2012 AUDI A6 check engine

226 Check ing and filling
and ad versely a ffect yo ur New Vehicl e
W arr ant y.
@) For the sake of the environment
- Under no circumstances can the oil come
in contact with the sewage network o r
the soil.
- Observe and follow lega l regu lations
when disposing of empty oil containers .
Changing the engine oil
We recommend that have your oil changed by
an authorized Audi dealer or a qualified serv­
ice station.
Before you check anything in the engine com­
partment,
a lw ays rea d an d h eed all WARN­
INGS c::> .& in Working in the engine compart­
ment on page 220.
The engine oil must be changed accord ing to
the intervals specified in your Warranty
&
Maintenance book let. This is very important
because the lubricating properties of oil di­
minish gradua lly during normal vehicle use .
Under some ci rcumstances the engine oi l
should be changed more frequently. Change
oil more often if you drive most ly short dis­
tances, operate the vehicle in dusty areas or under predominantly stop-and-go traffic con­
ditions, or have your vehicle where tempera­
tures remain below freezing for extended pe ­
riods .
Detergent addit ives in the oil w ill make fresh
oil look dark after the engine has been run­ n ing for a short time. This is normal and is not
a reason to change the oil more often than recommended.
Because of the problem of proper disposal,
along w ith the special tools and necessary ex ­
pertise required , we strongly recommend that
you have your o il changed by an authorized
Audi de ale r or a qual ified servi ce station.
If y ou choo se to c hang e y our oi l y our self,
please note the followi ng important informa­
tion :
A WARNING
To reduce the risk of personal injury if you
must change the eng ine oil in your vehicle
yourself:
- Wear eye protect ion.
- To reduce the risk of burns from hot en- gine oil, let the engine cool down to the
touch.
- When removing the o il dra in plug with
your fingers, stay as far away as possible.
Always keep your forearm parallel to the
ground to help prevent hot oil from run­n ing down you r arm.
- Dra in the oil into a container designed
for this purpose, one large enough to
hold at least the total amount of oil in
your engine.
- Engine oil is poisonous. Keep it we ll out
of the rea ch of childre n.
- Continuous contact with used eng ine o il
is harmfu l to your sk in. Always protect
your skin by washing oil off tho roughly
with soap and wate r.
@ Note
Never mix oil additives with your engine
oi l. These additives can damage your en­
g ine and adversely affect you r A ud i Limit­
ed New Veh icle War ranty.
@ For the sake of the environment
- Before changing your oil, first make su re
you know where you can prope rly dispose
o f the used oil.
- Always dispose of used eng ine oi l proper­
ly. Do not dump it on garden soil, wood­
ed areas, into open streams or down
sewage drains.
- Recycle used engi ne oil by taking it to a
used engine oil collection facility in you r
area, or contact a service station.

Engine cooling system
Coolant
The engine coolant performs two functions: it
keeps the engine from overheating and it pro ­
tects the engine from freezing in the winter .
The cooling system is sealed and generally re­
quires little attention .
The cooling system has been filled at the fac­
tory with a permanent coolant which does not
need to be changed. The coolant consists of a
mixture of water and the manufacturer's gly ­
col-based coolant additive G12++ antifreeze
with anticorrosion additives (50% for USA
models; 60% for Canadian models). This mix­
ture both assures the necessary frost protec­
tion and protects metal components in the
engine's cooling system from corrosion and
scaling. It also raises the boiling point of the
coolant.
Do not reduce the concentration of the cool­
ant in the summer by adding plain water.
The
proportion of coolant additive must be at
least 50% but not more than 60%
to main­
tain antifree ze protection and cooling efficien­
cy. If the coolant frost protection is too low,
the coolant could freeze and damage the vehi ­
cle heating and engine cooling system.
For year-round driving, antifreeze is added at
the factory for temperatures down to:
- -31 °F ( -3 5 °C) USA
- -40 °F ( - 40 °C) Canada.
You can mix the G12 ++ coolant additive with
other additives (G12+ or G12). Always check
with your authorized Audi dealer.
& WARNING
Before you check anything in the engine
compartment, always read and heed all
WARNINGS
~ .&. in Working in the engine
compartment on page 220.
(D Note
- Before winter sets in, have the coolant
checked to see if the coolant additive in
Checking and filling 22 7
your vehicle is sufficient to meet the cli­
mate conditions. This is especially impor­
tant if you live in a region where the win­
ter is extremely cold. If necessary, in­
crease the proportion of coolant additive
to 60% .
- When adding coolant additive to your
cooling system, remember :
- We recommend using only coolant ad­
ditive G12++ (check the label) for your
vehicle. This coolant additive is availa­
ble at authorized Audi dealers. Other
types of antifreeze can significantly re­
duce corrosion protection. The result­
ing corrosion can cause a loss of cool­
ant and serious engine damage.
- Do not add any type of radiator leak seal­
ant to your vehicle's engine coolant.
Adding radiator repair fluid may adverse­
ly affect the function and performance of
your cooling system and could result in
damage not covered by your New Vehicle
Limited Warranty.
Checking the engine coolant level
The engine coolant level can be checked with
a quick glance.
M AX f
MINf
Fig.174 Engine compar tment: markings on the coo l­
an t expa nsion tank
Before you check anything in the engine com­
partment,
always read and heed all WARN­
INGS ¢.&, in Working in the engine compart­
ment on page 220 .
"' Park your vehicle on a level surface .
"' Switch off the ignition.
"' Read the engine coolant level from the
coolant expansion tank~
fig. 174. With a

228 Check ing and filling
cold engine, the coo lant level should be be ­
tween the "min" and "max" markings. When
the engine is warm, the level may be s light ly
above the "max" marking.
The location of the coolant expansion tank
can be seen in the engine compartment illus­
tration
r:::;, page 222.
To obtain an accurate reading, the engine
must be switched
off.
The expansion tank in you r vehicle is equipped
with an e lectric coolant level sensor.
When the coolant level is too low, the warning light in the Auto-Check System
r:::;, page 16 will
i l lum ina te unti l you add coolant and the level
has been restored to normal. Even though
there is an electric coolant level senso r, we
still recommend you check the coolant leve l
from time to time.
Coolant los s
Coolant loss may indicate a leak in the cool ing
system. In the event of coolant loss, the cool ­
ing system should be inspected immediately
by your authorized Audi dealer. It is not
enough merely to add coolant.
I n a
sea led system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheat ing.
A WARNING
The cooling system is under pressure and
can get very hot. Reduce the risk of scald­
ing from hot coolant by following these
steps.
- Turn
off the engine and allow it to cool
down.
- Protect yo ur face, hands and arms from
escaping fluid and steam by covering the
cap with a large, thick rag.
- Turn the cap slowly and very carefully in
a counter-clockwise direction wh ile ap­
plying light, downward pressure on the
top of the cap.
- To avoid be ing burned, do not spill ant i­
freeze or coolant on the exhaust system
'
or hot engine parts. Under certain cond i­
tions, the ethylene glycol in engine coo l­
ant can catch fire.
(D Note
Do not add any type of radiator leak sea l­
ant to your vehicle's engine coolant. Add­ i ng radiator repa ir fl uid may adverse ly af­
fect the funct ion and performance of your
cooling system and could result in damage
not covered by your New Veh icle L imited
War ranty.
Adding coolant
Be very careful when adding engine coolant.
Before you check anyth ing in the eng ine com­
partment,
always read and heed all W ARN­
INGS c:> A in Working in the engine compart­
ment on page
220 .
.. Turn off the engine.
.. Let the engine cool down.
.. Place a thick rag over the coolant expansion
tank
<:;> page 227, fig . 174 and carefully
twist the cap co unte r-clockwise c:> .&, .
.,. Add coolant .
.,. Twist the cap on aga in
tightly.
Replacement engine coo lant must conform to
exact spec ificat ions
r:::;, page 22 7, Coolant.
E ven in an emerge ncy, if coolant add i-
t ive G12 ++, G 12+ or G12 is not available, do
not use a d iffe rent additive. Use plain water
instead unti l you can get the correct additive
and can restore the correct ratio . This shou ld
be done as soon as possible.
If you have lost a considerab le amount o f
coolant, then you sho uld add cold antifreeze
and co ld water on ly w hen the engine is cold.
Always use
new engine coo la nt when refilling.
Do not fill coola nt above the "MAX" mark . Ex­
cess coola nt will be fo rced out through the
pressure relief valve in the cap w hen the e n-
gine becomes hot. .,.

_& WARNING
-The cooling system is under pressure and
can get very hot. Reduce the risk of
scald ing from hot coolant by following
these steps.
- Turn
off the engine and a llow itto cool
down.
- Protect your face, hands and arms from
escaping fluid and steam by covering
the cap with a large, thick rag.
- Turn the cap slow ly and very carefully
in a counter-clockwise direction while
applying light, downward pressure on
the top of the cap.
- To avoid being burned, do not spi ll an­
tifreeze or coolant on the exhaust sys­
tem or hot engine parts . Under certain
conditions, the ethylene glycol in en­
g ine coolant can catch fire .
- Antifreeze is poisonous. Always store an­
tifreeze in its or iginal containe r and we ll
out of the reach of children.
- If you drain the coolant, it must be
caught and safely stored in a proper con­
tainer clearly marked "poison".
(D Note
- Coolant pollutes the env ironment and
could cause an engine fire. Excess cool­
ant will be forced out through the pres­
su re relief valve in the cap when the en­
gine becomes hot.
- If, in an emergency, only water can be
added, the cor rect ratio between water
and antifreeze ¢
page 227 must be re­
stored as soon as possib le.
@ For the sake of the environment
Drained coolant should not be reused . A l­
ways dispose of used coolant while obse rv­
ing all environmental reg ulations.
Checkin g and fillin g 229
Radiator fan
The radiator fan switches on automatically by
itself.
An auxiliary electric radiator fan switches on
and
off depending on coolant temperature
and other vehicle operat ing cond it ions .
After you switch the engine
off, the auxiliary
fan can continue running for up to 10 minutes
- even with the ignition
off. It can even switch
on again later by itself ¢&. , if
- the temperature of the engine coo lant rises
due to the heat build-up from the engine in
the engine compartment, or
- the engine compartment heats up because
the vehicle is parked in intense sunlight.
_& WARNING
-To reduce the risk of personal injury nev­
er touch the radiator fan .
- The auxiliary electric fan is temperature
controlled and can sw itch on suddenly
even when the engine is not running.
- The a uxiliary radiator fan sw itches on au­
tomatically when the engine coo lant
reaches a certa in temperature and will
continue to ru n until the coolant temper­
ature drops.
Brake fluid
Checking brake fluid level
Fig. 175 En gin e compartment: mark ings on th e brake
fluid rese rvoir

230 Check ing and filling
Before you check anything in the engine com­
partment,
always r ea d and heed all W ARN­
INGS
¢ A in Working in the engine compart­
ment on page 220.
• Read the brake fluid leve l from the brake
fluid reservoir
¢ fig. 175. The brake fluid
l evel 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 222.
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 b rake 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 shou ld be thoroughly checked
by an authorized Audi dealer or other quali­
fied fac il ity and the cause corrected. If the
brake fluid level is too low, the brake warn ing/
i ndicator light w ill illuminate. Contact an au­
thor ized Audi dealer
imm ediatel y.
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
ev ery tw o y ear s. Always 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 can be difficult to
r each, 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 tools, the
right brake flu id and t he know -how
to do this for you.
A WARNING
-- Brake flu id is poisonous. It must be stor-
ed only in the closed or igina l container
out of the reach of children!
- Brake failure can resu lt from o ld or inap­
propriate brake f lu id. Observe these pre­
cautions:
- Use only brake f luid that meets SA E
spe cifi cation
J 17 03 and conforms to
Federa l Motor Vehicle Standard 1 16 .
Always chec k with your authorized A udi
dealer to make sure yo u are using the
correct brake fluid. The cor rect type of
brake flu id is also ind icated on the
brake f lu id reservoir.
- The brake fluid must be new. Heavy use
of the brakes can cause a vapor lock if
the brake fluid is left i n the system too
long . This can se riously affect the effi­
c iency of the brakes as well as your
safety . T h is i:ou ld result in an ai;i;ident.
(D Note
Brake fluid will damage the pai nt of you r
vehicle .
@ For the sake of the environment
Because of the prob lem of proper disposal
of brake fluid as well as the spec ial too ls
r equired and the necessary expertise, we
r ecommend that yo u have the brake flu id
changed by yo ur autho rized Aud i dea le r.
Battery
General information
Under normal operat ing cond itions, the bat­
te ry in your Audi does not need any ma inte­
nance. With
high outside temperatures or
long da ily drives we recommend that you have
the e lectrolyte leve l che cked by a se rv ice fa­
c il ity. The electroly te leve l should also be
chec ked each time the battery is cha rged
¢ page 233 .

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. 176 Eng ine compartment : connectors for a charg ­
er and 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 220 .
.. Open the red cove r on the posit ive pole
c:>fig. 176.
.. Connect the charger connectors accord ing
to the instructions to the
jump start b olts .
(Bolts under the red cover= "positive", Bolts
with hex head= "negative").
.. Only now plug the mains lead for the charg­
ing equipmen t into the wall outlet and turn
it on
c:> 8_ .
.. Ma ke sur e t he charging rat e is not over
30 amp s/14 .8 Vol t.
.. When the batte ry is fully charged: Turn the
charging eq uipment off a nd remove the
ma ins 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 2 21.
A discharged battery can free ze at tempera­
tures of on ly 32 F
0 (0 °C). A llow a frozen bat­
tery to thaw completely before attempt ing to
charge it
c:> .&. . However, we recommend not
using a thawed battery again because the bat-
Checkin g 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 also not
necessary to disconnect the cables.
Fast ch arging the batte ry (charging rat e
a bove 14.8 Volt 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 dange rous .
- 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 bat tery is explos ive.
- To reduce the danger of explosion, never
connect or d isconnect charger cab les
while the charger i s ope rat ing.
- Fast cha rging a batte ry is dange rous and
should only be at tempted by a compe­
tent techn ician 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.

234 Checking and filling
(D Note
Never use a fast charger as a booster to
start the engine. This will seriously dam­
age sensitive electronic components, such
as control units, relays, radio, etc., as well
as the battery charger.
Battery replacement
The new battery must have the same specifi­
cations and dimensions as the original equip­
ment battery.
Intelligent energy management in your vehi­
cle is responsible for distributing the electri­
cal energy throughout your vehicle
~ page 194. The intell igent energy manage­
ment system will keep the engine battery
charged better than vehicles without this sys­
tem. To make sure the additional electrica l en­
ergy is available once again after you have
changed the battery, we recommend that you install batteries of the same type and manu­
facture only (the same as those installed at
the time your vehicle was delivered). Specifi­
cations are listed on the battery housing. Your
author ized dealer must code the battery in
the energy management system to enable you
to use the energy management funct ions cor­
rectly after replacing the battery .
The new battery must have the same capacity,
voltage (12 volts), amperage, construct ion
and plug sealing.
When installing the battery, make sure the ig­
nition and all electr ical consumers are switch ­
ed off.
(D Note
Make sure the ventilation hose on the side
of the battery is connected, otherwise
fumes or battery ac id can leak out.
@ For the sake of the environment
Because of the problem of proper disposal
of a battery, we recommend your author­
ized Audi dealer change the battery for
you . Batteries contain su lfuric acid and l
ead and must always be disposed of prop­
erly in compliance with all environmental
regulations. Disposing of vehicle batter ies
i mproperly is very dangerous to the envi­
ronment.
Windshield/head Light
washer container
Fig. 177 En g in e compart men t: w inds hield and head ­
lighr washer fluid reservoir
The washer fluid conta iner is marked w ith 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 220.
"' Lift the filler cap tongue to add washer flu ­
id. You can fill the container to the top.
"' Press the cap back onto the filler neck after
fi lling the container.
You can find the reservoir
capacity in the table
in
~ page 2 76.
Clean water should be used when filling up. If
possible, use soft water to prevent scaling on
washer jets. Always add a glass cleaner solu­
tion (with frost protection in the winter).
@ Note
Do not mix engine coolan t ant ifreeze or
any other additives to fill up the wind­
shield washer reservoir .