2021 AUDI Q2 ignition

Checking and topping up fluids
Selective catalytic
reduction (AdBLue/DEF)
General notes
Applies to: vehicles with selective catalytic reduction
On vehicles with selective catalytic reduction, a
urea solution (AdBLue/DEF) is injected into the
exhaust system upstream of
a
NOx catalytic
con­

verter in order to reduce nitrogen oxide emis­

sions.
The urea solution is known under the name
of AdBlue or DEF (Diesel Exhaust Fluid). The term
AdBlue is used below.
The AdBlue is held in a separate tank on the
vehi­

cle.
AdBlue consumption is approximately 1.0 -
2.5% of diesel fuel consumption.
As soon as a message appears in the instrument
cluster display reminding you to refill AdBlue,
you must refill the AdBlue tank or have this done
by
a
qualified workshop
^>page
293.
Checking the remaining range
The remaining (estimated) range for the current

AdBLue
level can be displayed on the on-board
computer:
- Vehicles with analogue instrument cluster

•=>
page 20.
- Vehicles with virtual cockpit*
<$page
19.
-The instrument cluster display will
tell
you
how far you can drive before the tank runs
dry
•=>page
292. If the AdBlue tank runs
dry, the engine cannot be started again af­
ter you switch off the ignition.
-The use of
AdBLue for
the operation of this
vehicle is required by Law.
Instrument cluster display
Applies to: vehicles with selective catalytic reduction

The
display informs you if the AdBlue level is too
low or if a system malfunction occurs.
Low AdBlue level
You will be informed if the amount of AdBlue in
the tank falls below a certain
Level.
Add at least
the minimum (smaller) amount of AdBlue

shown:

S
Refill x
I
- x
I
AdBlue. Range: x km
This message tells you the maximum distance

that
you can drive with the remaining amount of
AdBlue. Refill AdBLue.

3
Refill x
I
- x
I
AdBlue! No restart in x km! See
owner's manual
This message tells you the maximum distance
that you can drive with the remaining amount of
AdBlue. Refill AdBlue. Otherwise, after driving
the maximum distance and switching off the en­

gine,
you will not be able to restart the car.
| Refill x
I
- x
I
AdBlue! No restart. See own­
er's manual
This message appears when there is no more
AdBlue left in the tank. Refill AdBlue. Otherwise,
you will not be able to restart the car after you
switch off the engine.
When the AdBlue in the tank reaches the
mini­

mum
level,
you must add AdBlue
^>page
293,
Preparations.
Filling the wrong fluid / system fault
If
you
fill the AdBlue tank with a fluid other than
AdBlue and the system detects that the wrong
fluid has been added or there is a system fault, a
driver message will appear.

|
AdBlue:
system fault. No restart in x km!
See owner's manual
This message tells you the maximum distance

that
you can drive. Drive to a qualified workshop
and have the fault rectified. Otherwise, after driv­
ing the maximum distance and switching off the
engine, you will not be able to restart the car.
|
AdBlue:
system fault. No restart! See own­
er's manual
This message appears if the system detects that
the tank has been filled with the wrong fluid or if
there is a system fault. Drive to the nearest quali­
fied workshop without delay and have the fault

rectified.
Otherwise, you will not be able to re­
start the car after you switch off the engine.
292

Checking and topping up fluids
Preparations
Applies to: vehicles with selective catalytic reduction

CO

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Fig.
241 Vehicle as seen from the rear right: Unscrewing
the AdBlue cap
The AdBlue filler neck is located immediately be­
side the diesel filler neck. Add at least the
amount of AdBlue displayed in the instrument
cluster. If
you
do not refill this amount of
fluid,

the system may not detect that the tank has
been refilled and it may not be possible to restart
the engine. You can refill with a maximum of 12

litres.

Important: A message in the instrument cluster
display informs you if
you
need to refill AdBlue.

•
Park the vehicle on a level surface.

•
Switch off the ignition.
• Open the tank flap
<^>page
290.

•
Unscrew the cap on the filler neck
anti-clock­

wise
^>Fig.
241.

*•
Refill AdBlue from a filler nozzle
^>page
293,
canister
^>page
294 or bottle
^>page
294.
A WARNING
AdBlue can cause irritation to the
skin,
eyes,
and respiratory organs. Wash thoroughly with
clean water should you come into contact
with this
fluid.
Seek medical assistance if nee­

ded.

© CAUTION
- Use only
AdBLue
that complies with the ISO
22241-1 standard. Do not mix AdBlue with
additives and do not dilute it with water.
- AdBlue must not be added to the diesel
tank, and diesel must not be added to the
AdBlue tank. Never start the engine if you
fill up with the wrong type of
fuel,
as this
could damage the tank system and the en­

gine.
Obtain professional assistance.
-AdBlue attacks surfaces such as paintwork,
plastic veneer and carpets. Remove spilt
flu­

id as soon as possible with a damp cloth and
plenty of water. If the AdBlue has already

solidified,
use warm water and a sponge.
Residues of AdBlue solidify after
a
while if
they are not removed and can damage the
affected surface.
- Do not keep refill bottles or canisters in the
vehicle, as AdBlue can leak and damage the
vehicle interior.
- Keep AdBlue away from clothing. Wash
thoroughly with clean water should you
come into contact with this
fluid.

\J
Note
Please follow the AdBlue manufacturer's in­
structions for storage and use.
Refilling AdBlue from a filler nozzle
Applies to: vehicles with selective catalytic reduction

•
Open the tank flap
^>page
290.

*•
Unscrew the cap on the filler neck
anti-clock­

wise
^>page
293, Fig. 241.

*•
Fill up with AdBlue until the first time the filler
nozzle cuts off the supply
•=>(]}.

•
Put the tank cap back on
opage
294, After re­
filling.
CAUTION
- The handle of the filler nozzle must point
downwards when filling the tank. Otherwise
the filler nozzle will not cut off the supply
automatically
^0
in Preparations on
page 293.
- You should stop refilling the first time the
filler nozzle automatically cuts off the sup­
ply. Otherwise the level of AdBlue in the
tank may be too high and AdBlue could
overflow
<=>©
in Preparations on page 293.
293

Checking and topping up fluids
Refilling AdBlue from a canister
Applies to: vehicles with selective catalytic reduction

#

Fig.
242 Canister with screw-on hose
• Take the cap off the refill canister
o^/n
Prep­
arations on page 293,
<=>(T)
in Preparations on
page 293.

•
Screw the end of the hose (î) clockwise onto
the opening on the canister®.

•
Remove the cap
@
from the other end of the
hose®.

•
Fit the end of the hose (2) onto the filler neck
on the vehicle and turn clockwise as far as the
stop to secure.
• Lift the canister and then tilt it. Keep it tilted
until empty or until no more fluid runs into the
tank.

•
Remove the canister and screw the tank cap
back on
^>page
294, After refilling.
CAUTIO
Use only refill canisters of the correct type ap­
proved for your vehicle. AdBlue may Leak out
if
you
use another system.
© Note
- Your qualified workshop can tell you which
refill canisters are approved
for
your
vehi­

cle.

- Approved refill canisters contain about 5 li­
tres of AdBlue.
Refilling AdBlue from a bottle
Applies to: vehicles with selective catalytic reduction

•
Take the cap off the refill bottle
<=>^
in Prepa­
rations on page 293,
•=>(?)
in Preparations on
page 293.

•
Screw the bottle clockwise onto the filler neck
as far as it will go.

•
To empty the bottle, lightly press the bottom
of the bottle. Keep pressing the bottom of the
bottle until the bottle is empty, or until no
more fluid runs into the tank.

•
Remove the bottle and screw the tank cap back
on
<=>page
294, After refilling.
(J) CAUTION
Use only refill bottles of the correct type ap­
proved for your vehicle. AdBlue may leak out
if
you
use another system.
- Refill bottles are available from qualified
workshops.
- Approved refill bottles contain about 1.9 Li­
tres of AdBlue.
After refilling
Applies to: vehicles with selective catalytic reduction
Closing the filler neck

•
Screw the AdBlue cap clockwise onto the filler
neck until the AdBlue cap clicks audibly
•=> /\
in
Preparations on page 293,
^>(T)in
Prepara­
tions on page 293.

•
Press the left side of the flap to close it (you
should hear it click into place).
After refilling
The vehicle must be driven so that the system
can detect the AdBlue which has been added.
This process can take several minutes.
• If the AdBlue tank had run dry and a range of
0 km was shown on the display, switch on the
ignition for approx. 30 seconds before starting
the engine.
© Note
AdBlue can freeze in the tank at very Low
tem­

peratures. In this case, the system will not
detect AdBlue when you refill and will contin­
ue to indicate a Low
AdBLue
Level. The mes­
sage will disappear as soon as the tank has

thawed.

294

Checking and topping up fluids

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Emission controL
systems
Catalytic converter
Applies to: vehicles with petrol engine
The vehicle must only be used with unleaded pet­

rol,
otherwise the catalytic converter will be ir­
reparably damaged.
Never allow the fuel tank to run completely dry,
as the irregular supply of fuel can cause misfir­

ing.
This allows unburnt fuel to enter the exhaust

system,
which can cause overheating and dam­
age to the catalytic converter.
Diesel particulate filter
Applies to: vehicles with diesel engine
The diesel particulate filter can filter out almost
all soot particles contained in the exhaust gas. In
normal driving conditions the filter is self-clean­

ing.
Should the self-cleaning function of the filter
not be able to operate, e.g. when the vehicle is
continuously used only for short trips, the filter
becomes obstructed with soot and the indicator

lampnf°r
the
diesel particulate filter Lights up

cépage
34.
A WARNING
The exhaust system is very hot when the
vehi­

cle is being driven and after the engine has
been switched off.
- Never touch the tailpipes when they are hot
- risk of burns!
- Because of the high temperatures which can
occur in the emission controL system, do not
park the vehicle where the exhaust can
come into contact with flammable materials
under the car (e.g. on grass or at the forest
edge) - risk of fire!
- Do not apply any underseal agents in the
area around the exhaust system - risk of

fire!

Engine compartment
Working on components in the engine
compartment
Extra caution is necessary when working on com­
ponents in the engine compartment.
Always be aware of the danger of injury and
scalding as well as the risk of accident or fire
when working in the engine compartment (e.g.
when checking and refilling fluids). Always ob­
serve the warnings listed below and follow all
normal safety precautions. The engine compart­
ment of any motor vehicle is a potentially haz­
ardous area
oA-

A WARNING
- Switch off the engine.
-Switch off the ignition.

-Applythe
parking brake.
- On vehicles with manual gearbox place the
gear lever in neutral, on vehicles with auto­
matic gearbox move the selector lever to
position P.
- To avoid the risk of being scalded, never
open the bonnet if
you
see steam or coolant
escaping from the engine compartment.
Wait until no steam or coolant can be seen
before opening the bonnet.
- Wait for the engine to cool down.
- Keep children away from engine compart­
ment.
- Never spill fluids on a hot engine. These
flu­

ids can cause a fire (e.g. radiator
anti­

freeze).
- Take care not to cause short circuits in the
electrical system.
- When working in the engine compartment
be aware that the radiator fan may start
running suddenly, even if the ignition is
switched off - risk of injury!
- Do not unscrew the cap on the expansion
tank when the engine is hot. The cooling
system is under pressure.
- Protect face, hands and arms by covering
the cap with a large, thick rag to protect
against escaping coolant and steam.
295

Checking and topping up fluids
- Never remove the engine cover panel - risk
of burns!
- If any tests have to be performed with the
engine running, there is an extra safety risk
from the rotating parts, such as the drive

belts,
alternator and radiator
fan,
etc., and
from the high-voltage ignition system.
- Never touch the radiator fan. The electric
additional fan is controlled by temperature
and can start running without warning.
- Applies to vehicles with automatic gearbox:
Never open the throttle inadvertently (for
instance by hand from the engine compart­
ment) if
a
gear is engaged while the vehicle
is stationary with the engine running. The
vehicle will otherwise start moving immedi­
ately and could cause an accident.
- Observe the following additional warnings if
work on the fuel system or the electrical
system is necessary:
- Do not smoke.
- Never work near naked flames.
- Always keep an approved fire extinguisher
immediately available.
- Any work on the batteries and electrical sys­
tem in your vehicle entails a risk of injury
and chemical burns in addition to danger of
accident or fire.
For
this reason, you must
have the work carried out by
a
qualified
workshop.
© CAUTION
When topping up fluids make sure the correct
fluid is put into the correct filler opening. This
can otherwise cause serious malfunctions or
engine damage.
® For the sake of the environment
Inspect the ground underneath your vehicle
regularly so that any Leaks are detected at an
early stage. If
you
find spots of oil or other

fluids,
have your vehicle inspected in the
workshop.
© Note
located on the other side of the engine com­
partment.
Opening/closing the bonnet

The
bonnet is released from inside the vehicle.

Fig.
243 Detail of footwell on driver's side: Release lever

I

On right-hand drive vehicles* some of the
containers / reservoirs mentioned below are

Fig.
244 Unlocked bonnet: Lever
The wiper arms should be resting on the
wind­

screen:
make sure they are not in a raised
posi­

tion.
Otherwise the paint may get damaged.
Opening the bonnet

•
With the driver's door open, pull the lever un­
der the dashboard in the direction indicated
(arrow)
^>Fig.
243.

*•
Lift the bonnet slightly
•=> A-
•
Press the Lever under the bonnet in the direc­
tion indicated by the arrow
^>Fig.
244. This will
release the arrester hooks.

•
Open the bonnet.
Closing the bonnet
• To close the bonnet, pull it down to overcome
the spring pressure.

•
Then let it drop into the catches; do not press
down
|=>^.
•
296

Checking and topping up fluids
Coolant additive
The coolant additive contains anti-freeze and cor­
rosion protection agent. Only use one of the
fol­

lowing coolant additives. It is possible to mix
these additives.
Topping up coolant
Coolant additive
G13
G12++
Specification

TL774J

TL 774
G

The amount of coolant additive which needs to
be mixed with the water depends on the temper­
atures to be expected in the winter season. If the
anti-freeze concentration is too Low, the coolant
can freeze and cause engine damage.
Hot regions
Cold regions
Coolant
additive

min.
40%
max. 45 %

min.
50%
max. 55 %
Frost protec­
tion

min.-25°C

max. -40 °C

(T)
CAUTION
- Have your qualified workshop check the
cooling system before the winter season to
make sure that the anti-freeze concentra­
tion is adequate for the conditions to be ex­

pected.
This applies particularly if
you
drive
into a colder climate zone.
- To prevent damage to the engine, do not
use a different type of anti-freeze additive if
the approved type of additive is not availa­

ble.
In this case use only water and bring
the coolant concentration back up to the
correct level as soon as possible by putting
in the specified additive.
- Always top up with fresh, unused coolant.
- Radiator sealants must not be added to the
coolant.

Fig.
248 Engine compartment: Markings on coolant ex­
pansion tank
Please refer to the safety notes
^page
295,

Working on components in the engine compart­
ment.
Checking coolant level

•
Park the vehicle on a level surface.

•
Switch off the ignition.

•
Read off the coolant level on the coolant ex­
pansion tank
^>Fig.
248. When the engine is

cold,
the coolant level should be between the
marks. When the engine is warm, it may be
slightly above the top mark.
Topping up coolant
Important: The coolant expansion tank must not
be empty
•=>([).

•
Wait for the engine to cool down.

•
Cover the cap on the expansion tank with a

cloth,
and carefully unscrew the cap
anti-clock­

wise
<=>
/K.

*-
Add coolant in the correct concentration

tapage
299 up to the top mark.

•
You should make sure that the fluid level re­
mains stable. If necessary, add more coolant.

•
Screw the cap on again tightly.
Any loss of coolant normally indicates a Leak in
the cooling system. Drive to a qualified workshop
without delay and have the cooling system

checked.
If there are no leaks in the system, a
loss of coolant can only occur if the coolant boils
and is forced out of the system as a result of
overheating.
300

Checking and topping up fluids
A WARNING

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- The cooling system is under pressure. Do
not unscrew the cap on the expansion tank
when the engine is hot: you could be
scal­

ded by escaping steam.
- The coolant and coolant additive can be a
health hazard. Store the coolant additive in
the original container in a safe place out of
reach of children - risk of poisoning.
- When working in the engine compartment
be aware that the radiator fan may start
running suddenly, even if the ignition is
switched off- risk of injury!
Brake fluid
© CAUTION
Do not add coolant if the expansion tank is
empty. Air could have got into the cooling
system - risk of engine damage! In this case,
do NOT drive on. Obtain professional assis­

tance.

- Have your qualified workshop check the
cooling system before the winter season to
make sure that the anti-freeze concentra­
tion is adequate for the conditions to be ex­

pected.
This applies particularly if
you
drive
into a colder climate zone.
-To prevent damage to the engine, do not
use a different type of anti-freeze additive if
the approved type of additive is not availa­

ble.
In this case use only water and bring
the coolant concentration back up to the
correct level as soon as possible by putting
in the specified additive.
- Always top up with fresh, unused coolant.
- Radiator sealants must not be added to the
coolant.

ëB

k
DOT
4
A

•9
o
o
:>
li-

Fig.
249 Engine compartment: Cap of brake fluid reservoir
Please refer to the safety notes
^page
295,
Working on components in the engine compart­
ment.
Checking brake fluid level
Read off the brake fluid level on the brake fluid
reservoir
^>page
297, Fig. 245. The brake fluid
level must be between the MIN and MAX marks

<=>A.

The brake fluid
level
is also automatically moni­

tored.

In right-hand drive vehicles the brake fluid reser­
voir is on the other side of the engine compart­
ment.
Changing brake fluid
Have the brake fluid changed regularly by a quali­
fied workshop.
WARNING
-If the brake fluid Level is under the MIN
mark, the effectiveness of the brakes and
therefore the safety of the vehicle may be
impaired - risk of accident! Do not drive on.
Obtain professional assistance.
- Heavy use of the brakes may cause a vapour
lock if old brake fluid is left in the system.
This would seriously impair the effective­
ness of the brakes and the safety of the car
- risk of accident!
© CAUTION
- If the brake fluid level is above the MAX
mark, brake fluid may escape via the cap on •
301

Checking and topping up fluids
the reservoir in certain circumstances and
cause damage to the vehicle.
- Brake fluid must not be allowed to come in­
to contact with the vehicle's body, other­
wise it will attack the paintwork.

©
For the sake of the environment

1?
Batteries contain toxic substances including
sulphuric acid and
lead.
PLease contact a
qualified workshop if
you
have any questions.
Battery
General warnings for batteries
Because of the complexity of the power supply,
any battery work, such as disconnection, replace­
ment, etc. must be carried out by
a
qualified
workshop
^A-

The term "vehicle battery" refers to the 12 Volt
battery in your vehicle.
Explanation of warnings on vehicle battery:

m

Wear safety glasses!
Battery acid is extremely corrosive. Wear
protective gloves and safety glasses.

A

Keep open flames, sparks, uncovered
Lights and lit cigarettes away from the
battery!
A highly explosive mixture of gases may

~\
be given off when the battery is under
charge!
Keep children away from batteries and
battery
acid.

A WARNING
Any work on the batteries and electrical sys­
tem in your vehicLe entails a risk of injury and
chemical burns in addition to danger of
acci­

dent or fire. For this reason, you must have
the work carried out by a qualified workshop.
©
CA UTION

If the car is left standing for long periods,
protect the battery from frost. The battery
will be damaged irreparably if it is allowed to
freeze
^>page
303, Charging the vehicle
bat­

tery.

Vehicle battery

The
term "vehicle battery" refers to the 12 Volt
battery in your vehicle.
If the vehicle is not used for long periods
If
you
do not drive your vehicle for a period of
several days or weeks, the power management
will gradually shut off the on-board systems one
by one, or reduce the amount of current they are

using.
This limits the amount of power consumed
and helps to ensure reliable starting even after a
long period
^>page
149. Certain convenience fea­

tures,
such as interior lighting or electric seat ad­
justment, may not be available. These functions
will be restored when you switch on the ignition
and start the engine.
Even though some systems are deactivated auto­
matically, certain electrical equipment continues
to draw current even when the ignition is off. If
the vehicLe is left standing for long periods, this
can result in total battery discharge. If the
vehi­

cle battery is allowed to discharge completely, an
internal
chemicaL
reaction damages the battery
irreparably. To avoid this, the vehicle battery
should be recharged at Least once a month

^>page
303. PLease contact a qualified workshop
if
you
have any questions.
Winter conditions
Cold weather is very hard on the vehicle battery.
The starting capacity may be reduced as a result.
For this reason, you should have the vehicle bat­
tery checked by
a
qualified workshop before the
start of winter.
302