect ric al system to p revent injury .
The following WARNINGS are very important when
working on the battery:
Always heed the following WARNING SYMBOLS and safety pre­ cautions when working on the battery.
-
®
Always wear eye protection.
Battery acid contain s sulfuric acid. Always wear
gloves and eye protection .
No
- sparks
- flames
- smoking .
When a battery is charged, it p roduces hydrogen
gas which is explosive and could cause personal
injury .
Always keep the battery well out of reach of chil­
dren .
& WARNING
Whenever working on the battery or on the electrical system,
there i s the ri sk of injury, a ccident and even fire. Read and heed
the following WARNINGS:
• Alway s wear eye protection . Do not let batt ery acid or any lead
part icles get on your skin or clothing. Shie ld your eyes. Explosive
ga se s can cause blindnes s or other in jury.
• Battery acid contains sulfuric acid. Sulfuric acid can cause
blindne ss and severe burns .
- Always wear gloves and eye protection . Do not tilt the
battery becau se acid could leak out of the ventilation open­
i ngs.
- If you get battery acid in your eyes or on your skin, immedi­
a tely rinse with cold water for several minutes and get medical
attention .
- If you should ingest any battery acid , see k medical attention
immediately.
• Do not expose the battery to an open flame, elect ric sparks or
an open light .
• Do not smoke.
• Do not interchange the positive and negative cables.
• When working on the battery, be sure not to short-circuit the
term inals with tools or other metal objects. This would cause the
battery to heat up very quickly, which could lead to damage or
e x plos ion and personal injury.
• When a battery is charged, it produce s hydrogen ga s wh ich is
e xplos ive and could cause pe rsonal inju ry.
• Alway s keep the battery well out of the reach of children .
• Before work is done on the ele ctrical system , disconnect the
negative ground cable.
• Before performing any work on the electrical sy stem , switch
off the engine and ignition as well as any electrical equipment.
The negative cable on the battery mu st be disconnected. If you are
~

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& WARNING (co ntinued )
just going to replace a light bulb , then it is enough to switch off
the lights .
• Before disconnecting the battery , switch off the anti-theft
alarm system! Otherwise you will set off the alarm.
• When disconne cting the battery, first disconnect the negat ive
cable and then the po sitive cable.
• Before reconnecting the b attery, make sure all electrical
consumer s are sw itched off. Reconnect the positiv e cable fir st and
then the negative cable . Never inte rchange the cables -this could
start a fire!
• Never charge a frozen or a thawed-out battery.
It could
explode! If a battery has frozen, then it must be replaced . A
di scharged batter y can freeze over at 32 °F (0 °C ).
• Make sure the vent hose is always attached to the opening on
the side of the battery .
• Never use batteries which are damaged. There is the danger of
an explosion! Alway s replace a damaged battery.
& WARNING
California Proposition 65 Warning:
• Battery posts , terminal s and related accessories contain lead
and lead compounds, chemicals known to the State of California
to cause cancer and reproductive problems. Wash hands after
handling.
0 Note
• Do not disconnec t the vehicle batte ry when t he ignit ion is
switched on o r when the engine is running, otherwise, you will
d amage e le ctro nic c ompone nts in t he ele ctrica l sys tem.
Safety first
• If your ve hicle is go ing to sta nd for a long per iod of time w it h out
bein g driven, protec t th e battery fro m "freezi ng", o therw ise i t wi ll be
damaged and will then have to be replaced .•
Battery charging
Sta rting t he e ng in e req uires a well c harged battery.
Always read and heed all WARNINGS b elo w =:> & and=:> &
i n "W orki ng on t he batt ery" o n
page 3 01.
- Turn off th e igni tio n and all electr ica l co nsum ers.
- Make su re the area is well vent ilated w hen you charge the
batte ry .
- Attach the red (posi tive
(B) c la m p of the charging equip­
me nt to the posit ive te rmin al o f th e bat tery and t he b lac k
( n eg at ive(:)) clam p to t he jumper term inal.
- Only now plug t he m ain s lead for the c harg ing e quip ment
i n to t he wa ll outlet a nd tu rn it on=:> &.
- Make sure the charging rate is not over 30 amps/14.8
Volt.
- When the b attery is fully c harg ed: Turn t he ch arging
equ ip m ent off and remo ve t he mains l ead fr om the wall
ou tlet.
- Now remove the clamp s for the cha rging eq uipment .
A discharged ba ttery can freeze a t temperat ures of on ly O 0C. Allow a
frozen batte ry to thaw comp letely before attempting to charge it
=> & . However, we recomme nd not usin g a thawed battery aga in
because the battery casing can be cracke d due to ice formation and
c a n l eak battery a cid. .,._
Vehicle care Technical data

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Battery charging (Maximum charging rate of 30
amps/14.8 Volt )
When charging at /ow voltages (e.g . w ith a trickle charger ), th e
battery cab les do not have to be disconnected first. The batte ry caps
should
not be opened when cha rging a ba ttery .
It is not necessary to remove the battery from the luggage compart­
ment, and i t is also no t ne cess ary to dis connect the cables.
Fast charging the battery (charging rate above 14.8
Volts)
For technical reasons do not use a battery cha rger that uses voltage
grea te r t han 14 .8 Vol ts to ch arge yo ur vehicle's ba tte ry .
& WARNING
Charging a battery can be dangerou s.
• Always follow the operating instructions provided by the
battery charger manufacturer when charging your battery .
• Never charge a frozen battery . It may explode be cause of g as
trapped in the ice . Allow a frozen battery to thaw out first.
• Do not reu se batteries which were frozen . The battery h ousing
may have cracked and weakened when the battery froze.
• Charge the battery in a well ventilated area. Keep away from
open flame o r elect rical spark. Do not smoke. Hydrogen gas gener ­
ated by the battery i s explosive.
• To reduce the danger of e xplosion , never connect or disconnect
c harger cable s while the charger is operating.
• Fast charg ing a battery is dangerous and should only be
attempted by a competent technician with the proper equipment .
• Battery acid that may spill during charging should be wa shed
off with a so lution of warm water and baking soda to neutralize
the acid.
0 Note
N ever use a fast cha rger as a booster to s tart the eng ine. This w ill seri­
ously damage sensitive e lectronic components , such as control units,
re lays, ra dio, etc., as well as t he ba ttery cha rger. •
Battery replacement
The new battery must have the s ame specifications and
dim ensions as the original equipment b atte ry.
Inte lligent e nergy ma nagement in yo ur vehicle is responsib le for
distr ibuting the elect rical energy throughout your vehicle
~ page 258. T he intelligent energy management sys tem will keep
the eng ine battery charged better than vehicles without this system .
T o m ake s ure the addi tional e lectr ic al energy is available o nce aga in
after you have changed the battery, we recommend that you install
b atter ies of the same type and manuf actur e only ( the same as t hose
installed at the t ime you r vehi cle was delive red) . Specifications are
liste d on the ba ttery ho using. Your a uthorized Audi dealer w ill then
code the battery management control unit.
Th e new batte ry must have the same capacity, volta ge (12 vo lts),
ampe rage, const ruct io n and p lug sealing .
When installing the battery, make s ure the ign ition and all electrical
c ons umers are turned off.
0 Note
Mak e sure the vent ilat io n hose o n the side o f th e battery is
connec ted, otherwise fumes or battery acid can leak o ut.
<£> For the sake of the environment
Because of the prob lem of proper disposal of a ba ttery, we recom­
mend you r auth o rized Audi dealer change the ba ttery for you.
Ba tte ries con tain sulfu ric acid and lead and must a lways be disp osed
~

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of properly in compliance with all environmental regulations .
Disposing of vehicle batter ies improperly is
very dangerous to the
environment .•
Windshield/headlight washer
container
F ig . 251 E ngine
compa rtme nt: W ind·
sh iel d and h eadlight
w asher flu id con tainer
The washer fluid container is marked wi th the symbol ~ on
its cap.
- Before you check anything in the engine compartment,
always read and heed all WARNINGS~ & in "Working
in the engine compartment" on page
289.
- Lift the filler cap tongue to add washer fluid. You can fill
the container to the top.
- Press the cap back onto the filler neck a fter filling the
container.
You can find the reservoir capacity i n the table in~ page 360 .
To p revent lime residue from bui ld in g up on the spray jets, use
distilled wate r when refilling . Always add a glass cleaner solution
(with frost p rotection in the winter) .
Vehicle OP-eration
0 Note
Do not mix engine coo lant antifreeze o r any other additives to fill up
the w indshield wash er reservoir .•
Vehicle care Do-it-yourselt service iTechnical data

-~_T_ i_ re _ s_ a_n _ d_ w_ h _e_ e_ ls _________________________________________________ _
Tires and wheels
Tires
General notes
Tires may be the least appreciated and most abused
parts of a motor vehicle.
T ir es may be the least apprec iated and most abused pa rts of a moto r
vehicle. Tires are, however, one of the most important parts of a
veh icle, parti cularly conside ring the comparative ly small patch of
rubber on eac h tire that assu res that all- important co ntact between
you , your ve hicle and the road .
Ma inta in ing t he correct t ire pressu re, making s ure that your veh icle
and i ts tires do not have to carry more weight than they can safely
hand le, avoid ing damage from road ha za rds and reg ula rly inspect ing
tires for damage incl ud ing c uts, s lashes irregular wea r and overall
condi tion are the mos t important th ings that you can do to help avoi d
sudden tire fa ilure includ ing t read separation and blowouts .
Avoiding damage
If you have to drive over a curb or sim ilar obstacle, drive very s lowly
and as close as poss ible at a right angle to the cu rb .
Always keep chemicals including grease, oil , gasoline and bra ke fl uid
o ff the t ires .
Inspect the ti res regularly for damage (cuts, crac ks o r bl ist ers, e tc .).
Remove any foreign bodies embed ded in the trea ds.
Storing tires
M ar k tires when yo u remove t hem to indica te the d irect ion of rota ­
tion . This ens ures yo u to be able to mo unt them co rrectly whe n you
re insta ll them.
Wh en r emoved, t he wheels or tires s hould be sto red in a c ool, dry and
preferably da rk p lace. Sto
re tires in a ver tica l pos it ion if they a re not mounted on rims, in a
hor izonta l position if they are mo unted on r ims.
New tires
N ew tires have to be bro ken in~ & .
Th e tread dep th of new tires may v ary, ac cor ding to t he type an d
make of t ire and the tread pattern.
Hidden damage
Dama ge to t ires and rims is often not readi ly visible . If yo u notice
unusu al v ib rat ion o r the veh icle pulls to one sid e, t his may i ndicate
that one of the tires has been damaged. The tires must be c hecke d
i m medi ately by an a uthor ized A udi deale r or quali fied w or ksh op .
Unidirectional tires
A u nidirectional tire can be identified by arrows on the sidewall, that
point in the d irect io n the tire is des igned to rotate. Yo u m ust follow
t he s peci fied dire ction of ro tation . T his is nece ssary so th at t hese
tires can develop the ir optimum c haracter istics regarding gr ip, road
noise, we ar and hy dropl aning res istance. For more informa tion
~page 341 .
& WARNING
New tires or tires that are old , worn or damaged cannot provide
maximum control and braking ability.
• New tires tend to be slippery and must be broken in. To reduce
the risk of losing control, a collision and serious personal injuries, drive with special care for the first 350 miles (560 km) .
• Driving with worn or damaged tires can lead to loss of control,
sudden tire failure , including a blowout and sudden deflation ,
crashes and serious personal injuries. Have worn or damaged tires
replaced immediately. .,_

________________________________________________ T_i_re _ s_ a _ n_d_ w_ h_ e_ e_l_s __ l!'II
& WARNING (co ntinued )
• Tires age even if they are not be ing used and can fail suddenly ,
e specially at high speeds . Tires that are more than 6 year s old can
only be used in an emergency and then with special care and at low
s peed .
Glossary of tire and loading terminology
Accessory weight
means the combined weigh t (in excess of those sta ndard items wh ich
may be replaced) of automatic transmission, power steer ing, power
bra kes, powe r win dows, power sea ts, radio, and heate r, to the exte nt
that these items are available as factory-insta lled equipment
(whet her i ns ta lled or no t).
Aspect ratio
means the r atio of t he he ight to t he widt h of the t ire in percent.
N umbers of 55 or lower indicate a low sidewa ll for improved steer ing
res ponse and bet ter over all h andling on dry p avemen t.
Bead
means the part of the t ire that is made of stee l wi res, w rapped or
re in forced by ply cords and that is shaped to fit the rim.
Bead separation
means a brea kdown of the bond between components in the bead.
Cord
means the st rands forming the plies in the ti re.
Safety first
& W ARNING (co ntinued )
• Never mount u sed tires on your vehicle if you are not sure of
their "previous history ." Old u sed tires may have been damaged
eventhoughthedamagecannotbeseenthatcanleadtosudden
tire failure and loss of vehicle control.
• If you notice unusual vibr ation or if the vehicle pulls to one side
when driving, always stop as soon as it is safe to do so and check
the wheels and tires for damage. •
Cold tire inflation pressure
means the t ire pressu re recom mended by the vehicle manufa ctu rer
for a tire of a desig nate d size that has not been driven for more than
a couple of m iles ( kilomete rs) a t low speeds in the t hree hour per io d
before the tire pressu re is measured or adjusted.
Curb weight
means the weight of a moto r vehicle wit h standard equipment
incl uding the max imum ca pac it y of fue l, o il, and coo lan t, air condi ­
tioning and additiona l weig ht of optional eq uipment.
Extra load tire
means a tire design to operate at higher loads and at higher inflat ion
pressures than t he co rresponding sta ndard t ire. Extra load tires may
be identif ied as "XL", "xl", "EXTRA LOAD", or "RF" on the sidewa ll.
Gross Axle Weight Rating ( "GAWR ")
means the loa d-carrying capac ity of a sing le ax le system, measure d at
the t ire-grou nd interfaces.
Gross Vehicle Weight Rating ("GVWR")
mea ns the maximum tota l loaded we ig ht of the vehicle .
Vehicle care Technical data

-~_T_ i_ re _ s_ a_n _ d_ w_ h _e_ e_ ls _________________________________________________ _
Groove
means the space between two adjacent tread ribs.
Load rating (code)
means the maximum load that a tire is rated to carry for a given infla­
tion pressure. You may not find this information on all tires because
it is not required by law.
Maximum load rating
means the load rating fo r a tir e at the maximum permissible inflation
pressure for that tire.
Maximum loaded vehicle weight
means the sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight, and
(d) Production options weight
Maximum (permissible) inflation pressure
means the maximum cold inflation pressure to which a tire may be
inflated. Also called "maximum inflation pressure."
Normal occupant weight
means 150 lbs. (68 kilograms) times the number of occupants seated
in the vehicle up to the total seating capacity of your vehicle.
Occupant distribution
means distr ibution of occupants in a vehicle .
Outer diameter
means the overall diameter of an inflated new tire.
Overall width
means the linear distance between the exteriors of the sidewalls of
an inflated tire, including elevations due to labeling, decorations, or
protective bands or ribs.
Ply
means a layer of rubber -coated paralle l cords.
Production options weight
means the combined weight of those installed regular production
options weigh ing over 5 lbs. (2.3 kg) in excess of those standard
items which they replace, not previously considered in curb weight or
accessory weight, including heavy duty brakes, ride levelers, roof
rack, heavy duty battery, and special trim.
Radial ply tire
means a pneumatic tire in which the ply cords that extend to the
beads are laid at substantially 90 degrees to the centerline of the
tread .
Recommended inflation pressure
see=> page 307, "Cold tire inflation pressure".
Reinforced tire
means a tire design to operate at higher loads and at higher inflation
pressures than the corresponding standard tire. Reinforced t ires may
be identified as "XL ", "x l", "EXTRA LOAD", or "RF" on the sidewall.
Rim
means a metal support for a tire or a tire and tube assembly upon
wh ich the tire beads are seated .
Rim diameter
means nominal diameter of the bead seat . If you change your wheel
size, you w ill have to purchase new tires to match the new rim diam­
eter .
Rim size designation
means rim diameter and width.
Rim width
means nom inal distance between rim flanges.