2015 AUDI S6 engine overheat

Always apply brakes early. When driving
downhill, shift into a lower gear to use the en­
g ine braking effect to slow the vehicle . Use of
the brakes a lone can cause them to overheat
and fail.
Air suspension*
When driving with a trai ler, activate the trailer
mode of the air suspension. Switch the air
suspension trailer mode on when you are tow­
ing a trailer. This will limit the regulation by
the air suspension while driving. Select in the
MMI:
! CARI function button> (C ar) * systems
control button > Vehicle settings > Air susp.:
towing > On .
Coolant temperature
The coolant temperature gauge¢ page 11
must be observed carefully. The coolant tem­
perature can increase if you drive on long in­
clines in a low gear at high engine speeds . Re­
duce your speed immed iately if the LEDs in
the top pa rt of the display turn on.
For more information about indicator lights,
refer to. ¢
page 16 .
A WARNING
Anyone no t properly restrained in a mov­
ing veh icle is at a much greater ris k in an
accident . Never let anyone ride in your car
who is not properly wearing the restraints
provided by Audi .
Trailer towing tips
Important to know
Your vehicle handles differently when tow ing
a trailer because of the addit ional weight and
d ifferent weight distribution . Safety, perform­
ance and economy w ill greatly depend on how
carefully you load your trailer and operate
your rig.
Before you actually tow your trailer, practice
M N turning, stopping and backing up in an area 0
~ away from traffic. Keep practicing until you
~ have become comp lete ly fam iliar with the way 1.1'1 ,...., 1.1'1 ,....,
Trailer towing 207
your vehicle-trai ler combination behaves and
responds.
Backing up is difficult and requires practice .
Backing up with a trailer generally req uires
steering action opposite to that when backing
up your vehicle without a trai ler.
Maintain a greater distance between your ve­
hicle and the one in front of you. You will need
more room to stop. To compensate for the
trailer , you wi ll need a larger than normal
turning rad ius.
When passing, remember that you cannot ac­
ce lerate as fast as you norma lly would be­
cause of the added load. Make sure you have
enough room to pass . After passing, allow
plenty of room for your trailer before chang­
ing lanes again .
Avoid jerky starts, sharp turns or rapid lane changes.
(D Tips
- Do not tow a trailer during the break-in
period of your vehicle.
- If you tow a trailer, your Audi may re­
quire more frequent maintenance due to
the extra load ¢
page 292.
Parking on a slope
Do not park on a slope with a trailer. If it can­
not be avoided, do so only after doing the fol­ lowing:
When parking:
.,. App ly the foot brake .
.,. Have someone p lace chocks under both the
vehicle and the trailer wheels.
.,. With chocks in place, slowly release the
brakes until the wheel chocks absorb the
load .
.,. Turn the wheels towards the curb.
.,. Apply the parking brake .
.,. Select the P selector lever posit ion.
When re starting after parking:
.,. App ly the foot brake.
.,. Start the engine.
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228 Check ing and filling
- Always dispose of used engine oil proper ­
l y . Do not dump it on garden soi l, wood­
ed areas, into open streams or down
sewage dra ins.
- Recycle used engine oil by taking it to a
used engine oil collection facility in your
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
qu ires 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 spec ially conditioned water and the
manufacturer's glycol-based coolant addi-
tive G13 antifreeze with ant icorros ion addi­
tives (50% for USA models; 60% for Canadian
models). This mixture both assures the neces­
sary frost protection and protects metal com­
ponents in the engine's coo ling system from
corrosion and scaling . It also raises the boil­
ing point of the coolant.
Do not reduce the concentration of the coo l­
ant in the summer by adding plain water.
The
p ropo rtion of coolant add itive must be at
l e a st 50 % but not mo re th an 60 %
to ma in­
tain antifreeze protection and cooling efficien­
cy . If the coolant frost protect ion is too low,
the coo lant cou ld freeze and damage the veh i­
cle heating and eng ine cool ing system.
For year-round driving, antifreeze is added at
the facto ry for temperatures down to:
- -31°F(-35°C)USA
- -40 °F ( -40 °C) Canada.
If you m ust add coo lant, use a m ix tu re of wa ­
ter and coo lant addit ive . M ixing the coolant
additive with disti lled water is recommended .
A WARNING
Before you check anything in the engine
compartment, always read and heed all
WARNINGS~ &.
in Working in the engine
compartment on page
222 .
(D Note
-Before winter sets in, have the coolant
checked to see if the coolant additive in
your vehicle is sufficient to meet the cli­ mate conditions. This is especia lly impor­
tant if you live in a reg ion where t he win ­
t er is ex treme ly cold. If necessary, in­
crease the p roportion of coo lant add it ive
to 60% .
- When adding coolant addi tive to yo ur
c ooling sys tem, remembe r:
- We recommend us ing on ly coolant ad­
d itive G12++ or G13 (check the label)
for your vehicle . This coolant additive is
ava ilable at autho rized Aud i dea le rs.
Other types of antifree ze ca n sign ifi­
ca ntly reduce co rros io n protec tion. The
res ulting corrosion c an cause a loss of
coolant and serious engine damage.
- Do not add any type of r ad iator le ak seal­
ant to yo ur vehicle 's engine coolant .
Adding radiator repair flu id may adverse­
ly affect the function and performance of
your cooling system and cou ld resu lt 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.
F ig. 1 91 Engi ne compartment: cover on the coola nt
expansio n tank

M N
0 <.J 'SI: ,...., \!) 1.1"1 ,...., 1.1"1 ,....,
Before you check anything in the engine com­
partment,
al ways r ead and heed all W ARN­
ING S r=;, A in Working in the engine compart­
ment on page 222.
.. Park your vehicle on a level surface.
.. Switch
off the ignition .
.. Read the eng ine coolant leve l from the cool­
ant expansion tank¢
fig. 191, ¢ page 224,
fig. 188.
With a cold engine, the coolant
level should be between the "min" and
"max" markings. When the engine is warm,
the leve l may be slightly above the "max"
mark ing .
The location of the coolant expans ion tank
can be seen in the engine compartment illus­
tration ¢
page 224.
To obta in an accurate read ing, the engine
must be switched
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
¢ page 16 will
illum inate until yo u add coolant and the level
has been restored to normal. Even though
there is an electric coo lant level sensor, we
still recommend you check the coolant leve l
from time to time .
Coolant loss
Coolant loss may indicate a lea k in the cooling
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 coola nt.
In a
sealed system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheat ing .
A WARNING
The coo ling system is unde r pressure and
c an get ve ry ho t. Reduce the risk of s cald­
ing from h ot coolan t by followi ng these
steps .
- T urn
off the engine and allow it to coo l
down.
Checkin g and fillin g 229
-Protect your face, hands and arms from
escaping flu id and steam by covering the
cap with a large, th ick rag.
- Turn the cap slowly and very carefully in
a counter-clockwise d irect ion while ap­
plying lig ht, downward pressure on the
top of the cap .
- To avo id being burned, do not sp ill anti­
freeze or coolant on the exhaust system
or hot engine parts. Under certa in cond i­
tions, th e 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 ve hicle's engine coolant. Add-
i ng radiator repa ir flui d may adverse ly af­
fe ct the funct ion a nd pe rfo rma nce of you r
co oling system and could re sult in damage
not covered by your New Vehicle Limi ted
War ranty.
Adding coolant
Be very careful when adding engine coolant.
Before you ch eck anyth ing in the eng ine com­
partment,
alway s re ad and heed all WARN­
INGS ¢ A in Working in the engine compar t­
ment on page 222.
.. Requirement: The re must be a residua l
amount of coolan t in the expansion ta nk
¢(D .
.. Tu rn off the engine.
.. Let the engine cool down.
.. Place a thick rag ove r th e coo lant expansion
tank
¢ page 228, fig . 191 and carefully
twist the cap counte r-clockwise ¢.&, .
.. Add coo lant m ixed in the correct ratio
¢
page 228, Coolant up to the MAX mark ­
ing .
.. Make s ure that the flu id leve l remains sta-
b le. Add more coo lant if ne cessary.
.. Twis t the cap o n again
t ightly.
Replacement engine coo lant must confo rm to
exact spec ificat ions
r=;, page 228, Coolant. ..,.
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