2018 AUDI A4 radiator

Driving
St ee ring lock1
)
The stee ring locks when you t urn the engine off
using the
! S T A RT ENGINE ST OP I button and
open the driver 's door. The locked steering helps
prevent v ehicle theft .
Emergency off function*
If it is abso lutely necessary, the engine can also
be turned off while dr iv ing at speeds star ting at
4 mph (7 km/h). To switch the eng ine off, press
the
! S TAR T ENGINE ST OP I button tw ice in a row
briefly or press and hold for longer than two sec­
onds.
A WARNING
- Never turn off the engine before the veh icle
has come to a comp lete stop . The full func­
t ion of the brake booster and the power
stee ring is not guaranteed. Yo u must use
more force to turn or b rake . Because you
cannot s teer an d brake as you usu ally
would, t his co uld lead to accidents and ser i­
ous in juries.
- Alw ays t ake the key wi th you w henever you
leave you r vehicle . Othe rw ise, the engi ne
cou ld be started o r electrical equipment
s uch as the power windows cou ld be operat­
ed . This can lead to se rious injury.
- For safety reasons, always park the vehicle
with the se lector lever in the P position
(a u­
tomat ic transmission) or with 1st gear en­
gaged (manual transmission). Otherwise
the vehicle could roll away u nintent ionally .
(D Note
If the eng ine has been under heavy load for
an extended per iod of t ime, heat builds up in
the engine compartment after the engine is
sw itched off and there is a risk of damaging
the engi ne . For this reason, let the engi ne run
for at idle for approximately two minutes
be­
fore shutting it off.
l) Th is fun ction is not avai la bl e in al l co un tries.
84
(D Tips
Fo r u p to 10 minutes after stopping the en­
g ine, the radiator fan may turn on again auto­
matically or it may continue to r un (even if
the ig nition is switched off) for the following
r easons:
- The coolant temperature is increas ing due
to trapped heat.
- If the eng ine is wa rm and the eng ine com­
partment a lso heats up from strong sun­
light .
- Applies to: vehicles with diesel particulate
filter: The emissions control system is heat­
ed through the regeneration process, even if
the engine has not reached its operat ing
tempe rature yet.
Messages
Engin e running . Warning! Turn off ignition be ­
fore leavin g vehicle
This message appears and a warning tone sounds
i f you open the drive r's door w hen the eng ine is
r un ning .
Applies to: vehicles with manual transmission
Please pres s clutch pedal
This message appears if you do not press the
clutch pedal to start the eng ine. The engine can
o nly be started w hen the clutch pedal is pressed.
Applies to: vehicles with automatic transmissions
Plea se pres s brake pedal
This message appears if you do not press the
bra ke peda l when sta rting t he eng ine .
Ill Remote control key : key not recognized. Is
the key still in the vehicle ?
This indicator light turns on and this message ap­
pears if the ignition key was removed from the
vehicle when the engine was running . If the igni­
tion key is no longer in the vehicle, you cannot
switch on the ignition or start the engine once

Parking systems
Parking systems
General information
A ppl ies to: ve hicles w ith a rea r parking sys te m /pa rking sys ­
tem p lus/rearv iew camera/peripheral ca meras
Depending on your vehicle's equipment , various
parking aids will help you when parking and ma­
neuvering.
The
rear parking system is an audible parking aid
that warns you of obstacles
behind the vehicle
¢ page 137.
The
parking system plus assists you when park ­
ing by audibly and visually indicating objects de­
tected
in front of and behind the veh icle
¢ page 137.
The
rearview camera shows the area behind the
vehicle in the Infotainment system display . The
lines in the rearview camera image help you to
park or
maneuver ¢ page 138. The parking sys­
tem plus functions are also available
¢ page 137.
The
peripheral cameras give various views to
help you when parking or maneuvering
¢ page 140. The parking system plus functions
are also available
¢page 137.
A WARNING ,..__ -
- Always look for traffic and check the area
around your vehicle by looking at it directly
as well. The parking system cannot replace
the driver's attention. The driver is always
responsible when entering or leaving a park­
ing space and during similar maneuvers.
- Please note that some surfaces , such as
clothing, are not detected by the system .
- Sensors and cameras have blind spots in
which people and objects cannot be detect­
ed . Be especially cautious of small children
and animals .
- Always keep your eyes on the vehicle's sur ­
roundings, using the rearview mirror as
well.
- The sensors can be displaced by impacts or
damage to the radiator grille, bumper,
wheel housing and the underbody. The park­ ing system may be impa ired as a result.
136
Have an authorized Audi dealer or author­
ized Audi Service Facility check their func­
tion.
(D Note
- Some objects are not detected or displayed
by the system under certain circumstances:
- objects such as barrier chains, trailer draw
bars, vertical poles or fences
- objects above the sensors such as wall ex ­
tensions
- objects with certain surfaces or structures
such as chain link fences or powder snow
- If you continue driving closer to a low ob­
ject, it may disappear from the sensor
range. Note that you will no longer be
warned about this obstacle.
- Keep enough distance from the curb to re ­
duce the risk of damage to the rims.
{i) Tips
- The system may provide a warning even
though there are no obstacles in the cover ­
age area in some situations, such as:
- certain road surfaces or when there is tall
grass
- external ultrasonic sources such as from
cleaning vehicles
-in heavy rain, snow, or thick vehicle ex­
haust
- We recommend that you practice parking in
a traffic-free location or parking lot to be­
come familiar with the system . When doing
this, there should be good light and weath­
er conditions.
- You can change the volume of the signals
and the display ¢
page 143.
- Please refer to the instructions for towing a
trailer located in
¢page 144.
- What appears in the infotainment display is
somewhat time-delayed.
- Th e sensors must be kept clean and free of
snow and ice for the parking aid to operate .
- Th e rearv iew camera is automatically
cleaned when cleaning the rear window*
¢ page 60 .

a co .... N ,....
N .... 0 0
3 co
Engine compartment
Working in the engine compartment
Special care is required if you are working in the
engine compartment
F or wo rk in th e en gine c ompar tment , suc h as
ch eckin g and fi llin g flu id s, th ere is a risk of in­
j u ry , sca lding , acci dent s, a nd b urn s. Fo r this
re aso n, follow all the warnin gs and ge nera l
safet y pr eca uti ons pr ov ided in the follow ing in ­
form ation . Th e e ng ine c ompartm en t is a d an­
ger ous a re a .
~ ,&. .
_& WARNING
- T urn the engine off.
- Switch the ign ition off .
- Set the parking brake .
- Shift the gearshift lever to neutral in vehicles with a manual transm ission and se­
lect the P selector lever posit ion in vehicles
with an automatic transmission .
- Let the engine coo l down.
- Never open the hood when there is steam or coolant escaping from the eng ine compart­
ment, because there is a risk that you cou ld
be burned . Wait until no steam or coolant is
escaping.
- Keep children away from the engine com­
partment.
- Never spill flu ids on a hot engine. These flu­
ids (such as the anti-freezing agent con­
tained in the coolant) can ignite.
- Avoid sho rt circu its in the e lectrical system.
- When working in the engine compartment,
remember that the radiator fan can sw itch
on even if the ign ition is switched off , which
increases the risk of inj ury .
- Never open the cap on the coolant expan­
sion tank when the eng ine is warm. The
cooling system is under press ure.
- T o protect your face, hands, and arms from
hot steam or coolant, cover the cap with a
large cloth when opening.
- Do not remove the eng ine cover under any
c ircumstances . This increases the risk of
burns .
Check ing and Filling
-If tests need to be performed with the en­
gine running, there is add itiona l danger due
to mov ing components (such as the ribbed
belt, alternator and radiator fan) and from
the high-voltage ignition system.
-Do not under any circumstances activate the
throttle inadvertently (for example, by hand
from the engine compartment) if the veh i­
cle is stat ionary but the eng ine is running
and a gea r is engaged. Otherwise, the veh i­
cle will start to move immed iate ly and this
could result in an accident.
- Pay attent ion to the following warn ings
when wor k on the fue l system is required :
- Do not smoke.
- Never work near open flames.
-Always have a working fi re 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
o nly by an
author iz ed Audi dealer or author iz ed Audi
Serv ice Facility.
-To reduce the r isk of electric shock and in­
jury, never touch the following components
when the engine is runn ing or is being start­
ed:
- Ign ition cable
- Other components in the e lectronic high-
vo ltage ign ition system
-I f you must check or perform wo rk on the
engine wh ile it is running:
-First, set the parking brake and and move
the gearshift lever to neutral (for manual
transm issions) or select the P selector lev­
er position (for automatic transm iss ions).
- Always proceed w ith extreme caution so
that clothing, jewelry or long hair do not become caught in the radiator fan, fan
belt or other moving components or do
not come into contact with hot compo­
nents. Tie bac k long hair befo re beginning
work and do not wear clothing that can hang down into the engine.
-Lim it your exposure to exhaust and chemi­
cals to as short a time as possible
¢ .&. .
32 3

areas, into open streams or down sewage
drains.
- Recycle used engine oil by taking it to a used
engine oil collection facility in your area, or
contact a service stat ion .
Cooling system
Coolant
The engine coo ling 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 through
the. in­
dicator light
¢ page 30. However , we do recom­
mend occasiona lly checking the coolant level
manually.
If you must add coolant, use a mixture of water
and coolant addit ive. Mixing the coolant additive
with distilled water is recommended.
Coolant additive
The coolant additive is made of anti -freezing and
corrosion protection agents. Only use the fol low­
ing coolant additives . These additives may be
mixed with each other.
Coolant additive Specification
G13
TL 774 J
G12++ TL
774 G
The amount of coo lant 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 °()
Cold min.
50% max
. -40 °F
regions max.
55% (-40 °()
(D Note
-
Before the start of winter, have an author­
ized Audi dealer or authorized Audi Service
Facility check if the coolant additive in your
Checking and Filling
vehicle matches the percentage appropriate
for the climate. This is especia lly important
when driving in colder climates.
- If the appropriate coo lant additive is not
available in an emergency, do not add any
other additive. You could damage the en­
gine. If this happens, only use water and re­
store the correct mixture ratio with the
specified coolant add itive as soon as poss i­
ble .
- Only refill w ith new coolant.
- Radiator sealant must not be mixed with
the coolant.
Adding coolant
Fig. 270 E ngine compartment: re lease button on coolant
expansion tank
Observe the safety precautions ¢,&. in Working
in the engine compartment on page 323.
Checking the engine coolant level
.. Park the vehicle on a level surface .
.. Switch the ignition off .
.. Read the coolant level on the coolant expansion
tank
¢ fig. 270.
.. The coolant level must be between the MIN and
MAX markings when the engine in co ld. When
the engine is warm it can be slightly above the
MAX marking.
Adding coolant
.. Let the eng ine cool down .
.. Place a cloth over the coolant expansion tank
cap .
.. Push the release button ¢ fig. 2 70 and carefu l­
ly unscrew the cap to the left until you feel re-
sistance¢ ,A. IIJ,-
329

Checking and Filling
.,. Push the release button again and remove the
cap comp lete ly .
.,. Make sure that the fluid level rema ins stable.
Add more coolant if necessary .
.,. Turn the cap to the right to secure it until you
feel resistance a second t ime.
Coolant loss usually indicates there is a leak . Im ­
mediately drive your vehicle to an authorized
Audi dealer or authorized Audi Serv ice Facility
and have the cooling system inspected . If the
coo ling system is not leaking, a loss can come
from the coolant boiling through overheating
and being pushed out of the cool ing system.
_& WARNING
- T he coo ling system is under pressure. Do
not open the coolant expansion tank cap
when the engine is hot. This increases the
risk of burns.
- The coo lant add itive and the coolant can be
dangerous to your healt h. For this reason,
keep the coolant in the origina l container
and away from children. There is a risk of poison ing.
- When working in the engine compartment, remember that the radiator fan can switch
on even if the ign ition is switc hed off, which
increases the risk of in jury.
(D Note
Do not add coolant if the expansion tank is
empty. There may be air in the cooling sys­
tem, wh ic h increases the risk of engine dam­
age.
If th is is the case, do not continue dr iv­
ing . See an a uthorized Aud i dea le r or author­
ized Aud i Service Fa cil ity fo r assistance.
330
Brake fluid
Fig. 271 En gine compa rtment: cap o n brake fluid reservo ir
Observe the safety precautions¢.&, in Working
in the engine compartment on page 32 3 .
Check ing the brake fluid level
.,. Read the brake fluid level on the brake fluid
reservoir ¢ page 325, fig . 268 . The brake flu id
level must be between the MI N and MAX ma rk­
ings ¢.&, .
The brake f lu id level is monito red automatically.
Changing the brake fluid
Have the brake fluid changed regularly by an au­
thorized Audi dea ler or authorized Audi Service
Facility.
_& WARNING -
- If the brake flu id leve l is below the MIN
marking, it ca n impair the brak ing effect
and driving safety, wh ich increase the r isk of
an accident. Do not continue dr iv ing . See an
author ized Audi dealer or au thori zed Audi
Serv ice Facility fo r ass ist ance.
- I f the brake fl uid is old, b ubbles may form
in the bra ke system dur ing heavy bra king.
This wo uld im pair b raking per formance and
driving safety, which increases the risk of an
accident.
- To ensure the brake system functions cor­
rectly, only use bra ke fluids tha t comp ly
wit h VW standard 50 1 14 or
FMVSS- 116 DOT 4 .
(D Note
-If the bra ke f lu id leve l is ab ove the MAX
marking, bra ke fluid may le ak o ut over the

Checking and Filling
Charging the vehicle battery
Fig. 272 Engine co mpa rtment : connec tors for a c harger
and jump start cab le s
Req uirement: only use chargers with a m aximum
c hargi ng vo lta ge of 30 amp s/14.8 Volt s.
The
vehicle battery cables remain connected .
.,. Read the warnings c> .&. in General warnings
about batteries on page 331
and c> ,&. .
.,. Switch off the ignition and all electrical equip ­
ment .
.,. Open the hood 9 page 324 .
.,. Open the red cover on the positive terminal
c>fig. 272 .
.,. Clamp the charger terminal clamps to the jump
s ta rt pin s
according to the instruct ions . (pin
under the red cover = "positive ", p in with hex­
agonal head= "negative ") .
.,. Inse rt the powe r cable for the charg ing device
i nto the socke t and switch the dev ice on .
.,. At the end of the charging process , switch the
charger off and pull the power cab le out of the
socket .
.,. Remove the charger terminal clamps.
.,. Close the red cover on the positive terminal.
.,. Close the hood c> page 324 .
A WARNING
-A highly explosive mixtu re of gases can form
when cha rging batter ies. On ly charge the
vehicle batte ry in well-ven tilated areas.
- A drai ned vehicle battery can freeze at tem­
peratu res a round 32
QF (0 QC). A froze n or
thawed veh icle bat tery must not be charged
and must not be used anymore. The ba ttery
housing can crac k and battery acid can leak
o ut if ice forms, wh ich increases the r isk of
an exp losion and chemical burns. Contact an
332
author ized Audi dealer or authorized A udi
Service Facility for more information.
- Do not connect or disconnect the charging
cable whi le charging because this increases
the risk of an explos ion.
@ Tips
- Only charge the vehicle battery t hrough the
connect ions in the engine compartme nt.
- Read all of the manufacturer's instructions
for the charger before charging the vehicle
battery.
Windshield washer system
Fi g. 2 7 3 Engine compar tm ent: washer flui d res ervoir cap
The windshield washer fluid reservoir¢ contains
t he cleaning solution for the windshield and th e
headlight washer system *
c> page 325, fig. 268 .
The reservoir capaci ty can be found in
c> page 381.
To reduce the risk of lime scale deposits on the
spray no zzles, use clean water with low amounts
of calcium . Always add w indow 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 .
(D Note
-The concentration o f ant i-freez ing agent
must be adjusted to the ve hicle operat ing
conditions in the respective climate . A con­
cent ration t hat is too high can lead to vehi­
cl e damage.
- Never add radiator anti-freeze or other addi­
t ives to the washer fluid.

a co .... N ,....
N .... 0 0
3 co
Fuse panel @ (brown)
No . Equipment
2
Mass airflow sensor, camshaft adjust-
ment, charge air cooler pump
3 Exhaust doors, fuel injectors, radiator inlet
4 Vacuum pump, hot water pump, particu-
late sensor, biodiesel sensor
5 Brake light sensor
6 Engine va lves, camshaft adjustment
7
Heated oxygen sensor, mass airflow sen-
sor
8
Water pump, high pressure pump, high
pressure regulator va lve
9 Hot water pump
10
Oil pressure sensor, oil temperature sen-
sor
11 Clutch pedal position sensor
12 Engine valves
13 Radiator fan
14 Fuel injectors
15 Ignition coils
16 Fuel pump
Fuse panel @ (red)
No . Equipment
1 Anti-theft alarm system
2 Eng ine control module
3 Lumbar support
Automatic transmission selector mecha -
4
nism
5 Horn
6 Electromechanical park ing brake
7 Gateway control module
8 Interior headliner lights
10 Airbag control module
11 Electronic Stabilization Control (ESC)
12 Diagnostic connector, light/rain sensor
13 Climate control system
14 Right front door control module
15 A/C compressor
Fuses and bulbs
Fuse panel © (black)
No . Equipment
1 Front seat heating
2 Windshield wipers
3 Left head light electronics
4
Panorama glass roof I sliding/t ilting sun-
roof
5 L eft front door control module
6 Sockets
7 Right rear door control module
8 All wheel drive
9 Right headlight electronics
10
Windshield washer system/headlight
washer system
11 Left rear door control module
Fuse panel @ (black)
No. Equipment
Seat ventilation, rearv iew mirror, climate
1 control system, rear climate control sys-
tern controls, windshield defogger
2 Gateway, climate control system
3 Sound actuator/exhaust sound tuning
4 Clutch pedal posit ion sensor
5 Engine start
7 Rear USB charg ing port
8 Homelink
9 Adaptive cruise contro l
11 Video camera
12 Matrix LED headlight/right LED headlight
13 Matrix LED headlight/left LED headlight
14 Rear window wipe r
Fuse panel © (red)
No . Equipment
1 Ignition coils
5 En gine mount
6 Automat ic transmission
7 Instrument panel
8 Climate control system (blower)
10 Dynamic steering
11 Engine start
371