2021 AUDI A8 cooling

4N0012721BF
Warm and cold

at low or high temperatures. You can adjust the
fragrance function > page 103.
Residual heat
The residual heat from the coolant is used to
heat the vehicle interior. To use this function,
press and hold the $8 button for more than two
seconds while the ignition is switched off. The
function switches off automatically after about
15 minutes.

Z\ WARNING
— You should not use the recirculation mode
for an extended period of time, because no
fresh air is drawn in and the windows can
fog when cooling mode is switched off. This
increases the risk of an accident.
— Individuals with reduced sensitivity to pain
or temperature could develop burns when
using the seat heating* function. To reduce
the risk of injury, these individuals should
not use seat heating*.



G) Note
To reduce the risk of damage to the seat heat-
ing* elements, do not kneel on the seats or
place heavy pressure on one area of the seat.
@ Tips
— If the front passenger's seat heating” is
turned on, it will not turn on again automat-
ically if more than 10 minutes have passed
between switching the ignition off and on
again.
— Only use the fragrance function* in modera-
tion and take any other passengers and ani-
mals into consideration when using the
function. An overlap of different scents or
odors could cause discomfort. If there is
discomfort, reduce the intensity or switch
the fragrance function* off. Only use fra-
grances that are approved by Audi.
Adjusting the vents
S| a g
S| = + a

Fig. 90 Cockpit and rear center console: adjusting the air
vents
You can open and close the air vents.
> Swipe right to open the air vents.
> Swipe left to close the air vents.
You can also press on the symbols directly to set
the air supply at a certain level or turn it off.
The levers adjust the direction of the airflow from
the vents.
Additional settings
You can adjust additional settings.
> Applies to: MMI: Select on the home screen:
VEHICLE > Air conditioning > ©.
Fragrance
Applies to: vehicles with fragrance function
Using Fragrance selection, you can select the fra-
grance and see the fill level of the fragrance.
You can select the strength of the scent with Fra-
grance level.
Footwell temperature*
You can adjust the footwell temperature for the
driver and front passenger.
Surface heating
Applies to: vehicles with surface heating
You can select if surfaces are also heated when
the seat heating is switched on. Other surfaces,
such as the door armrest and the center armrest,
may be heated, depending on the equipment.
103

4N0012721BF
Trailer towing

Trailer towing
Driving with a trailer
eT e e eeu)
Your vehicle is primarily intended for transport-
ing people and luggage. However, if you drive
with a trailer, follow the technical requirements,
the operation and driving tips, and the legal reg-
ulations.
Driving with a trailer affects the vehicle's energy
usage, performance, and wear. It also requires
higher concentration from the driver.

Z\ WARNING
Do not transport any people in a trailer due to
the risk of fatal injury.
Technical requirements
Trailer hitch

Only use a trailer hitch with a removable ball
hitch mount and ball hitch. The trailer hitch must
be permitted for the vehicle, the trailer and the
permitted total weight of the trailer being
pulled. Above all, it must be securely and safely
attached to the vehicle trailer.
Never mount a trailer hitch on the bumper. The
trailer hitch must be mounted in a way that does
not impair the function of the bumper. Do not
make any changes to the exhaust system and the
brake system.
Check regularly if the trailer hitch is securely
mounted. Always follow the instructions given by
the trailer hitch manufacturer.
Trailer brakes
If the trailer has its own brake system, then fol-
low the manufacturer specifications. However,
the brake system on the trailer must never be
connected to the vehicle brake system.
Engine cooling system
Driving with a trailer means a higher load on the
engine and the cooling system. The cooling sys-
tem must be designed for additional load and
contain enough coolant > @®.
CG) Note
Longer inclines cannot be driven without a
suitable cooling system, especially if the out-
side temperatures are high. Otherwise, this
increases the risk of engine damage.
Operating instructions
Towing capacity
Your vehicle can only be operated with class 1 or
class 2 trailers.
Load distribution
Poor cargo load and distribution can negatively
impact vehicle handling. Load the trailer based
on the following criteria as much as possible:
— Store objects in the vehicle luggage compart-
ment, if possible. The vehicle should always
carry the heaviest possible load and the trailer
should have the lightest possible load.
— Distribute the load in the trailer so that the
heavy objects are as close to the axle as possi-
ble.
— Secure objects so that they do not slide.
— Utilize the maximum permitted tongue weight
if possible.
Tires
Set the tire pressure on your vehicle for a “full
load”; see the tire pressure sticker > page 299. If
necessary, also adjust the tire pressure on the
trailer according to the manufacturer's specifica-
tions.
The trailer and the vehicle should be equipped
with winter tires when driving in winter tempera-
tures.
Outside mirrors
If you cannot see the traffic behind the trailer
with the standard exterior mirrors, then you
must attach additional exterior mirrors. Adjust
them so you have a sufficient visibility behind
you.
Exterior lighting
Follow the legal regulations for lighting on your
trailer that are applicable in the country where
147
>

Checking and Filling

cause overheating and damage to the catalytic
converter.
Malfunction Indicator Lamp (MIL)
If the S indicator light blinks or turns on, there
is a malfunction that is causing poor emissions
quality and that could damage the catalytic con-
verter. Drive slowly to an authorized Audi dealer
or authorized Audi Service Facility to have the
malfunction corrected.
The indicator light can also turn on if the fuel fill-
er cap is not closed correctly > page 271).
Engine compartment
General information
Special care is required if you are working in the
engine compartment
For work in the engine compartment, such as
checking and filling fluids, there is a risk of in-
jury, scalding, accidents, and burns. For this
reason, follow all the warnings and general
safety precautions provided in the following in-
formation. The engine compartment is a dan-
gerous area in the vehicle. > A.
Explanation of warnings (sticker in the engine
compartment):
®

Hot engine components!
Rotating parts!

The catalytic converter can be damaged
"127i if the oil level is too high!

Always follow the instructions in the op-
oA erating manual.



The radiator fan can switch on at any
i, time!

High voltage! Switch off the engine be-
5 fore coming into contact with any igni-
tion system components!



Applies to: vehicles with plug-in hybrid
drive: High voltage! The voltage in the
high-voltage system is high enough to
EN cause fatal injuries. Touching a damaged
high-voltage component can result in a
fatal electric shock.


D_ Depending on the engine and country
274

ZA\ WARNING
— Turn the engine off.
— Switch the ignition off.
— Set the parking brake.
— Select the “P” (Park) selector lever position.
— Allow the engine to cool.
— Keep children away from the engine com-
partment.
— Never spill fluids on a hot engine. These flu-
ids (such as the freeze protection contained
in the coolant) can catch fire.
— Avoid short circuits in the electrical system.
— Never reach into the radiator fan. The fan is
temperature-controlled and can turn on
suddenly, even when the ignition is switched
off.
— Never open the hood when there is steam or
coolant escaping from the engine compart-
ment, because there is a risk that you could
be burned. Wait until no steam or coolant is
escaping.
— Plug-in hybrid drive: The coolant expansion
tank cap is equipped with a seal that must
never be removed under any circumstances
= page 277, fig. 181. If the coolant expan-
sion tank for the high-voltage system is not
sealed, please contact an authorized Audi
dealer or authorized Audi Service Facility.
— Plug-in hybrid drive: The sealed cap must
only be opened by an authorized Audi dealer
or authorized Audi Service Facility.
—The cap on the coolant expansion tank must
never be opened when the coolant is hot.
The cooling system is under pressure. There
is a risk of burns
—To protect your face, hands, and arms from
hot steam or coolant, cover the cap with a
thick cloth when opening.

4N0012721BF
Checking and Filling

> Wait approximately two minutes.
» Applies to MMI: Select on the home screen: VE-
HICLE > Settings & Service > Oil level.
> Read the oil level in the display. Add engine oil
if the bar in the oil level indicator is just below
“min” > page 279.
@) Note
If the engine oil level is too low or too high,
there is a risk of engine damage.
@) Tips
The oil level indicator in the display is only an
informational display. If the oil level is too
low, a minimum oil warning appears in the in-
strument cluster. Add oil and close the hood.
The current oil level will be displayed on the
MMI the next time the ignition is switched on.
@) Tips
The engine oil consumption may be up to
0.5 quart/600 miles (0.5 liter/1,000 km), de-
pending on driving style and operating condi-
tions. Consumption may be higher during the
first 3,000 miles (5,000 km). The engine oil
level must be checked regularly. It is best to
check each time you refuel your vehicle and
before long drives.
— Because of the lubrication and cooling of
the engine, combustion engines consume
oil. The oil consumption varies depending
on the engine and may change during the
service life of the engine. Engines generally
consume more oil at the beginning during
the break-in period. Then oil consumption
stabilizes after the break-in period.
— Under normal conditions, oil consumption
depends on the quality and viscosity of the
oil, the engine RPM, the climate conditions,
and the road conditions. The dilution of oil
from condensation or fuel residue as well as
the age of the oil also play a role. Because
engine wear increases with mileage, oil con-
sumption will increase again over time until
it may be necessary to replace worn compo-
nents.
— Because all these variables play a role, it is
not possible to define an oil consumption
standard. Therefore, the oil level must be
checked regularly.
— If you believe that your engine has in-
creased its oil consumption, contact an au-
thorized Audi dealer or authorized Audi
Service Facility to determine the cause.
Please note that an exact oil consumption
measurement must be done with the neces-
sary care and accuracy and may take time.
An authorized Audi dealer or authorized
Audi Service Facility is trained in accurately
measuring the oil consumption.
— You can find information on engine oil and
engine oil capacities for the USA at www.
audiusa.com/help/maintenance, or for Can-
ada at www.audi.ca/ca/web/en/
customer-area/care-and-maintenance/
audi-service-schedules.html, or call
800-822-2834.
Adding engine oil

RAZ-0013|


Fig. 182 Engine compartment: engine oil filling opening
cover (example)
Observe the safety precautions > page 274, Gen-
eral information.
> Turn the engine off.
> Open the hood > page 276.
>» Unscrew the cap %~ for the engine oil filler
opening > fig. 182.
> Carefully add 0.5 quart (0.5 liter) of the correct
oil > page 277.
> Close the engine oil filler opening cap.
> Close the hood > page 276.
> Restart the ignition after two minutes and read
the current oil level in the MMI > page 278,
Checking the engine oil level.
279

4N0012721BF
Checking and Filling


— Drain the oil into a container designed for
this purpose that is large enough to hold the
full amount of oil in your engine.
— Engine oil is poisonous. Always store out of
reach of children.
— Prolonged contact of used engine oil with
the skin may cause skin damage. Always
wash oil off immediately with soap and wa-
ter to protect your skin.
@) Note
Do not mix any additives with the engine oil.
Additives may cause engine damage that is
not covered by your New Vehicle Limited War-
ranty.

@ For the sake of the environment
— Before changing the engine oil, make sure
you can dispose of the used engine oil cor-
rectly.
— Engine oil must always be disposed of cor-
rectly. Do not dump it in the yard, in the for-
est, or in open water, river channels, or sew-
ers.
— Have your used engine oil recycled by bring-
ing it to a used oil collection site or contact
a gas station.
Cooling system
The engine cooling system is filled with a mixture
of purified water and coolant additive at the fac-
tory. This coolant must not be not changed.
The coolant level is monitored using the Bg indi-
cator light. However, occasionally checking the
coolant level is recommended.
Messages
g& Turn off engine and check coolant level. See
owner's manual
The coolant level is too low.
Stop driving and switch the engine off. Check the
coolant level > page 282.
— If the coolant level is too low, add coolant
=> page 282. Only continue driving once the in-
dicator light turns off.
|_| Coolant temperature: too high. Please let
engine run while vehicle is stationary
Let the engine run at idle for a few minutes to
cool off, until the indicator light turns off.
— If the indicator light does not turn off, do not
continue driving the vehicle. See an authorized
Audi dealer or authorized Audi Service Facility
for assistance.
if Coolant system: malfunction! Please turn
off engine
Do not continue driving, shut the engine off, and
switch the ignition off.
— See an authorized Audi dealer or authorized
Audi Service Facility for assistance.
Applies to: vehicles with plug-in hybrid drive
B Electric drive: malfunction! Cooling system.
Please contact Service
There is a malfunction in the cooling system.
Drive to an authorized Audi dealer or authorized
Audi Service Facility immediately.
Coolant additive
The coolant additive is made of anti-freezing and
corrosion protection agents. Only add the follow-
ing coolant additives mixed with distilled water.

Coolant additive
Gl12evo
Specification
TL774L


The amount of coolant additive that needs to be
mixed with water depends on the climate where
the vehicle will be operated. If the coolant addi-
tive percentage is too low, the coolant can freeze
and damage the engine.


Coolant Freeze protec-
additive tion
Warm min. 40% min. -13 °F
regions max. 45% (-25 °C)
Cold min. 50% max. -40 °F
regions max. 55% (-40 °C) >

281

Checking and Filling

@) Note
— Before the start of winter, have an author-
ized Audi dealer or authorized Audi Service
Facility check if the coolant additive in your
vehicle matches the percentage appropriate
for the climate. This is especially important
when driving in colder climates.
— If the G12evo coolant additive is not availa-
ble in an emergency, do not add any other
additive. You could damage the engine. If
this happens, only use distilled water and
restore the correct mixture ratio with the
specified coolant additive as soon as possi-
ble.
— Only refill with new coolant.
— Radiator sealant must not be mixed with
the coolant.
— You can continue driving if the permitted
G12evo coolant additive was not added.
However, go to an authorized Audi dealer or
authorized Audi Service Facility immediately
to have the coolant replaced to reduce the
risk of engine damage.
— Due to the risk of engine damage, the cool-
ing system should only be refilled by an au-
thorized Audi dealer or authorized Audi
Service Facility. An authorized Audi dealer or
authorized Audi Service Facility can also pro-
vide you with important information about
the recommended coolant additive.

RAZ-0540

MIN


Fig. 183 Engine compartment - Coolant expansion tank:
@ cover with release button; @) markings
Observe the safety precautions > page 274, Gen-
eral information.
282
Applies to: vehicles with plug-in hybrid drive:
Your vehicle has two coolant expansion tanks
that are separate from each other > page 277,
fig. 181. One expansion tank for the combustion
engine and one tank for the high-voltage system.
The coolant expansion tank for the high-voltage
system is sealed and must not be opened > /\
and> A\.
Checking the coolant level
> Park the vehicle on a level surface.
> Switch the ignition off.
> Open the hood > page 276.
> Check the coolant level in the coolant expan-
sion tank > page 277, fig. 181 using the outer
markings (2) > fig. 183. The coolant level must
be between the markings (2) when the engine is
cold. When the engine is warm it can be slight-
ly above the upper marking.
> Conventional drive system: When you add cool-
ant to the expansion tank, please refer to
=> page 281, Cooling system.
>» Plug-in hybrid drive: If you add coolant to the
coolant expansion tank for the combustion en-
gine, see > page 281, Cooling system.
» Plug-in hybrid drive: If coolant is missing from
the high-voltage system coolant expansion
tank, do not continue driving. Contact an au-
thorized Audi dealer or authorized Audi Service
Facility immediately > A\.
Adding coolant
Applies to: coolant expansion tank for combustion engine
When adding coolant to the combustion engine
expansion tank, please observe the following in-
structions.
Requirement: there must be a residual amount of
coolant in the expansion tank >@).
If you must add coolant, use a mixture of water
and coolant additive. Audi recommends mixing
the coolant additive with distilled water.
> Allow the engine to cool.
> Place a large, thick towel on the coolant expan-
sion tank cap.
> Push the release button @ > fig. 183 on the
cap and carefully turn it to the left until you
feel resistance > /\.

4N0012721BF
Checking and Filling

> Push the release button again and remove the
cap completely.
> Add coolant mixed in the correct ratio
=> page 281 up to the MAX marking.
> Make sure that the fluid level remains stable.
Add more coolant if necessary.
> Turn the cap to the right to tighten it until you
feel resistance a second time.
Coolant loss usually indicates that there is a leak.
Immediately drive your vehicle to an authorized
Audi dealer or authorized Audi Service Facility
and have the cooling system inspected. If the
cooling system is not leaking, coolant loss can re-
sult from the coolant boiling due overheating
and then being forced out of the cooling system.

der any circumstances > page 277, fig. 181.
If the coolant expansion tank for the high-
voltage system is not sealed, please contact
an authorized Audi dealer or authorized
Audi Service Facility.
— When adding coolant, it may leak into the
inside of high-voltage components and
cause a short circuit, increasing the risk of

fire.


ZA WARNING
— The engine compartment in any vehicle is a
potentially dangerous area. Stop the engine,
switch the ignition off, and allow the engine
to cool before working in the engine com-
partment. Always follow the information
found in > page 274, General information.
— Never open the hood if you can see or hear
steam or coolant escaping from the engine
compartment. This increases the risk of
burns. The cooling system is under pressure.
When you no longer see or hear steam or
coolant escaping, you may open the engine
compartment with caution.
— When working in the engine compartment,
remember that the radiator fan can switch
on even if the ignition is switched off, which
increases the risk of injury.
— Coolant additive and coolant can be danger-
ous to your health. For this reason, store the
coolant in the original container and away
from children. There is a risk of poisoning.
CG) Note
Do not continue driving if the coolant expan-
sion tank is empty. Do not add any coolant,
because air could enter the cooling system
and damage the engine. See an authorized
Audi dealer or authorized Audi Service Facility
for assistance.
Brake fluid

BFV-0229|




ZA WARNING
Applies to: vehicles with plug-in hybrid drive
The coolant expansion tank for the high-volt-
age system may only be opened or filled by an
authorized Audi dealer or authorized Audi
Service Facility.
— The coolant expansion tank cap is equipped
with a seal that must never be removed un-


Fig. 184 Engine compartment: cap on brake fluid reservoir
Observe the safety precautions > page 274, Gen-
eral information.
Checking the brake fluid level
> Slide the cover that is located below the wind-
shield wipers on the driver's side toward the
windshield and remove the cover.
> Read the brake fluid level on the brake fluid res-
ervoir > page 277, fig. 181. The brake fluid lev-
el must be between the MIN and MAX markings
oA.
The brake fluid level is monitored automatically.
Messages
EG 7 @ Brakes: stop vehicle and check brake
fluid level
283
>

Fuses and bulbs








Fuse assignment - left side of cockpit
RAZ-0202

Fig. 210 Left side of the cockpit: fuse panel with plastic
clip






Fig. 211 Left side of the luggage compartment: fuse panel
with plastic clip
2 | Engine components 10 | Volume control
3 | Engine components 11 | Light switch, switch panels
4 |Engine components 12 | Steering column electronics
5 | Brake light sensor 14 | MMI Infotainment system control module
6 | Engine components 15 |Steering column adjustment
7 |Engine components 16 | Steering wheel heating
8 | Engine components
9 | Engine components ae ft side of the luggage
10 | Oil pressure sensor, oil temperature sensor (eelar|PEINE Ee
11 | Engine components g
12 | Engine components
13 | Engine cooling
14 | Engine control module, fuel injectors
15 | Engine sensors
16 | Fuel pump









330
No. Equipment No. | Equipment
Climate control system, interior air sensor 1_| Thermal management
2 | Audi phone box 5 |Air suspension/suspension control
Climate control system, fragrance system, 6 |Automatic transmission control module
3 particulate matter sensor 7 |Right rear seat adjustment
4 |Head-up display 8 | Rear seat heating
S_ |Audi music interface, USB input 9 |
Left tail light
6 |Instrument panel 10 | Front belt tensioner on driver's side
7 | Steering column lock
8 |Upper/lower display
9 |Instrument cluster