2012 AUDI A6 overheating

76 On the road
Cruise control
Switching on
Applies to vehicles: wit h crui se contro l
The cruise control system makes it possible to
drive at a constant speed starting at 20 mph
(30 km/h).
0
f
~
0
Fig. 75 Control lever with set b utto n
Fig. 76 Display: Selected speed
• Pull the lever to position @~ fig. 75 to
switch the system on.
• Drive at the speed you wish to set.
• Press button @to set that speed.
The stored speed and the indicator light
18;\0~1~ (US models)/ . (Canadian models) ap ­
pear in the instrument cluster display
~ fig. 76. The display may vary, depending on
the type of display in your vehicle . T he indica­
tor light
ll in the instrument cluster also illu­
minates.
This information is also shown briefly in the
Head-up Display* .
The speed is kept constant via an engine out­
put adjustment or active brake intervention.
A WARNING
-- Always pay attention to traffic even when
the cruise control is switched on. You are always responsible for your speed and
the distance between your vehicle and
other veh icles.
- For safety reasons, the cruise contro l
should not be used in the city, in stop­
and-go traffic , on twisting roads and
when road condit ions are poor (such as
ice, fog, gravel, heavy rain and hydro­
p laning) - risk of accident.
- Turn off the cruise control temporarily
when entering turn lanes, highway exit
lanes or in construction zones.
- Please note that inadvertently "resting"
your foot on the accelerator pedal causes the cruise control not to brake. This is
because the cruise control is overridden
by the driver's acceleration.
- If a brake system malfunction such as
overheating occurs when the cruise con­
trol system is switched on, the braking
function in the system may be switched
off. The other cruise control functions re­
main active as long as the indicator light
mmJI (US models)/ . (Canadian mod­
els) is on.
(D Tips
The brake lights illuminate as soon as the
brakes decelerate automatically .
Changing speed
Applies to vehicles: w ith cruise co ntrol
• Press lever in the 0 or 0 direct ion
~ page 76, fig. 75 to increase or decrease
your speed .
• Release the lever to save that speed.
Change speed in increments of 1 mph (1 km/
h) by lightly pressing the lever . If you keep the
lever pressed down, you will alter your speed
in 5 mph (10 km/h) increments.
You can also press the accelerator pedal down
to increase your speed, e.g . if you want to .,..

190 Intelligent technology
ESP includes and/or works together with the
anti-lock brake system (ABS), brake assist sys ­
tem, anti-slip regulation (ASR) , e lectronic dif­
f erential lock ( ED L) and e lectronic interax le
d ifferential lock* . ESP is switched on all the
time . In certain situat ions when you need less
traction , you can switch off ASR by pressing
the button
I!] c:;, page 191 , fig. 164 . Be sure
to switch ASR on again whe n you no longe r
need less tra ct ion.
Anti-lock braking system (ABS )
ABS prevents the wheels from locking up
when braking. The vehicle can still be steered
even du ring hard b rak ing . Apply steady p res­
sure to the brake pedal. Do no t pu mp the ped­
a l. A puls ing in the b ra ke ped al ind icates that
the system is he lp ing you to b rake the vehicle .
Brake assist system
The brake assist system can decrease brak ing
d ista nce. It increases braking power w hen the
d river p resses the brake pedal quic kly in eme r­
gen cy situa tions. You mus t press and hold the
b rake peda l until the si tuation is over. In veh i­
cles with adaptive cruise control*, the brake
assist system is more sensitive if the distance
detected to the vehicle ahead is too smal l.
Anti-slip r egulation (ASR)
ASR reduces engine power when the d rive
wheels begin to spin and adapts the fo rce to
the road conditions. This makes it easier to
start, accelerat e and drive up hills .
Electronic differential lock (EDL )
The ED L brakes wheels that are spinn ing and
transfers the drive power to the o ther d rive
wheel or whee ls i f th e vehi cle is equipped with
a ll-whee l drive *. This function is available up
to about 7S mph (120 km/h).
I n extreme cases, EDL automat ica lly switches
off to help keep the brake on the braked whee l
from overheating . EDL wi ll switch on again au­
tomatically when conditions have returned to
normal.
Electronic interaxle differential lock */
selective wheel torque control*
The electronic interaxle differential lock (front
whee l drive) or the se lective whee l torque
control (all-wheel dr ive) operates when d riv­
ing t hrough curves . The front wheel on the in­
s ide of the curve or both whee ls on the inside
of the curve a re b raked select ively as needed .
T his m inimizes sliding in th e front wheels and
allows for mo re p reci se d rivi ng throug h
c ur ves . The appl icable system may not acti­
vate when dr iving in we t or snowy conditions.
_& WARNING ~
- ESP , ABS, AS R, E DL and the e lectronic in­
terax le d iffe rential lock function* cannot
overcome the laws of physics . This is es­
pecially important on slippery or wet
roads. If the systems begin acti ng to sta­
b ili ze your ve hicle , you s hould immed i­
ately c hange yo ur speed to match the
road and traffic cond itions. Do not let
t he incre ased safety provide d by the se
systems tempt you to take risks. Do ing
so will increase the r is k of a loss of vehi­
cle control, collision and serious persona l
in jur ies.
-Always adapt your speed to road, traffic and weather conditions . The risk of los­
ing control of the vehicle increases when
driving too fast, espec ially through
curves and o n slippery or wet roads, and
when dr iv ing too close to vehicles up
ahead . ESP, ABS, the brake ass ist system,
E DL, ASR and the e lectronic interax le dif­
fe ren tial lo ck fu nction * can not prevent
coll is ions.
- Always ac celerate with spe cial care on
even, smooth s urfaces such as tho se th at
ar e we t or covered with i ce and snow.
The drive wheels can spin eve n with
these assistance systems t hat cannot al­
ways he lp to red uce the risk of loss of ve -
hicle control. ..,.

Catalytic converter
It is very important that your emission con­trol system (catalytic converter) is function­
ing properly to ensure that your vehicle is run­
ning in an environmentally sound manner .
.. Always use lead-free gasoline¢ page 215,
Fuel supply.
.,. Never run the tank down all the way to
empty.
.,. Never put too much motor oil in your en-
gine
¢ page 225, Adding engine oil~-
.,. Never try to push- or tow-start your veh icle.
The catalytic converter is an eff icient "clean­
up" device built into the exhaust system of
the vehicle . The catalytic converter burns
many of the pollutants in the exhaust gas be ­
fore they are released into the atmosphere.
The exclusive use of unleaded fuel is critically
importa nt for the life of the cata lytic convert­
e r and proper functioning of the engine.
A WARNING
-
- Do not park or operate the vehicle in
areas where the hot exhaust system may
come in contact with dry grass, brush,
fuel spill or other material which can cause a fire.
- Do not apply additional undercoating or
rustproofing on or near the exhaust
man ifold, exhaust pipes, catalytic con­
verter or heat shields. During driving, the
substance used for undercoating cou ld
overheat and cause a fire.
0 Note
- Be aware that just one tank filling with
leaded fuel will already seriously de­
grade the performance of the catalytic
converter.
- Do not exceed the correct engine oil level
¢ page 225.
-Do not drive until the fuel tank becomes
completely empty. The eng ine could mis­
fire . U nburned fuel could a lso get i nto
Dri vin g and en vironm ent 197
the exhaust system and this cou ld cause
the catalytic converter to overheat .
- Do not swi tch off the ignit ion while the
vehicle is mov ing.
- Do not continue to ope rate your veh icle
unde r these conditions, as othe rwise fuel
can reach the catalytic converter. This
co uld result in overheating o f the con­
verter, requir ing its replacement .
- To assure efficient operation of the Emis ­
sion Control System:
- H ave your vehicle maintained prope rly
and in accordance w ith the se rv ice rec­
ommendat ions in you r Warranty &
M aintenance boo klet.
- L ack of prope r maintenance as we ll as
improper use of the vehi cle w il l impair
the function of the em ission contro l
system and could lead to damage .
@ For the sake of the environment
Even when the Emiss ion Control System is
operat ing properly, the exha ust gas can
have a sul fur -li ke exhaust gas smell under
some operating states . This depends on
the sulfur content of the fuel being used .
Using a different brand of fue l may help,
or filling the tank with lead-free super
grade gasoline .
Avoid damaging the
vehicle
When you are drivi ng on poo r roads, or over
c ur bs, s teep ramps, etc., ma ke certai n that
low -lying parts s uch as spoilers and exhaust
system pa rts do not bottom o ut and get dam­
aged.
T h is is espec ially true for veh icles w ith low­
s lung chassis (spor ts chassis)* and fully load­
ed vehicles. •
•

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