2012 AUDI S8 battery

192 Intelligent technology
be advisable to mount winter tires (or all-sea­
son ti res) for improved driveability and brak­
ing: these t ires must be mounted on
all four
w heels .
See also c> page 250, Winter tires.
Snow chains
Where snow cha ins are mandatory on certa in
roads, this normally a lso applies to vehicles
with A ll Wheel Driver=:>
page 251, Snow
chains.
Replacing wheels /t ire s
Vehicles w it h All Wheel Dr ive must always
have tires of the same size . Also avoid tires
with different tread depths. For details see
page
c> page 246, New tires and replacing
tires and wheels.
Off-Road driv ing?
Your Audi does not have enough ground clear ­
ance to be used as an off -road vehicle.
It is
therefore best to avoid rough tracks and un ­
even terrain as much as possible. Also refe r to
i=>page 195.
A WARNING
Always adjust your driving to road and traf­
fic condit ions. Do not let the extra safety
afforded by All Whee l Drive tempt you into
taking extra risks.
-Although the All Whee l Drive is very ef­
fective, a lways remember that b raking
capacity is limited by t ire traction. You
should the refore not dr ive at excessive
speeds on icy or slippery road su rf a ces.
- On wet road su rfaces, be careful not to
dr ive t oo fast becau se t he front wheels
co uld beg in to s lide on top of the wa ter
(aquaplaning) .
If this should occ ur, you
wi ll have no warning from a sudden in­
crease in engine speed as with a front­
wheel drive vehicle. A lways drive at
speeds wh ic h are suited to the road con­
ditions -risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimizes the
availability of electrical energy for starting the engine.
If a vehicle with a conventiona l energy system
is not driven for a long per iod of t ime, t he bat­
te ry is discharged by idling current consume rs
(e.g. immobili ze r). In certa in circumstan ces it
ca n res ult in the re be ing insufficien t energy
available to start the eng ine.
Intelligent energy management in your vehi­
cl e ha ndles the dist rib ution o f electr ica l ene r­
gy. Start ing abili ty is m arkedly improved and
the life of the battery is extended .
Bas ica lly, energy management consists of
batt ery diagnosis , idling current manage­
ment
and dynamic energy management .
Battery diagnosis
Battery diagnosis continuously determines
the state of the batte ry. Sensors determine
batte ry voltage, battery cu rr e nt and battery
tempe ratu re. This de termines the cur ren t
state o f cha rge and t he power o f th e battery.
Idling current management
Idli ng current management reduces energy
consumpt ion while the vehicle is standing.
With the ig nition sw itched off, it controls the
energy supp ly to the variou s ele ctri ca l compo ­
nen ts. Da ta from ba ttery d iagnos is is co nsid­
ered.
Depend ing on the batte ry's state of cha rge,
i ndivid ual con sume rs a re g radually turned off
to prevent excessive discharge o f the battery
and th us main tain starting capabi lity.
Dynamic energy management
While the vehicle is being d riven, dynamic en­
ergy ma nagement distr ib utes the energy ge n­
era ted a ccord ing to t he needs of the individ u-
al components.
It r egula tes consumption, so
t h at more e lectrical energy is not being used ..,.

than is being generated and ensures an opti­mal state of charge for the battery.
@ Tips
- But even energy management cannot
negate the limits o f physics. Consider
that the power and life of a battery are
li mited.
- If starting ab ility is threatened, the indi­
cator light
(•i appears ~ page 16, 0
Battery.
What you should know
The highest priority is given to maintaining
starting capability.
The battery is severely taxed in short-dis tance
d riving, in city traffic and during the co ld time
of year . Abundant e lectrica l energy is re­
q ui red, but only a litt le is generated. It is also
cr itical if the engine is not runn ing and electri­
cal components are turned on. In th is in­
stance energy is being consumed but none is
be ing generated .
It is in precisely these situations that you w ill
notice energy management actively regulat­
i ng the distribution of energy.
Vehicle sta nds for an ext ended p eriod
If you do not drive you r vehicle over a period
of several days or weeks, electrical compo­ nents are grad ually cut back or switched
off .
This reduces energy consumption and main­
tains sta rting capab ility over a longer per iod.
Some of the conven ience f unctions may not
ope rate, such as the inter ior lig hts or the
power sea t adjustment. The conven ien ce
f u nctions w ill be ava ilable again when you
switch on the ignit ion and start the engine .
With the engine turned off
If you listen to the radio, for example, with
the engine turned
off or use other MMI func­
tions, the battery is being discharged .
If starting capability is jeopa rdized due to en­
ergy consumpt ion, the fo ll ow ing warning ap­
pears in the MMI display :
Intellig ent technolog y 193
Plea se start the engine soon or the sy stem
will be turned off .
The wa rni ng ind ic ates that the system wi ll be
tu rned
off automatically a fter 3 minu tes. If
you w ish to continue using the funct ions, yo u
have to start the engine.
With the engine running
Althoug h elec trical energy is generated when
t h e ve hicl e is being driven, t he battery can be­
come d ischarged. This happe ns mostly when
little energy is being generated and a great
deal consumed and the battery's state of
charge is not opt imal.
T o b ring the energy ba lance back in to equili ­
brium, consumers which require especially
l a rge amounts of energy a re temporari ly cut
back or sw itched
off. Heat ing systems in par­
ticular require a great deal of energy. If you notice, for example, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched
off . These systems w ill be available again as
soon as the ene rgy balance has been restored.
You w ill also notice that engine id le speed has
been increased slightly . Thi s is normal and not
a cause for concern. By inc reasing engi ne id le
speed the additional e nergy requi red is gene r­
ated and the b attery is charged.
•
•

Checking and filling Engine hood
Releasing the engine hood
The engine hood is released from inside the
vehicle .
Fig. 172 Dr iver footwell: release lever
AUD I
Fig. 173 Rocker switch under the hood
Make sure the wiper arms are not raised up
from the w indshield. Otherw ise the paint
could be damaged.
.. Pull the lever under the instrument panel in
the d irect ion of the arrow
<=> fig. 172.
.. Raise the hood slightly<=> _&.
.. Press the rocke r switc h under the hood up­
ward
<=> fig. 173. This re leases the catch .
.. Open the hood .
A WARNING
Hot engine coo lant can burn you.
- To reduce the r isk of being burned, never
open the hood if you see or hear steam
or coolant escaping from the engine
compartment . Wait until no steam or
coolant can be seen or heard before care­
fully opening the hood.
Checkin g and fillin g 219
Working in the engine compartment
Be especially careful whenever you work in
the engine compartment.
Wh ene ve r y ou must perform an y wo rk in the
eng ine com pa rtm ent , for e xample checking
a nd filling diff ere nt fluids, th ere is a risk of
inju ry, burn s and accid ent s. To pr event per­
so nal injury alwa ys observe the foll owing
WARNING S. The engin e compartment of an y
v e hicle i s a h az a rdou s are a
<=> ,&.
_&. WARNING
To help avoid injury, be fore yo u check any ­
thing under the hood:
- Turn off the engine .
- Sw itch off the ignition.
- Apply the parki ng brake.
- Move selector leve r to "P" (Park).
- Always let the engine cool down. Hot
components w ill burn skin on contact .
- To reduce the risk of being burned, never
open the hood if you see or hear steam
or coo la nt escaping from the engine
compa rtment. Wait unt il no steam or
coolant can be seen o r heard before care­
fu lly opening the hood.
- Keep ch ildren away from the engine com­
pa rtment.
- Never sp ill fluids on hot engine compo­
nents . They can cause a fire .
- Never touch the rad iator fan. The auxili­
ary electric fan is temperat ure controlled
a nd can sw itch on suddenly .
- Never open the coolant reservoir cap
when the engine is still warm. The cool­
a nt system is p ressu rized and hot cool­
a nt cou ld spray o ut.
- Protect your face, hands and arm from
steam or hot engine coolant by plac ing a
thick rag ove r the cap when you open the
coo lant rese rvoir.
- If work on the fue l system o r the elec tri­
cal system is necessary:
- Always disconnect the battery.

220 Check ing and filling
- Never smoke or work near heaters or
open flames. Fluids in the engine com­
partment could start a fire.
- Keep an approved fire extinguisher im­
mediately available.
- To avoid electrical shock and persona l in­
jury while the engine is running or being
started, never touch:
- Ignition cables
- Other components of the high voltage
electronic ignition system.
- If you must perform a check or repa ir
with the engine running:
- First, fully apply the parking brake,
move selector lever to "P" (Park) .
- Always use extreme caution to prevent
clot hing, jewe lry, or long hair from get­
ting caught in the radiator fan, V-belts
or other moving parts, or from contact­ ing hot parts. Tie back hair before
start ing, and do not wear cloth ing that
will hang or d roop into the eng ine.
- Min imize exposure to emission and
chem ica l hazards c:> &. .
A WARNING
California Propos ition 65 Warning:
- Engine exhaust, some of its constituents,
and certa in veh icle compone nts co nta in
o r emit chemicals known to the State of
Californ ia to cause cancer and b irth de­
fects a nd rep roduct ive ha rm. In addition,
c ertain f luids con ta ine d in vehicles and
c ertain pro ducts of component wear co n­
tain or emi t chemicals known to the
State of California to cause cancer and
birth defects or other reproductive harm.
- Battery posts, terminals and re lated ac ­
cessories contain lead and lead com- pounds, chemica
ls known to the State of
California to cause cancer and reproduc­
tive harms. Wash hands after handling.
(D Note
When adding f luids, always make su re that
they are poured into the proper conta iner
or f iller opening, otherwise serious dam­
age to vehicle systems w ill occur.
® For the sake of the environment
To detect lea ks in time, inspect the vehicle
floor pan from underneath regularly. If
you see spots from oil or other veh icle flu­
i ds, have you r vehicle inspected by a n au­
thorized Audi dealer.
Closing the engine hood
.. Pull the hood down until the pressure from
the struts is reduced.
.. Let the hood
drop down an d latc h in place.
Do not try to push it shut; it may fail to en­
gage 9 /]}. .
A WARNING ,_ -
A hood that is not completely latched
could fly up and b lock your view while dr iv­
i ng.
- When you close the engine hood, check it to make sure the safety catch has proper­ly engaged. The hood shou ld be flush
wit h the surrou nding vehicle body pa rts .
- If you notice while driv ing that the hood
is not secured properly, stop at once and
close it.

230 Check ing and filling
• Read the brake fluid level from the brake
fluid reservoi r¢
fig. 180, ¢ page 221. The
brake f lu id leve l must be between the "MIN"
and "MAX" markings.
The location of the brake fluid reservoir can be
seen in the engine compartment illustration
co page 221.
The fl uid level may drop slightly after some
time due to the automatic adjustment of the brake pads . This is not cause for alarm .
I f the brake fluid level falls
considerably be­
l ow the "MIN" mark, the brake wa rning/indi ­
cator light- (U.S.
models) ;II (Canadian
models) will come on ¢
page 14. Do not con­
tinue to operate the vehicle. The comp lete
brake system should be thoroughly checked
by an authorized Audi dealer or other quali­
fied fac ility and the cause corrected. If the
brake fluid level is too low, the brake war ning/
in dicato r light w ill illuminate . Contact an au­
thor ized A udi dealer
immediately .
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid absorbs moistu re from the a ir . If
the water content in the brake fluid is too
h igh, corrosion in the brake system may result
after a per iod of t ime . The bo iling po int of the
b rake fluid w ill also decrease considerably and
dec rease braking per formance.
Therefore, the brake flu id must be changed
e ver y two yea rs. A lways use new b rake fluid
which confo rms to Fede ral Motor Vehicle
Standard "FMVSS 1 16 DO T 4".
The brake flu id rese rvoi r ca n be difficult to
r ea ch, therefo re , we re commend that yo u
have the brake fl uid changed by yo ur a utho r­
ized
Audi dealer. Your dea ler has the correct
too ls, the right brake fluid and the know-how
to do this for you .
A WARNING
-Brake flu id is poisonous. It must be stor­
ed only in the closed or iginal conta iner
out of the reach of children!
- Brake failure can resu lt from o ld or inap­
prop riate brake flu id . Obse rve these pre ­
cautions:
- Use only brake fluid that meets SA E
specification
J 1703 and conforms to
Federa l Moto r Ve hicle Standard 1 16 .
A lways check with your authorized A udi
dealer to make sure you are using the
correct brake fluid . The cor rect type of
brake flu id is also ind icated on the
brake flu id rese rvoir .
- The brake fluid must be new . Heavy use
of the brakes can cause a vapo r lock if
the b ra ke fluid is left i n the system too
l o ng. This can se riously affect the effi ­
c iency of the br akes as well as your
sa fety. This co uld resu lt in an accident.
(D Note
Brake fluid will damage the pai nt of you r
vehicle.
@ For the sake of the environment
Because of the p rob lem of proper disposal
of b ra ke fluid as well as the spec ial too ls
r equired and the nece ssary expe rti se, we
r ecommend that yo u have the brake fl uid
changed by yo ur authorized Aud i dea ler.
Battery
General information
U nder normal operat ing cond itions, the bat­
te ry in yo ur Audi does not need any ma inte­
nance . With
high outside temperatures or
l o ng da ily d rives we recommend that you have
the e lec trolyte leve l checked by a serv ice fa­
c ility. The electrolyte leve l should also be
checked each time the battery is cha rged
¢ page 233. .,..

Have the battery checked when you take your
vehicle in for service. Yo u are well advised to
replace a battery that is older than 5 years .
W ith certa in types o f airbag deployment, the
battery is disconnec ted from the vehicle elec ­
trica l system for safety reasons
c::> &. in Re­
pair, care and disposal of the airbags on
page 156.
Disconn ecting the battery terminal s
Some vehicle functions (power w indow regu­
l ators, for example) are lost if the battery ter­
minals are disconnected . These functions have
to be re learned after the battery terminals are
connec ted again. To prevent this, the battery
should only be disconnected from the vehicle
e lectrical system when absolutely necessary
for repairs .
Vehicles not driven for long period s
If you do not drive your vehicle over a period
of several days or weeks, electrical compo­
nents are gradually cu t back or switched off .
This reduces energy consumption and main ­
tains starting capability over a longer per iod
c::> page 192. Some of the convenience func­
tions may not operate, s uch as the inte rior
lights o r the power sea t adjustment . T he con­
ve nience fun ct ions wi ll be available again
when yo u switch on the ignition and start the
engine.
Winter operation
During the winter mont hs, ba ttery capaci ty
t ends to decrease as tempe rat ures d rop . Th is
is because more powe r is also consumed while
starting , and the headlights, rear window de ­
fogger, etc., are used more oft en.
Avoid unnecessary power cons umption, par­
ticularly in c ity t ra ff ic or when t raveling on ly
short distances. Let your a uthorized Audi
dealer check the capac ity of the vehicle bat ­
tery before winter sets inc::>
page 233. A well
charged battery w ill not only prevent starting
problems whe n the weather is cold, but will
also last longer .
Checkin g and fillin g 231
(D Tips
If your vehicle is left standing for seve ral
weeks at extremely low temperatures, the
vehicle battery shou ld be removed and
stored where it w ill not freeze. This will
prevent it from be ing damaged and having
to be replaced .
Working on the battery
Be especially careful when working on or near
the battery.
The battery is located in the l uggage compart­
ment under the floor. Before you check any­
th ing in the luggage compartment,
read and
h eed all WARNINGS
c::> &_ .
Always heed the safety warnings , when work­
ing on the vehicle battery or the vehicle e lec­
trical system to prevent injury.
The following WARNINGS are very
important when working on the battery:
Al ways heed the follo wing WARNING SYM­
BOLS and safety precautions when working on the battery.
@
®
Always wear eye protection.
Battery acid contains sulfuric acid.
Always w ear glove s and eye prot ec­
tion .
No
- sparks
-flames
- smoking .
When a battery i s charged, it produ­
ce s hydrogen gas wh ich i s ex plosive
and could cause per sonal injury .
Always keep the battery well out of ]
reach of children .
_& WARNING ~
Whenever working on the battery o r on
the electrical system, there is the risk of injury, accident and even fire . Read and
heed the following WARNINGS:
•
•

232 Checking and filling
-Always wear eye protection. Do not let
battery acid or any lead particles get on
your skin or clothing . Shield your eyes .
Explosive gases can cause blindness or
other injury .
- Battery acid contains sulfuric acid . Sulfu­
ric acid can cause blindness and severe
burns .
- Always wear gloves and eye protection.
Do not tilt the battery because acid
could leak out of the ventilation open­
ings.
- If you get battery acid in your eyes or
on your skin, immediately rinse with
cold water for several minutes and get
medical attention .
- If you should ingest any battery acid,
seek medical attention immediately.
- Do not expose the battery to an open
flame, electric sparks or an open light.
- Do not smoke.
- Do not interchange the positive and neg-
ative cables.
= When working on the battery , be sure
not to short-circuit the terminals with
tools or other metal objects. This would cause the battery to heat up very quickly,
which could lead to damage or explosion
and personal injury.
- When a battery is charged, it produces hydrogen gas which is explosive and
could cause personal injury .
- Always keep the battery well out of the
reach of children .
- Before work is done on the electrical sys­ tem, disconnect the negative ground ca­ble.
- Before performing any work on the elec­
trical system, switch
off the engine and
ignition as well as any electrical equip ­
ment . The negative cable on the battery
must be disconnected . If you are just go­
ing 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! Other­
wise you will set off the alarm. -
When disconnecting the battery, first
disconnect the negative cable and then
the positive cable.
- Before reconnecting the battery, make
sure all electrical consumers are switch­
ed off. Reconnect the positive cable first
and then the negative cable . Never inter ­
change 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 dis­
charged battery can freeze over at 32 °F
(0 °C) .
-Make sure the vent hose is always attach­
ed to the opening on the side of the bat­
tery .
- Never use batteries which are damaged.
There is the danger of an explosion! Al­
ways replace a damaged battery.
A WARNING
California Proposition 6S Warning:
- Battery posts, terminals and related ac­
cessories contain lead and lead com­
pounds, chemicals known to the State of
California to cause cancer and reproduc­
tive problems. Wash hands after han­
dling.
(D Note
- Do not disconnect the vehicle battery
when the ignition is on or when the en­ gine is running, otherwise, you will dam­
age electronic components in the electri­
cal system.
- If your vehicle is going to stand for a
long period of time without being driven,
protect the battery from "freezing", oth­
erwise it will be damaged and will then
have to be replaced .

Battery charging
Starting the engine requires a well charged battery .
Fig. 181 Eng ine co mpa rtmen t: connectors for a charg ­
er a nd jump sta rt cab les
A lwa ys re ad and heed all WARNING S below
c:> &. and c:> &. in Working on the battery on
page 231 .
.. Switch off the ignit ion and all electrical con­
sumers .
.. Make sure the area is well ventilated when
you charge the battery .
.. Open the engine hood
c:> page 219 .
.. Remove the cover (D by p ress ing on the ar­
row
c:> fig . 181.
.. Open the cove r@ on the positive term inal.
.. Connect the charger connectors according
to the instructions to the
jump start bolt s.
(Bolts under the red cover= "positive", Bolts
with hex head = "negative").
.. Only now plug the mains lead for the charg­
ing equipment into the wall outlet and turn
it on
c:> 8_ .
.. Ma ke sur e t he ch arging rat e is no t over
30 amp s/14 .8 Volt .
.. When the batte ry is f ully charged: Turn the
charging equ ipment off a nd remove the
mains lead from the wall outlet.
.. Now remove the clamps for the charging
equipment.
.. Close the red cover on the positive pole .
.. Close the hood
c:> page 220 .
A discharged battery can freeze at tempera­
tures of on ly 32
F0 (0 °C) . A llow a fro zen bat­
tery to thaw completely before attempt ing to
charge it
c:> .&. . However, we recommend not
using a thawed battery again because the bat -
Checking and fillin g 233
tery casing can be cracked due to ice forma ­
tion and can leak battery acid.
Battery charging (Maximum charging rate
of 30 amps /14.8 Volt )
When charging at low voltages (e.g. with a
trickle cha rger ), the battery cables do not
have to be disconnected f irst . The battery
caps should
not be opened when charging a
battery.
It is not necessary to remove the battery from
the luggage compartment, and it is a lso not
necessary to disconnect the cab les.
Fast ch arging the batte ry (charging rat e
a bove 14.8 V olt s)
For technica l reasons do not use a battery
charger that uses voltage greater than 14.8
Volts to charge your vehicle's battery .
A WARNING
-
Charging a battery can be dangerous .
- Always follow the operating instructions
provided by the battery charger manu­
facturer when charg ing your battery .
- Never charge a frozen battery. It may ex­
plode because of gas trapped in the ice .
Allow a frozen battery to thaw out first.
- Do not reuse batteries wh ic h were fro­
zen. The battery housing may have
cracked and weakened when the battery
froze.
- Cha rge the battery in a well ventilated
area . Keep away from open flame or elec­
trical spar k. Do not smo ke. Hyd rogen gas
generated by the battery is explos ive .
- To reduce the danger of explosion, never
connect or d isconnect charger cab les
while the charger is ope rat ing .
- Fast cha rging a batte ry is dange rous and
should only be at tempted by a compe­
tent techn ic ian wi th the prope r equip­
ment .
- Ba ttery acid that may spi ll dur ing charg­
ing should be washed off with a solution
of warm water and baking soda to neu ­
tralize the ac id.