2016 AUDI A6 check engine

-The oil filler cap must be properly secured
to prevent oil from be ing sprayed on the hot
engine and exhaust system when the engine
is running -fire hazard!
- If your skin has come in contact with the en­
gine oil, you must subsequently cleanse it
thoroughly .
@ Note
-Check the oil level using the MMI. If the
message
Pleas e reduce oil l evel appears,
contact your author ized Audi dealer or other
qualified workshop to have excess oil ex­
tracted if necessary.
- Audi do es not recommend th e use of o il
addit ive s. The y ma y damage the eng ine
and ad verse ly affect your New Vehicle
Wa rranty.
@ For the sake of the environment
- Under no circumstances can the o il come in
contact with the sewage network or the soil.
- Observe and follow legal regulations whe n
dispos ing of empty oil conta iners.
Changing the engine oil
We recommend that have your oil changed by an
authorized Audi dealer or a qualified service sta ­
tion.
Before you check anyth ing in the eng ine compart­
ment,
alw ays read and h eed all WARNING S c:> .&.
in Working in the engine compartment on
page 216.
The engine oil must be changed according to the
intervals specified in your Warranty
& Mainte­
nance booklet. This is very important because the
l ubricat ing propert ies of oil d iminish gradually
during normal vehicle use.
Under some circumstances the engine o il should
be changed more frequently . Change oil more of­
ten if you drive mostly short distances, operate
the veh icle in dusty areas or under predominant ly
stop-and -go traffic condit ions, or have yo ur vehi­
cle whe re temperatures remain below freezing
for extended periods.
Ch eck ing and Filling
Detergent additives in the oi l will make fresh oil
look dark after the engine has been running for a
short time . This is normal and is not a reason to
change the oi l more often than recommended.
Because of the problem o f proper disposal, along
with the specia l tools and necessary expertise re­
quired, we strongly recommend that yo u have
your o il changed by an authorized
Audi dealer or
a qual ified service stat ion.
If y ou choo se to chan ge your oil your self , please
note the following important information:
A WARNING "--
To reduce the risk of persona l injury if you
must change the eng ine oil in your vehicle
yourself:
- Wear eye protection.
-
-To reduce the r isk of burns from hot engine
oil, let the engine cool down to the touch.
- When remov ing the oil drain plug w ith your
f ingers, stay as far away as possible. Always
keep your forearm parallel to the ground to
he lp prevent hot oil from running down your
arm.
- Drain the oil into a container designed for
this purpose, one large enough to hold at least the tota l amou nt of oil in your engine.
- Engine oil is poisonous. Keep it well out of
the reach of children.
- Continuous contact with used engine o il is
harmful to your skin. Always protect your
skin by washing oil off thoroughly with soap
and water .
«I) Note
Never mix oil additives with your engine oil.
These additives can damage your engine and
adverse ly affect yo ur Audi limited New Vehi­
cle Warranty.
@ For the sake of the environment
- Before chang ing yo ur oi l, first make sure
you know where you can properly d ispose of
the used oil.
- Always dispose of used engine o il properly .
Do not dump it on ga rden soil, wooded
221

Checking and Filling
areas, into open streams or down sewage
drains.
- Recycle used engine oil by taking it to a used
engine oil collection facility in your area, or
contact a service station.
Cooling system
Coolant
T he 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 factory
with a permanent coolant which does not need to be changed . The coolant consists of a mixture of
specially conditioned water and the manufactur ­
er's glycol-based coolant additive G13 antifreeze
with anticorrosion additives (50% for USA mod­
els · 60% for Canadian models). This mixture
'
both assures the necessary frost protection and
protects metal components in the engine 's cool­
ing system from corrosion and scaling. It also
raises the boiling point of the coolant.
Do not reduce the concentration of the coolant in
the summer by adding plain water.
The propor­
tion of coolant additive must be at least 50% but not more than 60%
to maintain antifreeze
protection and cooling efficiency. If the coolant
frost protection is too low, the coolant could
freeze and damage the vehicle heating and en­
gine cooling system .
For year-round driving, antifree ze is added at the
factory for temperatures down to:
- -31 °F ( -3 5 °C) USA
- - 40 °F ( - 40 °C) Canada.
If you must add coolant, use a mixture of water
and coolant additive. Mixing the coolant additive
with distilled water is recommended.
_& WARNING
Before you check anything in the engine com­
partment, always read and heed all WARN-
222
INGS ~&. in Working in the engine compart­
ment on page 216.
(D Note
- Before winter sets in, have the coolant
checked to see if the coolant additive in your
vehicle is sufficient to meet the climate con­ ditions. This is especially important if you
live in a region where the winter is extreme­
ly cold . If necessary, increase the proportion
of coolant additive to 60%.
- When adding coolant additive to your cool­
ing system, remember:
- We recommend using only coolant addi­
tive G12++ or G13 (check the label) for
your vehicle. This coolant additive is avail­
able at authorized Audi dealers. Other
types of antifreeze can significantly re­
duce corrosion protection. The resulting
corrosion can cause a loss of coolant and
serious engine damage .
- Do not add any type of radiator leak sealant
to your vehicle's engine coolant. Adding ra ­
diator repair fluid may adversely affect the
function and performance of your cooling
system and could result in damage not cov­
ered by your New Vehicle Limited Warranty.
Checking the engine coolant level
The engine coolant level can be checked with a
quick glance.
Fig. 189 Eng in e compar tment: cover on the cool ant expan­
s ion tank
Before you check anything in the engine compart­
ment,
always read and heed all WARNINGS
~ A in Working in the engine compartment on
page 216. ..,.

• Park your vehicle on a level surface.
• Switch
off the ignition.
• Read the engine coolant level from the coolant
expansion tank¢
fig. 189, ¢ page 218,
fig. 186.
With a cold engine, the coolant level
should be between the "min" and "max" mark­
i ngs . When the engine is warm, the level may
be s light ly above the "max " marking.
The location of the coolant expans ion tank can be
seen in the engine compartment illustrat ion
¢pag e 218.
To obtain an accurate reading, the engine must
be sw itched
off.
The expansion tank in your vehicle is equipped
with an electric coolant level sensor.
When the coo lant level is too low, the warning
light in the Auto-Check System
c:> page 15 wi ll il­
luminate until you add coolant and the level has
been restored to normal. Even though there is an
e lectric coolant level sensor, we still recommend
you check the coolant level from t ime to t ime.
Coolant loss
Coolant loss may indicate a leak in the cooling
system. In the event of coolant loss, the cooling
system should be inspected immediately by your
authorized Audi dealer. It is not enough merely
to add coolant.
In a
sealed system, losses can occur only if the
boiling point of the coo lant is exceeded as a re­
sult of overheat ing.
A WARNING
The cooling system is under pressure and can
get very hot . Reduce the risk of scalding from
hot coolant by following these steps.
- Turn off the eng ine and allow it to cool
down.
- Protect your face, hands and arms from es­
caping fluid and steam by covering the cap
with a large, thick rag.
- Turn the cap slowly and very carefully in a
counter-clockwise direction while applying
light, downward pressure on the top of the
cap.
Checking and Filling
-To avoid being burned, do not spill anti­
freeze or coolant on the exhaust system or
hot engine parts. Under certain cond itions,
the ethylene glycol in engi ne coolant can
catch fire.
(D Note
Do not add any type of radiator leak sealant
to your vehicle's engine coolant. Add ing radia­
tor repair fluid may adversely affect the func­
tion and performance of your cooling system
and could result in damage not covered by
your New Vehicle Limited Warranty.
Adding coolant
Be very careful when adding engine coolant.
Before you check anything in the engine compart­
ment,
always read and heed all WARNINGS
¢.&. in Working in the engine compartment on
page 216.
• Requ irement: There must be a residual amount
of coolant in the expansion tank
c:> (D .
•Turnoff the engine .
• Let the engine cool down.
• Place a thick rag over the coolant expans ion
tank
c:>p age 222 , fig. 189 and carefully twist
the cap counter-clockwise
c:> _& .
• Add coo lant mixed in the correct ratio
c:> page 222, Coolant up to the MAX marking .
• Make sure that the fluid level remains stable.
Add more coolant if necessary.
• Twist the cap on again
tightly.
Replacement engine coolant must conform to ex ­
act specifications
c> page 222, Coolant.
We recommend using only coolant additive Gl2+
+ , Gl3
or in an emergency Gl2+. Do not use a
different additive. In an emergency use plain wa­
ter until you can get the correct additive and can
restore the correct ratio. This should be done as
soon as possible.
If you have lost a considerable amount of coo l­
ant, then you should add cold antifreeze and cold
water only when the engine is co ld.
Always use
new engine coolant when refi lling.
223

Check ing and F illing
Do not fill coolant above the "MAX" mark. Excess
coo lant wi ll be forced out through the pressure
relief valve in the cap when the eng ine becomes
hot.
A WARNING
- The cooling system is under pressure and
can get very hot . Reduce the risk of scald ing
from hot coolant by followi ng these steps.
- Tu rn off the engine and allow it to coo l
down.
- P rotect your face, h ands and arms from
escaping f lu id and steam by cover ing the
cap with a large, thick rag.
- Tu rn the cap slowly and very carefully in a
co unter -clockw ise direction while applying
light, downward p ressure on the top of
the cap.
- To avoid being bu rned, do not spill anti­
freeze or coolant on the exhaust system or
hot engine parts. Under certa in condi­
tions, the ethylene glycol in eng ine cool­
a nt can catch fire.
- Antifreeze is poisonous. A lways store anti­
freeze in its original container and well out
of the reach of children .
- If you dra in the coolant, it must be ca ught
and sa fely stored in a proper conta iner
clearly mar ked "poison".
(D Note
- Do not add coolant if the expansion tank is
empty . A ir cou ld enter the cooling system
a nd damage the eng ine. If this is the case ,
do no t continue dr iving. Seek professional
ass istance .
- Coolant pollutes t he e nvironment a nd could
cause an eng ine fire . Excess coolan t will be
fo rced o ut through th e pressure relief valve
i n the c ap whe n the eng ine be comes hot.
- If, in an emergency, o nly wate r can be add­
ed, the co rrect ratio between wate r and an­
ti fr ee ze ~
page 222 mu st be resto red a s
soon as possib le.
224
-
® For the sake of the environment
D raine d coolant should not be re use d. Always
d ispose of used coolant while observing a ll
environmental regulations.
Radiator fan
The radiator fan switches on automatically by it­
self
An a uxiliary e lectric ra diator fan switches on and
off depending on coo lant temperature and other
vehicle ope rating conditions .
A ft er yo u sw itc h t he engi ne off, the a uxi liary fan
can con tinue running for up to 10 m inutes -even
with t he ignitio n off .
It can even switch on again
l ater by itself~& . if
- t he tempera ture o f the engine coolan t rises d ue
to the heat build -up from the engine in the en­
gine compa rtment, or
- t he engine compar tment heats up beca use the
vehicle is pa rked in intense s unlight.
A WARNING
- To red uce the r is k of personal injury never
to uch the radiator fan .
- The a uxiliary e lectric fan is temperat ure
controlled and can switch on s uddenly even
when the engine is not running.
-
- The a uxiliary radiator fan switches on auto­
mat ically when the eng ine coolant reaches a
certain temperature and will continue to run
until the coo lant temperature d rops.

.... N
0 CJ ' M I.Cl ......
Brake fluid
Checking brake fluid level
Fig. 190 Engine compartment : cover on t he brake fluid
reservoir
N
N
-N ,::
~
Before you check anything in the engine compart­
ment,
always read and heed all WARNINGS
¢ A in Working in the engine compartment on
page 216.
.,. Read the brake fluid level from the brake fluid
reservoir
¢fig. 190, ¢page 218, fig. 186. The
brake fluid level must be between the "MIN "
and "MAX" markings.
The location of the brake fluid reservoir can be
seen in the engine compartment illustration
¢page 218.
The fluid level may drop slightly after some time
due to the automatic adjustment of the brake
pads. This is not cause for alarm.
If the brake fluid level falls
considerably below
the "MIN" mark, the brake warning/indicator
light
1111 (U.S. models) ;II (Canadian models)
will come on¢
page 14. Do not continue to oper­
ate the vehicle. The complete brake system
should be thoroughly checked by an authorized
Audi dealer or other qualified facility and the
cause corrected. If the brake fluid level is too
low, the brake warning/indicator light will illumi ­
nate. Contact an authorized Audi dealer
immedi­
ately.
Checking and Filling
Changing brake fluid
Have the brake fluid changed by an experienced
technician .
Brake fluid absorbs moisture from the air. If the
water content in the brake fluid is too high, cor­
rosion in the brake system may result after ape ­
riod of time . The boiling point of the brake fluid
will also decrease considerably and decrease
braking performance.
Therefore, the brake fluid must be changed
every
two years . Always use new brake fluid which con­
forms to Federal Motor Vehicle Standard "FMVSS
116 DOT 4" .
The brake fluid reservoir can be difficult to reach,
therefore, we recommend that you have the
brake fluid changed by your authorized
Audi
dealer. Your dealer has the correct tools, the
right brake fluid and the know-how to do this for
you.
A 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 inappro­
priate brake fluid . Observe these precau­
tions:
- Use only brake fluid that meets SAE speci­
fication
J 1703 and conforms to Federal
Motor Vehicle Standard 116. Always check
with your authorized Audi dealer to make
sure you are using the correct brake fluid.
The correct type of brake fluid is also indi­
cated 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.
This can seriously affect the efficiency of
the brakes as well as your safety. This
could result in an accident.
(D Note
Brake fluid will damage the paint of your vehi-
cle.
IJ>
225

Check ing and F illing
@ For the sake of the environment
Because of the prob lem of proper disposal of
brake fluid as we ll as the special tools re­
quired and the necessary expertise, we rec ­
ommend that you have the b rake fluid
changed by your author ized Audi dealer .
Battery
General information
Under normal operating conditions, the battery
in your Audi does not need any maintenance.
W ith
high outside temperat ures or long da ily
drives we recommend that you have the electro­
lyte level checked by a service fac ility . The elec­
trolyte level should also be chec ked eac h time
the battery is charged ¢
page 228 .
Have the battery checked when you take your ve­
h icle in for service. You a re well advised to re­
p lace a battery t hat is o lder than S years .
W ith certain types of a irbag dep loyment, the
battery is disconnected from the vehicle electr i­
cal system for safety reasons
¢ &. in Repair, care
and disposal of the airbags on page 157 .
Disconnecting the battery terminal s
Some vehicle functions (power window reg ula­
tors, for example) are lost i f th e battery termi ­
na ls are disconnected. These functions have to be
relearned after the battery termina ls are con­
nected aga in. To prevent th is , the batte ry shou ld
only be disconnected from the vehicle e lectr ica l
sys te m when abso lutely ne cessary for repairs.
Vehicles not driven for long periods
If you do not drive your vehicle over a period of
seve ral days or weeks, electrical components a re
gradua lly cut back or sw itched off . T hi s reduces
e n ergy cons umption and ma inta ins starti ng ca­
pab il ity over a longer pe riod
¢ page 192. Some
of the conve nience f unct io ns may not o pera te,
such as the inter io r lig hts or powe r seat a dju st­
ment . The convenience funct ions wi ll be avai lab le
again when you switch on the ignition and start
the engine.
226
Winter operation
Dur ing the winte r mon ths, ba ttery c apacity tends
to decrease as tempe ra tu res drop . This is be ­
ca use mo re power is also consume d while start ­
i ng, and the headlights, rear window defogger,
etc., are used more often.
Avo id unne cessary powe r consum ption, pa rticu­
l arly in city traffic or when traveling on ly short
distances . Let your author ized Audi dealer check
t h e capacity of the vehicle battery before winter
sets in~
page 228. A we ll charged battery will
not only p reve nt sta rting prob lems when the
weather is cold, but will also last longer.
(D Tips
If yo ur vehicle is left standing for several
weeks at extreme ly low temperatu res, the ve­
hicl e battery should be re m oved a nd stor ed
where it will not freeze. This w ill preven t it
fro m bei ng damaged and hav ing to be re­
p lac ed .
Working on the battery
Be e specially car eful when working on or near
t he bat tery.
The battery is loca ted in the luggage com part­
ment under the floo r. Befo re yo u check anything
i n the luggage compa rtment,
read and heed all
WARNINGS ¢
.cl·
Always heed the safety warnings , when working
o n the vehicle ba tte ry o r the veh icle elect rical
system to p reve nt injury.
The following WARNINGS are very important
when working on the battery:
Always heed the following WARNING SYM·
BOLS and safety precautions when working on
the battery.
®
Always wear eye protection.
A
Battery acid contains sulfuric acid . Al-
ways wear gloves and eye protection.

@
No
• sp ark s
• fl ame s
· sm oki ng .
&
Wh en a battery is charg ed , it produces
h yd rogen ga s which i s ex plosi ve and
c o uld c au se p ers onal injury .
®
Always keep the b atter y well out of
rea ch of child ren.
A WARNING
Whenever working on the battery or on the
electrical system, there is the risk of injury,
accident and even fire. Read and heed the fol­
lowing WARN INGS:
- Always wear eye protection. Do not let bat­
tery a cid or any lead pa rticles get on your
sk in or cloth ing. Sh ield your eyes. Exp losive
gases can cause blindness or other injury .
- Battery acid contains su lf ur ic ac id. Sulfur ic
acid can cause blindness and severe b urns.
-Always wear gloves and eye protection. Do
not tilt the battery because acid could leak
out of the ventilat ion open ings.
- If you get battery ac id in your eyes or on
your skin, immediately rinse with co ld wa­
ter for seve ral minutes and get medical at·
tention .
- 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 nega -
tive cab les.
- When working on the battery, be sure not to
short-c ircuit the terminals with tools or oth­
er meta l objects. Th is wou ld cause the bat­
tery to heat up very quickly, which could
lead to damage or explosion and persona l
injury.
- When a battery is charged, it produces hy­
drogen gas which is explosive and could
cause pe rsonal injury.
- Always keep the battery well out of the
reac h of ch ildren .
-
Check ing and Filling
-Before work is done on the electrical sys­
tem, disconnect the negat ive ground cable.
- Before performing any work on the electri­
cal system, switch off the engine and igni­
tion as well as any electrical equ ipment. The
negat ive cable on the battery must be dis­
connected . If you are just going to replace a
light bulb, then it is enough to switch off
the lights.
- Before d isconnecting the battery, switch off
the anti-theft a larm system! Otherwise you
will set off the alarm.
- When disconnecting the battery, first dis­
connect the negat ive cable and then the
positive cable.
- Before reconnect ing the battery, make sure
all electrical consumers a re switched off.
Reconnect the positive cable first and then
the negative cable. Never in terchange the
cables -this could start a fire !
- Never cha rge a froze n or a thawed-out bat ­
t ery . It co uld explode! If a battery has fro­
zen, then it must be replaced. A discharged
battery 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 exp losion! Always
replace a damaged battery .
A WARNING ,_____
California Proposition 65 Warning:
- Ba ttery posts, term inals and related acces ­
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive prob lems.
Was h hands after handling.
(D Note
- Do not disconnect the vehicle battery when
the ignition is on or when the engine is run­ ning, otherwise, you w ill damage electronic
components in the electrical system.
- If your ve hicle is go ing to stand for a long
period of time w ithout being driven, protect
the battery from "freezing", otherwise it .,..
227

Checking and Filling
will be d amage d and will then have to be re ­
placed.
Battery charging
Starting the engine requires a w ell charged bat­
tery.
F ig. 191 Eng ine co mpartmen t: connecto rs for a cha rge r
and jump start cab les
Alwa ys re ad and h eed all WARNINGS below
¢ A and ¢ A in Working on the battery on
page 227.
• Switc h off the ignition and all elec trical con­
sumers .
• Make sure the area is well venti lated when you
charge the battery .
• Open the engine hood
c> page 216.
• Open the red cover on the positive pole
¢ fig. 191.
• Connect the charger connectors according to
the instructions to the
j um p sta rt bo lt s . (Bolts
u nder the red cover= "positive" , Bolts w ith hex
head = "negative ") .
• Only now pl ug the mains lead for the charging
equipment into the wall outlet and tur n it on
¢£ .
• Make sure the charg ing rate is not o ver
30 a mps/14 .8 Volt .
• When the battery is fully charged: Turn the
charging equipment off and remove the mains
lead from the wall outlet .
• Now remove the clamps for the charging equ ip-
ment .
• Close the red cover on the positive pole.
• Close the hood
c> page 217 .
A discharged battery can free ze at temperatures
of only 32 F
0 (0 °C). A llow a frozen battery to
228
thaw completely before attempting to charge it
c> & . However, we recommend not using a
thawed battery aga in because the battery cas ing
can be cracked due to ice formation and can leak
battery ac id.
Batte ry cha rging (M ax imum charg ing rate of
30 amps /14 .8 V olt)
When charging at low voltages (e.g. with a tric k­
le ch arger ),
the battery cables do not have to be
disconnected first . 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 nec­
essary to disconnect the cables.
Fa st cha rging the batt ery (charg ing rat e
above 14 .8 Volt s)
For techn ical reasons do not use a battery charg­
er that uses voltage greater than 14.8 Volts to
charge your veh icle's battery.
&_ WARNING
Charg ing a battery can be dangerous .
- Always follow the operating instructions
provided by the battery cha rger manufactur­
er when charging your ba tte ry .
- Never charge a frozen battery . It may ex­
plode because of gas trapped in the ice. Al­
low a froze n battery to thaw out first.
- Do not reuse batter ies which were frozen.
The battery hous ing may have c racked and
weakened when the battery fro ze.
- Cha rge the batte ry in a well ventilated area .
Keep away from open flame or elect rical
sp ark. Do not smoke. Hydrogen gas generat­
ed by the batte ry is e xplosive.
- To red uce the da nger of explosion, never
connect or d isconnect c harger c ables while
the charger is ope ra ting.
- Fa st c harg ing a bat tery is dange rous and
should o nly be atte mpted by a compe ten t
technician w ith the proper equipment .
- Ba tte ry a cid that may spill d uring charging
should be washed off w it h a so lution of
warm water and baking soda to neutralize
the acid.