2021 AUDI A8 radiator

Driving


usual may increase the risk of accidents and
serious injuries.
— Secure the vehicle against rolling before ex-
iting the vehicle > page 108.

@) Note
— Avoid high engine speed, full throttle, and
heavy engine load if the engine has not
reached operating temperature yet. You
could damage the engine.
— If the engine has been under heavy load for
an extended period of time, heat builds up
in the engine compartment after the engine
is switched off and there is a risk of damag-
ing the engine. For this reason, let the en-
gine run at idle for approximately two mi-
nutes before shutting it off.
@ Tips
— Brief noises are normal when starting and
stopping the vehicle and are no cause for
concern.
— For up to 10 minutes after stopping the en-
gine, the radiator fan may turn on again au-
tomatically or it may continue to run, even if
the ignition is switched off.
— It may not be possible to start the vehicle in
extremely low temperatures.
— Power will be fully available once the engine
is at operating temperature.
Messages
Hj Engine start system: malfunction! Please
contact Service
Do not switch the ignition off because you may
not be able to switch it on again. Drive to an au-
thorized Audi dealer or authorized Audi Service
Facility immediately to have the malfunction cor-
rected.
B Engine start system: malfunction! Please
contact Service
There is a malfunction in the engine start system.
Drive immediately to an authorized Audi dealer
or authorized Audi Service Facility to have the
malfunction repaired.
108
B Remote control key: key not detected. Is the
key still in the vehicle?
The vehicle key was removed from the vehicle
while the engine is running. If the vehicle key is
no longer in the vehicle, you cannot switch the ig-
nition on or start the engine once you stop it. You
also cannot lock the vehicle from the outside.
Remote control key: hold back of key
against the designated area. See owner's man-
ual
The battery in the vehicle key may be drained or
there may be a malfunction. To start the vehicle,
you must also hold the vehicle key against the lo-
cation shown ?) > page 107, fig. 91.
If the malfunction remains, drive immediately to
an authorized Audi dealer or authorized Audi
Service Facility to have the malfunction correct-
ed.
When driving
Starting to drive, stopping, and parking
Starting from a stop
> Press and hold the brake pedal.
> Start the engine.
> Select a gear.
> Release the parking brake.
> Release the brake pedal. The vehicle may roll.
> Press the accelerator pedal to accelerate.
Securing the vehicle against rolling
Secure your vehicle to prevent it from rolling be-
fore exiting the vehicle.
> Set the parking brake.
> Select the “P” selector lever position.
> If parking on a steep road, turn the steering
wheel so that your vehicle will roll against the
curb in case it should start to move.
If one of these measures is not possible, for ex-
ample because there is no vehicle power, you
must secure your vehicle against rolling using ad-
ditional measures.
> Only park the vehicle on a level surface.
> Use suitable objects to block the front and rear
wheels.

Assist systems


surroundings directly and do not become dis-
tracted.

C) Note
— Obstacles may disappear from the measure-
ment range when approaching them, even if
they were already detected.
—Insome situations, the ability of the sen-
sors and cameras to detect and display cer-
tain objects may be limited.
— Objects located above the coverage area,
such as bumpers on parked cars, garage
doors that are partially open, or objects
that are hanging
— Low obstacles
— Narrow objects, such as barrier chains, fo-
liage, poles, or fences
— Projecting objects, such as trailer draw
bars
— Objects with certain surfaces and struc-
tures,
such as fabric
@) Tips
— The sensors and cameras and the areas
around them must not be obstructed be-
cause this can impair the function of the
systems that depend on them. Make sure
that the sensors and cameras are free of
snow, ice, and other deposits. Do not use
any accessories, stickers, or other objects
that extend into the range of the sensors
and cameras.
— On vehicles that have factory-installed li-
cense plate brackets on the front of the ve-
hicle, the brackets may only be replaced
with ones that are the same size and made
of the same material. Do not install any li-
cense plate brackets on the front of vehicles
that do not have factory-installed brackets.
Otherwise, the function of the system could
be impaired.
— The function of the sensors and cameras
may be limited when light and visibility con-
ditions are poor, for example when driving
into a tunnel, when there is glare, or when
there are reflective objects.
152
— External ultrasonic sensors, such as those in
other vehicles, can interfere with the sen-
sors.
— The coverage areas of the sensors > fig. 108
and cameras > fig. 109 are diagrams and do
not represent a true-to-scale image of the
sensor ranges.
— The system complies with United States FCC
regulations and ISED regulations
=> page 341.
Locations of the sensors and cameras


RAZ-0920



Fig. 110 Front area: sensors and cameras






Fig. 111 Rear area: sensors and cameras
Front area
Depending on the vehicle equipment, the follow-
ing sensors and cameras may be installed:
— Laser scanner in the front of the radiator grille
oA
— Camera behind the windshield
— Peripheral cameras on the exterior mirrors
— Front peripheral camera in the radiator grille
— Night vision camera in the radiator grille
— Front and side ultrasonic sensors
— Radar sensors at the front corners of the vehi-
cle
— Radar sensor in the front in the bumper

4N0012721BF
Driving information

After completing a lap, the difference between
the last lap and the previous best lap time will be
indicated with a “~” or “+”.
Pausing timing and displaying a split time
> To insert a pause @ select Pause in the menu.
> To resume timing, select Resume in the menu.
> To display a split time, select Split time in the
menu. The split time appears for approxi-
mately ten seconds in the instrument cluster.
The current lap timing will continue running.
Canceling lap timing
The timing of the current lap will stop. The lap
time will be erased and will not be included in the
statistics.
>» Select Cancel lap in the menu.
Resetting the time
> Select Reset lap times in the menu.
@ Tips
—A maximum of 99 lap times can be meas-
ured.
— If timing is paused, you can continue it later
even if you switch the ignition off.
— Saved lap times cannot be individually de-
leted from the total results.
— The saved lap timer values will remain after
switching the ignition off.
Lap stati
Applies to: vehicles with lap timer

Displaying lap statistics
You can display the number of laps driven ES
the fastest lap “+”, the slowest lap “~”, and the
average time “®” in the instrument cluster.
> Select in the instrument cluster: Vehicle func-
tions tab > I button > Lap statistics.
> Turn the thumbwheel down or up to display the
individual lap times.
> To return to the lap timing that was started, se-
lect the [J button > Lap times.
Resetting lap statistics
Requirement: the lap statistics menu must be
displayed.
> To reset the lap statistics, press and hold the
left thumbwheel until the message No lap
times have been recorded yet. appears.
@) Tips
The lap statistics list the lap times for the last
30 laps. The fastest and slowest lap times out
of up to 99 measured laps are also displayed.
Night vision assist
Applies to: vehicles with night vision assist
Night vision assist helps you when it is dark by
using an infrared camera to monitor the area in
front of your vehicle, within the limits of the sys-
tem. It can display objects up to a distance of ap-
proximately 1000 feet (300 m).
Pedestrian and wild animals are detected by
measuring the temperature difference between
the object and the background. Pedestrians and
wild animals will not be detected if the tempera-
ture difference is too small. The pedestrian and
wild animal marking feature is deactivated at
temperatures above approximately 77 °F (25 °C)
and when it is light outside.
The thermal image detected by the camera is dis-
played in the instrument cluster. Warm areas
generally appear lighter and cold areas appear
darker.
The camera for the night vision assist is located
in the vehicle's radiator grille > page 152. Make
sure the night vision camera is not covered by
stickers, deposits, or any other obstructions be-
cause this can impair the night vision assist func-
tion. Follow the information about cleaning
=> page 310.

ZX WARNING
— Observe the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 150. >

159

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


— Do not remove the engine cover under any
circumstances. This increases the risk of
burns.
— Due to the risk of electric shock, never touch
the ignition cable or other components in
the electronic high-voltage ignition system
when the engine is running or is starting.
— If a gear is engaged while the vehicle is sta-
tionary and the engine is running, do not
press the accelerator pedal inadvertently.
Pressing the accelerator pedal will cause the
vehicle to move, and this could result in an
accident.
— If inspections or repairs must be performed
while the engine is running, moving compo-
nents (such as the ribbed belt, generator,
and radiator fan) pose an additional risk.
— Set the parking brake first and select the
“P” (Park) selector lever position.
— Always make sure that no parts of the
body, jewelry, ties, loose clothing, and
long hair can be caught in moving engine
components. Before any work, always re-
move any jewelry and/or ties, tie back long
hair, and make sure all clothing fits close
to the body to reduce the risk of anything
becoming caught in engine components.
— Pay attention to the following warnings list-
ed when work on the fuel system or on the
electrical equipment is required.
— Do not smoke.
— Never work near open flames.
— Always have a working fire extinguisher
nearby.
— All work on the battery or electrical system
in your vehicle can result in injuries, chemi-
cal burns, accidents, or burns. Because of
this, all work must be performed only by an
authorized Audi dealer or authorized Audi
Service Facility.
— Limit your exposure to exhaust and chemi-
cals to as short a time as possible.

emit chemicals known to the State of Cali-
fornia to cause cancer and birth defects and
reproductive harm. In addition, certain flu-
ids contained in vehicles and certain prod-
ucts of component wear contain or emit
chemicals known to the State of California
to cause cancer and birth defects or other
reproductive harm.
— Battery posts, terminals and related acces-
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harms.
Wash hands after handling.



ZA WARNING
California Proposition 65 Warning:
— Engine exhaust, some of its constituents,
and certain vehicle components contain or

@) Note
When filling fluids, be sure not to add any flu-
ids to the wrong reservoirs. Otherwise severe
malfunctions and engine damage will occur.
@) For the sake of the environment
You should regularly check the ground under
your vehicle in order to detect leaks quickly. If
there are visible spots from oil or other fluids,
bring your vehicle to an authorized Audi deal-
er or authorized Audi Service Facility to be
checked.
275

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
>

4N0012721BF
Checking and Filling

> Close the cover on the positive terminal.
> Close the hood > page 276.

ZA WARNING
— Never connect a charging cable or jump
start cable directly to the 12 Volt vehicle
battery. Only use the connections in the en-
gine compartment > page 286.
— A highly explosive mixture of gases can form
when charging batteries. Only charge the
battery in well-ventilated areas.
— A drained battery can freeze at tempera-
tures around 32 °F (0 °C). Do not charge or
use a frozen or thawed battery. If ice forms,
the battery housing can crack and battery
electrolyte can leak out, which increases the
risk of an explosion and chemical burns.
Contact an authorized Audi dealer or author-
ized Audi Service Facility for more informa-
tion.
— Do not connect or disconnect the charging
cable while charging because this increases
the risk of an explosion.

@) Tips
Read all of the manufacturer's instructions
for the charger before charging the battery.
Windshield washer
system

B4M-0135)

Fig. 186 Engine compartment: washer fluid reservoir cap
Observe the safety precautions > page 274, Gen-
eral information.
The windshield washer reservoir <> contains the
cleaning solution for the windshield and the
headlight washer system* > fig. 186,
= page 277. The reservoir capacity can be found
in > page 344.
To reduce the risk of lime scale deposits on the
spray nozzles, use clean water with low amounts
of calcium. Always add window cleaner to the wa-
ter. When the outside temperatures are cold, an
anti-freezing agent should be added to the water
so that it does not freeze.
Messages
|} Please add washer fluid
Fill the washer fluid for the windshield washer
system and the headlight washer system* when
the ignition is switched off.
CG) Note
—The concentration of anti-freezing agent
must be adjusted to the vehicle operating
conditions and the climate. A concentration
that is too high can lead to vehicle damage.
— Never add radiator anti-freeze or other addi-
tives to the washer fluid.
— Do not use a glass cleaner that contains
paint solvents, because this could damage
the paint.
Service interval display
The service interval display detects when your ve-
hicle is due for service.
The service interval display works in two stages:
— Inspection or oil change reminder: after driv-
ing a certain distance, a message appears in the
instrument cluster display each time the igni-
tion is switched on or off. The remaining dis-
tance or time is displayed briefly.
— Inspection or oil change due: if your vehicle
has reached an inspection or oil change interval
or both intervals at the same time, the mes-
sage Inspection due! or Oil change due! or Oil
change and inspection due! appears briefly af-
ter switching the ignition on or off.
Checking service intervals
You can check the remaining distance or time un-
til the next oil change or next inspection in the
Infotainment system.
287