2018 AUDI A4 Control

Airbag system
In addition to their normal safety function, safe­
ty belts help keep the driver or front passenger in
position in a frontal collision so that the airbags
can provide supplemental protection.
The airbag system is not a substitute for your
safety belt. Rather, it is part of the overa ll occu­
pant restraint system in your vehicle. Always re­
member that the airbag system can only help to
protect you if you are wearing your safety belt
and wearing it properly . This is why you should
always wear your safety belt, not just because
the law requires you to do so ¢
page 263, Gener­
al information.
Remember too, airbags will deploy only once and
only in certain k inds of accidents - your safety
belts are always there to offer protection in those
accidents in which airbags are not supposed to
deploy or when they have already deployed, for
examp le when your vehicle str ikes or is struck by
another after the first collision .
This is jus t one of the reasons why an airbag is
not a substitute for the safety belt. The a irbag
system works most effectively when used with
the safety belts. Therefore, always wear your
safety belts correct ly.
It is important to remember that while the sup­
p lemental knee airbag system is designed to re­
duce the likelihood of serious injuries, other inju ­
ries, for example, swe lling, bruising and minor
abrasions and friction burns can also occur when
an airbag inf lates .
The knee airbag system basically consists of:
- T he electronic control module
- T wo inflatab le airbags (airbag and gas genera-
to r), one for the driver and one for the front
pass enger
- The airbag indicator ligh t in the instrument
panel
The knee airbag system will not deploy:
-whe n the ignition is switched off
- in frontal collisions when the deceleration
measured by the control un it is too low
- in side collisions
- in rea r-end collisions
288
-in rollovers
- in the event of a system malfunction (warning/
ind icator light is on)
¢page 32 .
A WARNING
-Safety belts and the airbag system can only
provide protection when occupants are in
the proper seating
position ¢ page 281 .
-If the airbag indicator light ¢ page 32
comes when the veh icle is being used, have
the system inspected immediately by your
author ized Audi dealer. It is possible that
the airbag will inflate when it is not sup­
posed to, or will not inflate when it should.
How knee airbags work
The risk of injury to the leg area con be reduced
by fully inflated knee airbags.
Fig. 243 In flated a irbags protect ing in a fro nta l coll ision
The knee airbag system has been designed so
that the airbags for the dr iver and front passen­
ger dep loy in certain but not all fronta l collisions .
If the front airbags deploy, the knee airbags also
deploy in frontal collisions when the deployment
threshold stored in the control unit is met .
When the system deploys, the airbags fill with a
prope llant gas, and inflate between the lower
part of the instrument panel and the driver and
the lower part of the instrument panel and the
front passenger
¢page 281, fig. 240 .
Although they are not a soft pillow, they can
"cushion" the impact and in this way they can
help to reduce the risk of injury to the lower ex­
tremities.

Airbag system
the occupant sitting next to it is not seated prop­
erly. The side airbag for the front passenger seat
can be used with properly installed child re­
straints. Please be sure to read the important in­
formation and warnings whenever using a child
restraint in a vehicle: Safety belts
Qpage 263,
Airbag system Qpage 271, Ch ild safety
c::;, page 295.
The side airbag system basically consists of:
-the e lectronic control modu le and externa l side
impact sensors
- the two side airbags located in the sides of the
front backrests
- two rear side airbags*
- the airbag warning light in the inst rument clus -
ter.
The airbag system is monitored electronically to make certa in that it is functioning properly at all
times. Each time you turn on the ign it ion, the air­
bag system indicator light will come on for a few
seconds (self diagnostics).
The side airbag system supplements the safety
be lts and can help to reduce the risk of injury to
the driver's, front and rear* passenger 's upper
torso on the side of the vehicle that is struck in a
side co llision. The a irbag dep loys only in side im­
pacts and on ly when the vehicle acceleration reg­
istered by the control unit is high enough . If this
rate is below the reference value programmed in­
to the control un it, the side airbags will not be
tr iggered, even though the car may be badly
damaged as a result of the collision.
It is not pos­
sib le to define an a irbag tr igger ing range that
will cover every possible angle of impact, since
the circumstances will vary considerably between
one collision and another . Important factors in­
clude, for example, the nature (hard or soft) of
the impacting object, the angle of impact, vehicle
speed, etc.
Q page 291, Important safety in­
structions on the side airbag system.
Aside from their normal safety function, safety be lts work to help keep the driver or front pas­
senger in pos it ion in the event of a s ide collision
so that the side a irbags can provide protection.
The airbag system is
not a subst itute for your
safety belt. Rather, it is part of the overall occu-
290
pant res traint system in your vehicle . Always re­
member that the side airbag system can only
help to protect you if you are wear ing your safety
belt and wearing it properly. This is another rea­
son why you should a lways wear your safety
belts, not just because the law requires you to do
soc::;, page 263, General information .
It is important to remember that while the sup­
plemental side airbag system is designed to re­
duce the likelihood of ser ious injuries, other inju­
ries, for example, swelling, bru is ing, friction
burns and minor abrasions can also be assoc iated
with deployed side airbags. Remember too, side
a irbags w ill dep loy only once and only in certa in
kinds of accidents
-your safety belts are always
there to
offer protection.
Vehicle damage, repair costs or even the lack of
vehicle damage are not necessarily an ind icat ion
of over-sens itive or fa iled airbag activation. In
some collisions, both front and side airbags may
inflate. Remember too, that airbags wi ll deploy
on ly once and only in certain kinds of collisions
-
your safety be lts are always there to offer protec­
tion in those accidents in which airbags are not
supposed to deploy or when they have already
deployed .
The side airbag system will not deploy:
- when the ignition is turned off
- in side co llisions when the acceleration meas -
ured by the sensor is too low
- in front-end collisions
- in rea r-end collisions
- in rollovers.
In some types of accidents the front airbags, side
curta in airbags and side a irbags may be triggered
together .
&_ WARNING
-Safety belts and the airbag system will only
provide protection when occupants are in
the proper seating position
Q page 291.
- If the airbag indicato r light Q page 32
comes when the vehicle is being used, have
the system inspected immediately by your
authorized Audi dealer. It is possible that

Airbag syste m
by being pushed into you as the airbag in­
flates.
- Never p lace or attach accessories or other
objects (such as cupho lders, te lephone
brackets, or even large, bulky objects) on
the doors, over or near the area marked
"AIRBAG" on the seat backrests.
- Such objects and accessories can become
dangerous projectiles and cause in ju ry
when the supplemental side airbag de­ ploys.
- Never carry any objects or pets in the de­ ployment space between them and the
airbags or allow children or other passen­
gers to travel in this posit ion.
- Always use the built-in coat hooks* only for
lightweight clothing. Never leave any heavy
or sharp-edged objects in the pockets that
may interfere w it h side airbag deployment
and can cause personal i njury in an accident.
- Always prevent the side airbags from being
damaged by heavy objects knocking against
or hitting the sides of the seatbacks.
- The airbag system can only be triggered
once. If the airbag has been triggered, the
system must be replaced by an author ized
Audi dealership.
- Damage (cracks, deep scratches etc.) to the
orig inal seat covers or to the seam in the
area of the side a irbag mod ule m ust always
be repa ired immed iate ly by an authorized
Audi dealer .
-If children are sea ted improperly, their r is k
of injury increases in the ca se of an ac ciden t
¢ page 295, Child safety .
-Never attempt to modify any components of
the a irbag sys tem in any way.
- In a side collision, side a irbags w il l not fu nc­
t ion properly if sensors cannot correct ly
measure increasi ng air pressure ins ide the
doo rs when air escapes through larger, un­
closed openings in the door panel.
- Never drive w ith inter io r door tr im panels
removed .
- Never drive when parts have been re­
moved from the inside doo r panel and the
open ings they leave have not been proper­
ly closed.
292
- Never drive when loudspeakers in the
doors have been removed unless the
speaker holes have been properly closed.
- Always make certain that openings are
covered or filled if additional speakers or
other equipment is installed i n the inside
door panels.
- Always have work on the doors done by an
authorized Aud i dealer or q ualified work­
shop.
Side curtain airbags
Description of side curtain airbags
The side curtain airbags can provide supplemen­
tal protection to properly restrained oc cupants.
Fig. 2 46 Sid e curta in airbags, driver 's side : locatio n
The side curtain airbags are located on both sides
of the interior above the front and rear side win­
dows
¢ fig. 246.
The side curtain airbags contain features that
provide ejection mitigation to help prevent vehi­
cle occupants or parts of their bodies from be ing
completely or part ially ejected from the vehicle
i nterior i n certa in side impacts and vehicle roll­
ove rs .
The side curtain airbag system supplements the
safety belts and can help to reduce the risk of in­
jury for occupants' heads and upper torso in a
side collision . The s ide curtain a irbag inflates in
s ide impacts and on ly when the veh icle ac celera­
tion registered by the control unit is high
eno ugh . If this ra te is be low the refere nce va lue
programmed into the contro l unit, the side cur ­
tain airbag will not be triggered, even though the
car may be badly damaged as a result of the
..,_

collision. It is not possible to define an airbag
triggering range that will cover every possible
an­
g le of impact, s ince the circumstances will vary
considerably between one collision and another.
Important factors include, for example, the
na­
ture (hard or soft) of the impacting object, the
angle of impact, vehicle speed, etc.
¢ page 293,
How side curtain airbags work .
Aside from their normal safety function, safety
be lts work to he lp keep the driver or front pas­
senger in pos it ion in the event of a collision so
that the side curtain airbags can p rovide protec­
tion .
The airbag system is not a substitute for your
safety belt . Rather, it is part of the overall occu­
pant restraint system in your veh icle . Always
re­
member that the airbag system can only help to
p rotect you if you are wearing your safety bel t
and wearing it properly . This is another reason
why you should always wear your safety belts, not just because the law requires you to do so
¢ page 263, General information.
It is important to remember that whi le the s ide
curtain airbag system is designed to he lp reduce
the likelihood of serious injuries, other injuries,
for example, swelling, bruising, friction burns and minor abrasions can also be associated with
these airbags upon deployment . Remember too,
these airbags will deploy only o nce and only in
certa in ki nds of acc idents -your safety belts are
always there to offer protection .
The side curtain airba g sy stem ba sically
consists of:
- The electronic control module and external s ide
impact senso rs
- The side curtain airbags above the w indows of
the outer seating positions with ejection miti­
gation feat ures
- The airbag indicator light in the instrument
panel
The airbag system is monitored electronically to make certain it is funct ion ing properly at all
times . Each time you turn on the ignit ion, the air­
bag system ind icator light will come on for a few
seconds (self d iagnost ics) .
Airb ag sys tem
The side curta in airbag is not activ ated:
- if the ignition is turned off
- in side co llisions whe n the acceleration meas-
ured by the sensor is too low
- in rear-end col lisions .
_&. WARNING
-Safe ty bel ts and the airbag system will only
provide pro tect ion when occupants are in
the proper seating position
¢ page 65,
Front seats.
- I f the airbag ind ic a tor light q page 3 2
comes when the veh icle is being used, have
the system inspected immediately by your
authorized Audi dealer. It is possib le that
the airbag will inflate when it is not sup­
posed to, or w ill not inf late when it should.
How side curtain airbags work
Side curtain airbags con work together with side
airbags to help reduce the risk of head and upper torso injuries for occupants who are properly re­
strained .
Fig. 24 7 Illustration of pr incip le: Inflated s ide curta in air­
bags o n the left s ide
The side curtain airbags inflate between the oc­
cupant and the w indows in a side collis ion
c> fig . 247 .
When the system is triggered, the side curtain
airbag is filled with propellant gas and breaks
through a seam above the front and rear side
windows identified by the AIRBAG label. In order
to help provide this additional protect ion, the
s ide curtain a irbag must inf late w ithi n the blink
of a n eye at very high speed and with g reat fo rce .
T he side c urtain airbag could injure you if yo ur
Ill>
293

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Checking and Filling
Gasoline
Fuel supply
Applies to: veh icles with gaso line engine
Using the right fuel helps keep the environment
clean and prevents engine damage .
Fuel recommendation
The fuel recommended for your vehicle is unlead­
ed premium
grade gasoline. Audi recommends
using TOP TIER Detergent Gasoline with a mini­
mum octane rating of 91 AKI (95 RON). For more
information on TOP TIER Detergent Gasoline,
p lease go to the official website
(www.toptiergas .com) .
The recommended gasoline octane rating for
your engine can also be found on a label located
on the inside of the fuel filler flap . This rating
may be specified as AKI or RON.
Your vehicle may also be operated using unlead­
ed regular gasoline with a min imum octane rat ­
ing of 87 AKl/91 RON. However, using 87 AKl/91
RON octane fuel will slightly reduce engine pe r­
formance.
Use unleaded gasoline only. Unleaded gasoline
is available throughout the USA , Canada, and in
most European countries . We recommend that
you do not take your vehicle to areas or countries
where un leaded gasol ine may not be available.
For more information on refueling your vehicle,
see
c::> page 317 .
Octane rating
Octane rating indicates a gasoline's ability to re­
sist engine damaging "knock" caused by prema­
ture ignit ion and detonation . Therefore , buy ing
the correct grade of gasoline is very important to
h e lp prevent possible engine damage and a loss
of eng ine performance.
Gasoline most commonly used in the United
States and Canada has the following octane rat­
ings that can usually be found on the filler pump:
- Premium Grade: 91
-96 AKI
Checking and Filling
-Regu lar Grade: 87 -90 AKI
E xplanation of the abb reviations:
AKI =
Anti Knock Index = (R +M)/2 = (RON +MON)/
2
RON = R esearch Octane Number
MON = Motor Octane Number.
(D Note
- Do not use any fuel w ith octane ratings low­
er than 87 AKI or 91 RON otherwise expen­
sive engine damage w ill occur .
- Do
not us e leaded gasoline. The use of lead­
ed gasoline will severe ly damage your vehi­
cle's catalytic converter and its ability to
control exhaust emissions .
Blended gasoline
Applies to: vehicles with gasoline engine
Use of gasoline containing alcohol or MTBE
(methyl tertiary butyl ether)
You may use unleaded gasoline blended with al­
cohol or MTB E (commonly referred to as oxygen ­
ates) if the blended mixture meets the following
criteria:
Blend of gasoline methanol (wood alcohol or
methyl alcohol)
-Anti -knock index must be 87 AKI or higher.
- Blend must contain no more than 3% metha-
nol.
- Blend must contain more than 2% co-solvents.
Blend of gasoline and ethanol (grain alcohol or
ethyl alcohol)
- Anti-knock index must be 87 AKI or higher.
- Blend must not conta in more than 15% etha-
nol.
Blend of gasoline and MTBE
- Anti-knock index must be 87 AK I or higher.
- Blend must contain not more than 15% MTBE.
Seasonally adjusted gasoline
Many gasoline grades are blended to perform es­
pecially well for winter or summer dr iving . Dur-
ing seasonal change-over, we suggest that you
..,.
315

Checking and Filling
fill up at busy gas stations where the seasonal
adjustm ent is more likely to be mad e in time.
0 Note
- Methanol fuels which do not meet these re­
quirements may cause corrosion and dam­
age to plastic and rubber components in the
fuel system.
- Do not use fuels that fail to meet the speci­
fied criteria in this chapter .
- If you are unable to determine whether or
not a particular fuel blend meets the speci­
fications, ask your service station or its fuel
supplier.
- Do not use fuel for which the contents can­
not be identified.
- Fuel system damage and performance prob­
lems resulting from the use of fuels differ­
ent from those specified are not the respon­
sibility of Audi and are not covered under
the New Vehicle or the Emission Control
System Warranties.
- If you experience a loss of fuel economy or
driveability and performance problems due
to the use of one of these fuel blends, we
recommend that you switch to unblended
fuel.
Gasoline additives
Applies to: vehicles with gasoline engine
A major concern among many auto manufactur­
ers is carbon deposit build-up caused by the type
of gasoline you use .
Although gasoline grades differ from one manu­
facturer to another, they have certain things in
common. All gasoline grades contain substances
that can cause deposits to collect on vital engine parts, such as fuel injectors and intake valves.
Al­
though most gasoline brands include additives to keep engine and fuel systems clean, they are not
equally effective .
Audi recommends using TOP TIER Detergent Gas­
oline. For more information on TOP TIER Deter­
gent Gasoline, please go to the official website (www.toptiergas .com) .
316
After an extended period of using inadequate
fuels, built-up carbon deposits can rob your
en­
gine of peak performance.
([) Note
- Damage or malfunction due to poor fuel
quality is not covered by the Audi New Vehi­
cle Limited Warranty.
- Do not add aftermarket fuel additive prod­
ucts to your fuel tank.
Diesel fuel
Applies to: vehicles with diesel engine
Always use ULSD (Ultra Low Sulfur Diesel) No. 2.
The ULSD No. 2 meets the ASTM 0975.
Diesel fuel with concentrations of biodiesel high­
er than 5
% such as 811,820 or 8100 are strictly
prohibited.
Service station fuel pumps are labeled with the
correct fuel information for easy recognition by
the user. If the diesel fuel pump is not labeled
ask the station operator what fuel is being dis­
pensed before filling up your vehicle.
ULSD No. 2 may not be available outside the USA
and Canada. Be sure to check before traveling to
other countries.
ULSD No. 2 can become thicker in very cold tem­
peratures, and this can impair the engine's start­
ing and running . Depending on the season , gas
stations provide ULSD No. 2 that flows better in
cold temperatures so that you can continue oper­
ating your vehicle as usual.
(D Note
- Your vehicle's diesel engine was designed
soley for use with ULSD No. 2. Therefore,
never use gasoline, heating oil, other fuels
or flow improvers. These contain substances
that will severely damage the fuel system
and the engine. Such damage will not be
covered by your New Vehicle Limited War­
ranty.
- If you put any amount of incorrect fuel in
the fuel tank, do not start the engine under
.,..

Check ing and F illing
"' Position the bottle on the filler tube and turn
the bottle clockwise unti l it stops turning.
"' Press lightly aga inst the bottom of the bott le
to empty it. Continue pressing the bottom of
the bottle until it is empty or unti l fluid stops
flowing into the tank .
"' Remove the bottle and seal the filler neck
¢ page 322, Completing AdBlue refill .
0 Note
Only use refill bottles that are approved for
your vehicle. Us ing other systems can ca use
Ad Blue to leak.
-You can obta in refill bottles from an author­
i zed Audi dealer or authorized A udi Service
F ac ility.
- A pe rm itted refill bottle conta ins approxi­
mately 0 .5 gallon ( 1.9 liters) of Ad Blue.
Completing AdBlue refill
Applies to: vehicles with selective catalytic reduction
Closing the filler neck
"'Turn the Ad Blue cap to the r ight on the filler
tube unti l th e cap cl ic k s into
p lace ¢.&. in
Prepara tion on page 320,
¢ (Din Preparation
on page 320 ..
"' Then press on the left side of the tank door un-
ti l it latches.
After filling
The vehicle must be driven so tha t the system
recognizes t hat the Ad B lue was refilled. This can
t ake severa l m in utes.
"' If there was no Ad Blue left in the tank and a
r ange of O mi (0 km) was shown in the d isplay,
swi tch the ign ition on fo r abo ut 30 seconds be­
f ore star ting the engine .
(D Tips
Ad Blue in the tank can free ze at very low tem­
pera tures. If this happens, the system will
not detect that the AdB lue was refilled and it
w ill contin ue to inform you of the low AdBlue
322
leve l. The message tu rns off as soon as the
tank thaws out again .
Emissions control
systems
Cat alytic converter
Applies to: vehicles with gasoline engines
T he vehicle may only be driven w ith un leaded
gaso line, otherwise the catalytic converter will be
destroyed .
Never drive unti l the tan k is comp lete ly empty .
T he irregu lar supply of fuel that resu lts from that
can cause eng ine misfires. Uncombusted fuel will
enter the exhaust system , which can cause over­
heating and damage to the catalytic converte r.
Di esel particulate filt er
Applies to: vehicles with diesel engines
The diese l particulate filter filters nearly all of
the soot part icles out of the exhaust. The filter
cleans itself automat ica lly under norma l dr iv ing
cond it io ns. If the filter cannot clean itself (for ex­
amp le, because yo u are on ly driving short distan ­
ces), the filter becomes clogged with soot and
the
1111 i ndicato r light for the diese l particulate
filte r tu rns
on ¢ page 33.
_&. WARNING
The tempera ture o f the e xhaust sys tem is
h igh, both when driving and a fter stopping
the engine.
-
-Never tou ch the e xhaus t tail p ipes o nce they
have become hot. This cou ld resu lt in burns.
-D o not p ark your vehicle over flamm able
materials such as grass or leaves because
the hig h temperature of the emissions con­
trol system (catalyt ic converter or d iese l
pa rticu late filter) co uld start a fire.
- Do not apply underbody protectant in the
exhaust system area, beca use this increases
the risk of f ire.

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(D Note
Driving with an insufficient oil level is likely to
cause severe damage to the engine.
@ Tips
-The oil pressure warning display. is not
an indicator of the oil level. Do not rely on
it. Instead, check the oil level in your en­
gine at regular intervals, preferably each
time you refuel, and always before going
on a long trip.
-If you have the impression your engine con­
sumes excessive amounts of oil, we recom­
mend that you consult an authorized Audi
dealer to have the cause of your concern
properly diagnosed. Keep in mind that the
accurate measurement of oil consumption
requires great care and may take some
time. An authorized Audi dealer has instruc­
tions about how to measure oil consump­
tion accurately.
Checking the engine oil level and adding
engine oil
The engine oil level can be checked in the Info ­
tainment system
Fig. 269 Engine compa rtment: eng ine oil filler opening
cove r
Checking the engine oil level
- Park the vehicle on a level surface.
- Shut the engine off when it is warm.
0 N
-N
" 00 IX)
-Switch only the ignition back on. Wait approxi-
mately two minutes so that the engine oil can
flow back into the oil pan .
Checking and Filling
- Select in the Infotainment system: the !MENUI
button > Vehicle > left control button > Service
& checks > Oil level.
-Check the oil level in the Infotainment system
display. Add engine oil if the bar in the oil level
indicator is just before "min".
Adding engine oil Follow the safety precautions
~&. in Working in
the engine compartment on page 323.
- Stop the engine and open the hood
~page 324 .
-Unscrew the cap~ on the engine oil filling
opening
~ fig. 269, Qpage 325.
- Carefully add O .S quart (O .S liter) of the correct
oil
~ page 325.
- Close the engine oil filler opening cap.
- Close the hood, restart the ignition after two
minutes and read the current oil level in the In ­
fotainment system.
A WARNING ...__ --When adding oil, do not let oil drip onto hot
engine components. This increases the risk
of afire.
-You must secure the cap on the oil filler
opening correctly so that oil does not leak
out onto the hot engine and exhaust system
when the engine is running, because this is
a fire hazard.
-Always clean skin thoroughly if it comes into
contact with engine oil.
0 Note
- The engine oil level must not be under the
"min" marking, because this increases the
risk of engine damage.
- If the message II Please reduce oil level
appears, there is too much oil in the engine
and there is a risk of damaging the catalytic
converter and engine. Do not start the en­
gine. Contact an authorized Audi dealer or
authorized Audi Service Facility to have ex­
cess engine oil extracted if necessary.
- Do not mix any additional lubricants into
the engine oil. Damage caused by such addi-
tives is not covered by the warranty.
IJJ>
327