2012 AUDI A6 check engine light

222 Checking and filling
Engine compartment
Engine compartment overview
These are the most important items that you can check.
Fig. 171 Typ ical layout for contai ners and eng ine o il filler cap
(D Jump start point(-) with hex
head screw .... ............. 233, 268
@ Jump start point(+) under a cov-
er .. .. ............... .... . 233,268
@ Brake fluid reservoir ((0)) .. .. .
© Engine oil filler cap ( ® Coolant expansion tank (-L) .. .
® Windshield/headlight washer
t . (.'R) con ainer ,,.., ............ . .
229
225
227
234
The engine oil filler neck (item @) may be lo­
cated in a different area depending on the ver­
sion of the engine.
~ WARNING
Before you check anything in the engine
compartment, always read and heed all
WARNINGS
¢ &. in Working in the engine
compartment on page 220.
-
Engine oil
Engine oil specifications
The engine oil used in your Audi needs the
right kind of oil.
The engine in your Audi is a sophisticated
powerplant that was built to exacting specifi­
cations . This engine needs the right kind of
engine oil that meets specifications regarding
quality and viscosity so that it can run
smoothly and reliably . Choosing the right oil
and changing oil within the t ime and mileage
intervals printed in you r vehicle's Warranty
&
Maintenance booklet matters a lot more to­
day than it did years ago . Audi has developed
a special quality standard for engine oil that
will help assure that your vehicle's engine will
get the lubrication it needs for proper opera-
tion. ..,.

224 Check ing and filling
temperatures stay below freezing point for
long periods.
Detergent add it ives in the o il w il l make fresh
oil look dark after the eng ine has been run­
ning for a short time . This is norma l and is not
a reason to change the oi l more often than
recommended.
D am age or m alfunc tions du e to lack of
m ainten ance
It is essential that you change your oil at the recommended in tervals using only engine o il
that complies with Audi oi l standard
VW 502 00. You r Limited New Vehicle War­
ranty does not cover damage or malfunctions
due to fail ure to fo llow recommended mainte­
nance and use requ irements as set forth in
the Audi Owner's Manual and Warranty &
Maintenance book let . Your dealer will have to
deny warranty coverage unless you present to
the dea ler proof in the form of Service or Re­
pa ir Orders that all scheduled ma intenance
was performed in a t imely manner.
Eng ine oil consumption
The engine in your vehicle depends on an ade­
quate amount of oil to lubricate and cool all
of its moving parts.
In order to provide effective lubrication and
cool ing of internal engine components, a ll in­
ternal comb ustion eng ines consume a certa in
amount of oil. O il consumption varies from
engine to engine and may change significantly
over the life of the engine. Typica lly, engines
with a specif ied break-in period (see
¢
page 196) consume more oil during the
break-in period than they consume after oil
consumption has stabilized.
Under norma l conditions, the rate of oil con­
sumpt ion depends on the quality and viscosity
of the oil, the RPM (revolutions per m inute) at
which the engine is operated, the ambient
temperature and road condit ions . Further fac­
tors are the amount of oil d ilution from water
condensat ion or fuel residue and the ox ida­
tion level of the oi l. As any engine is subject to wear as mi
leage builds up, the oil consump­
tion may increase over time until replacement of worn components may become necessary.
With a ll these variab les coming into play, no
standard rate of oil consumption can be es­
tablished or specified. There is no alternative
to regu lar and frequent check ing of the o il lev ­
el, see Note.
If the yellow engine oil leve l warning symbo l
in the instrument cluster
II! lights up, you
shou ld check the oil leve l as soon as possib le
¢
page 225. Top off the oil at your earliest
convenience
¢ page 225.
A WARNING '"---
Before you check anythi ng in the engine
compartment, always read and heed all
WARNINGS¢
A in Working in the engine
compartment on page 220.
(D Note
Driving w ith an insufficient o il level is like­
ly to cause severe damage to the engine .
(D Tips
-The oil pressu re warn ing display. is
not an indic ator of the oil le vel. Do not
r el y on it . In ste ad, ch eck the oil lev el in
y our engin e at r eg ular inter vals , pref ­
erably ea ch time you r efu el, and alwa ys
before going on a long trip .
- If you have t he impression yo ur engine
cons umes ex cessive amoun ts of o il, we
recommend that you consu lt your Aud i
dea ler to have the cause of your concern
properly diagnosed. Keep in mind that
the accurate meas urement of oi l con­
sumption requ ires great care and may
take some t ime. Your Audi dea ler has in­
structions about how to measure oil con­
sumption accurately.
-

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 .

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 .

268 Emergency situations
Emergency situations
General
This chapter is intended for trained emer­
gency crews and working personnel who
have the necessary tools and equipment to
perform these ope rations.
Starting by pushing or
towing
Q;) Note
Vehicles w ith an automatic transmission
cannot be started by pus hing o r tow ing.
Starting with jumper
cables
If necessary, the engine can be started by
connecting it to the battery of another vehi­
cle.
If the engine should fail to start because of a
discharged or weak battery, the battery can be
connected to the battery of
another vehicle,
using a
pair of jumpe r cables to start the en­
g ine .
Jumper cables
Use only jumper cables of sufficiently large
cross section to carry the starter current safe­
ly. Refer to the manufacturer's specif ications.
Use only jumper cables with
insulated termi­
na l clamps which are distinctly marked:
plus(+) cable in most cases colored red
minu s(-) cable
in most cases colored black .
A WARNING
Batteries contain electricity, acid, and gas.
Any of these can cause very serious or fatal
inju ry. Follow the instructions below for
safe handling of your veh icle's battery.
- Always shield you r eyes and avoid lean­
ing over the battery whenever possible.
- A discharged battery can freeze at tem­
peratures just be low 32 °F (0 °C). Before connecting a
jumper cable, you must
thaw the frozen battery complete ly, oth­
erwise it could explode.
- Do not allow battery acid to contact eyes
or skin. Flush any contacted area with
water immediately.
- Improper use of a booster battery to start a vehicle may cause an explosion.
- Vehicle batteries generate explosive gas­
es. Keep sparks, flame and lighted ciga­
rettes away from batteries.
- Do not try to jump start any vehicle with a low acid level in the battery.
- The vo ltage of the booster battery must
also have a 12-Volt rating. The capacity
(Ah) of the booster battery should not be
lower than that of the discharged bat­
tery . Use of batteries of d ifferent voltage
or substantially different "Ah" rating
may cause an exp losion and personal in­
jury.
- Never charge a frozen batte ry. Gas trap­
ped in the ice may cause an explosion.
- Never charge or use a battery that has
been frozen. The battery case may have
be weakened.
- Use of batter ies of different voltage or
substantially different capacity (Ah) rat­
ing may cause an exp losion and injury.
The capacity (Ah) of the booster battery
should not be lower than that of the dis ­
charged battery.
- Before you check anything in the engine
compartment, always read and heed a ll
WARNINGS¢
page 214, Engine com­
partment.
«I) Note
-Applying a higher voltage booster bat­
tery will cause expensive damage to sen­
sitive electronic components, such as
contro l units, relays, rad io, etc.
- There must be no electrical contact be­
tween the vehicles as otherwise current
could already start to flow as soon as the
positive(+) terminals are connected. ..,_