2015 AUDI A4 check engine

216 Checking and filling
-If you have the impression your engine
consumes excessive amounts of oi l, we
recommend that you consult an author­
ized 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 instructions about how to
measure oil consumpt ion accurately.
Checking the engine oil level
Fig. 183 MMI D isp lay : Oil leve l ind icator
Read oil level
.,. Park your vehicle so that it is horizonta lly
level.
.,. Shut the engine off when it is at operat ing
temperature .
.,. Switch only the ignition back on.
• Wait approx . two minutes.
• Se lect : Fu nct ion button
I _C_A_R_I > Oil level. Or
.,. Select : Function button
ICARI > Car sys-
tems* control button > Servicing & checks >
Oil level.
.,. Read the oil Level in the MMI* Display
c:> fig. 183. Add engine oi l if the bar of the
oil level indicator is near "min"
c:> page 216
Depend ing on the way the vehicle is driven
and the operating conditions, oil consumpt ion
can be up to a 1/2 quart per 600 mi les (0.5
li­
ter per 1,000 km) . Consumption may be high­
er within the first 3,000 miles (5 ,000 km).
(D Tips
The oil Level indicator in the MMI* Display
is only an information display . If the oil
Level is too Low, a minimum oil warning ap -pears in
the instrument cluster. Add oil
c:> page 216. If the hood has been opened,
the current oil level is shown in the instru­
ment cluster the next t ime the ignition is
switched on.
'e:;1: Adding engine oil
Fig. 184 Engin e compar tmen t: Cover on th e oil filler
neck
.,. Before you check anything in the engine
compartment,
always read and heed all
WARNINGS c:> .&. in Working in the engine
compartment on page 212 .
.,. Shut the engine off .
.,. Unscrew the cap
't'::71 to the engine oi l filling
hole
¢ fig. 184, c:>page 214, fig. 182 .
.,. Carefully top off with 0 .5 quarts (0 .5 liters)
of the appropriate oil
c:> page 214 .
• Check the oil level again after two minutes
r::;, page 216, Checking the engine ail level .
.,. Top off the oil aga in , if necessary .
.,. Screw the cap back on the filling hole .
_& WARNING
-While topping off, the oil must not come
i n contact with hot engine parts -fire
hazard!
- The oil filler cap must be properly se­
cured to prevent oil from being sprayed
on the hot engine and exhaust system
when the engine is running -fire hazard!
- If your skin has come in contact with the
engine o il, you must subsequently
cleanse it thoroughly.
(D Note
- Check the oil level using the radio or
MMI*. If the message Please reduce oil

"" N
0 ::.,: co ,...., \!) 1.1'1 ,...., 1.1'1 ,....,
level appears, contact your authorized
A udi dealer or qualified workshop to
have excess oil ext racted if necessary.
- Audi does not recommend the use of oil
additi ves. They may damage the engine
and ad ve rsely affect your New Vehicle
Warranty.
@) For the sake of the environment
- Under no circ umstances ca n the o il come
i n contact with the sewage network or
the soil.
- Observe and fo llow lega l regu lations
when disposing of empty oil containers.
Changing the engine oil
We recommend thot hove your oil changed by
an authori zed Audi dealer or a qualified serv­
ice station .
Before you c hec k anything in the engine com ­
pa rtment,
always read and heed all WARN ­
INGS
c:> A in Working in the engine compart­
ment on page 212.
The engine oil must be changed according to the intervals specified in your Warra nty
&
Maintenance book let . This is very important
beca use the l ubricating properties of oil di­
minish gradua lly dur ing normal veh icle use .
Unde r some c irc umstances the engine o il
should be changed more frequently . Change
oil more often if you drive m ost ly short dis­
tances, operate the vehicle in dusty areas or
u nder predominantly stop-and-go t raff ic con­
d it ions, or have your veh icle w her e tempera­
tures rema in below free zing fo r ex tended pe­
rio ds.
Detergent add itives in the o il w ill mak e fresh
oil look da rk after the eng ine has been run­
ni ng fo r a shor t time. This is norma l and is not
a reason to ch an ge the oi l mo re often th an
recommended.
B ecause of the prob lem of prope r dispos al,
a long w ith the spe cial tools and necessary ex­
pe rti se require d, we strong ly recommend tha t
Checkin g and fillin g 217
you have your oil changed by an a uthorized
Audi deale r or a qualified service station.
If you choo se to change your oil your self ,
please note the fo llow ing important info rma­
t ion :
A WARNING
To reduce the risk of pe rsonal i njury if you
must change the eng ine oil in yo ur vehicle
yourself:
- Wear eye protect ion .
- To reduce t he risk of burns from hot en -
gine oil, let the engine coo l down to the
touch .
- W hen removi ng the oil dra in plug with
your fingers, stay as fa r away as possib le .
A lways keep your fo rearm parallel to the
groun d to help p revent hot o il from run­
ning down you r arm .
- Dra in the oil into a c ontaine r designed
for this purpose, one large enough to hold at least the tota l amount of oi l in
your engin e.
- Eng ine oil is poison ous. Keep it we ll out
of the reach of childre n.
- Continu ous contact wit h used eng ine oi l
is harmful to yo ur sk in. Always protect
your skin by washi ng oil off tho ro ughly
w it h soap and wate r.
(J) Note
Neve r mix oil additives with yo ur engine
oi l. These additives can damage your en­
g in e and adversely affect you r Aud i Limit­
ed New Veh icle Warranty.
@ For the sake of the environment
-Before changi ng your oil, first make su re
you know where you ca n prope rly dispose
of the us ed oil.
- Always disp ose of used eng ine o il proper­
ly . D o not dump it on garde n soil, wood­
e d ar eas, into op en st reams o r down
sewage drain s.
- Recycle used engi ne oil by taking it to a
used eng ine oil collect io n facility in you r
a rea, or contact a service sta tio n.
•
•

218 Check ing and filling
Engine cooling system
Coolant
The engine coolant performs two functions: it
keeps the engine from overheating and it pro ­
tects the engine from freezing in the winter .
The cooling system is sealed and generally re­
quires little attention.
The cooling system has been filled at the fac­
tory with a permanent coolant which does not need to be changed. The coolant consists of a
mixture of specially conditioned water and the
manufacturer's glycol-basedcoolant addi-
tive G13 antifreeze with ant icorrosion addi­
tives (50% for USA models; 60% for Canadian models) . This mixture both assures the neces­
sary frost protection and protects metal com­
ponents in the engine's cooling system from
corrosion and scaling.
It a lso raises the boil­
ing point of the coo lant.
Do not reduce the concentration of the coo l­
ant in the summer by adding plain water .
The
pr opor tion of coolant add itiv e m ust be at
l eas t 50% but not more than 60%
to main­
tain antifree ze protection and cooling efficien­
cy. If the coolant frost protection is too low,
the coolant could freeze and damage the veh i­
cle heating and eng ine cooling system .
For year-round driving, antifree ze is added at
the factory for temperatures down to:
- -31°F(-35°C)USA
- - 40 ° F ( - 40 °C) Canada.
I f you must add coo lant, use a m ixture of wa­
ter and coolant addit ive. M ixing the coolant
addit ive with dist illed water is recommended.
_& WARNING
Before you check anything in the engine
compartment, always read and heed all
WARNINGS
~ &. in Working in the engine
compartment on page 212.
(D Note
- Before winter sets in, have the coolant
checked to see if the coolant additive in
-
your vehicle is sufficient to meet the cli­mate conditions . This is especia lly impor­
tant if you live in a reg ion where the win­
ter is extreme ly cold. If necessary, in­
crease the proportion of coolant additive
to 60% .
- When adding coolant additive to your
cooling system, remember :
- We recommend us ing on ly coolant ad­
d itive G12 ++ or G13 for your vehicle.
This coolant addit ive is availab le at a u­
thorized Audi dealers. Other types of
antifreeze can significantly reduce cor­ rosion protection. The resulting corro­
sion can cause a loss of coolant and se­
rious engine damage .
- Do not add any type of radiator leak seal­
ant to your vehicle's engine coolant.
Add ing radiator repa ir flu id may adverse ­
ly affect the function and performance of
your cooling system and could resu lt in
damage not covered by your New Veh icle
Limited Warranty.
Checking the engine coolant level
The engine coolant level can be checked with
a quick glance.
F ig . 1 85 Engine compar tmen t: Cover on the coo la n t
expans io n t ank
.,. Before you check anything in the engine
compa rtment,
alwa ys read and h eed all
W ARNING S ~ ,& in Working in the engine
compartment on page 212.
.,. Park your vehicle on a level surface .
.,. Turn off the ignition.
.,. Read the engine coolant level from the coo l­
ant expansion tank
c:> fig . 185, c:> page 214,
fig . 182.
With a cold engine, the coolant Iii>-

'"" N
0 ::.,: co ,...., \!) ..,.,
,...., ..,., ,....,
level should be between the "MIN" and
"MAX" markings. When the engine is warm,
the level may be slightly above the "MAX"
marking .
The location of the coolant expansion tank
can be seen in the engine compartment illus­
tration
<=> page 214.
To obtain an accurate reading , the engine
must be switched
off.
The expansion tank in your vehicle is equipped
with an electric coolant level sensor.
When the coolant level is too low, the warning
light in the Auto-Check System <=>
page 17 will
blink until you add coolant and the level has
been restored to normal. Even though there is
an electric coolant level sensor, we still rec­
ommend you check the coolant level from
time to time.
Coolant loss
Coolant loss may indicate a leak in the cooling
system. In the event of coolant loss, the cool­
ing system should be inspected immediately
by your authorized Audi dealer.
It is not
enough merely to add coolant.
In a
sealed system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheating.
A WARNING
The cooling system is under pressure and
can get very hot. Reduce the risk of scald­
ing from hot coolant by following these
steps.
- Turn
off the engine and allow it to cool
down.
- Protect your face, hands and arms from escaping fluid and steam by covering the
cap with a large, thick rag .
- Turn the cap slowly and very carefully in
a counter-clockwise direction while ap­
plying light, downward pressure on the
top of the cap .
- To avoid being burned, do not spill anti­
freeze or coolant on the exhaust system
Checking and filling 219
or hot engine parts. Under certain condi­
tions, the ethylene glycol in engine cool­
ant can catch fire.
([) Note
Do not add any type of radiator leak seal­
ant to your vehicle's engine coolant. Add- ing radiator repair fluid may adversely af­
fect the function and performance of your
cooling system and could result in damage
not covered by your New Vehicle limited
Warranty .
Adding coolant
Be very careful when adding engine coolant.
Before you check anything in the engine com­
partment ,
always read and heed all WARN­
INGS <=>
A in Working in the engine compart­
ment on page 212 .
Requirement: There must be a residual
amount of coolant in the expansion tank <=>(D.
.,. Turn
off the engine.
.,. Let the engine cool down.
.,. Place a thick rag over the coolant expansion
tank
<=> page 218, fig . 185 and carefully turn
the cap counter-clockwise
<=> .&_ .
.,. Add coolant mixed in the correct ratio
<=> page 218, Coolant up to the MAX mark­
ing.
.,. Make sure that the fluid level remains sta-
ble. Add more coolant if necessary.
.,. Twist the cap on again
tightly.
Replacement engine coolant must conform to
exact specifications <=>
page 218, Coolant.
We recommend using only coolant additive
G12 ++, G13 or in an emergency G12 +. Do
not
use a different additive. In an emergency use
plain water until you can get the correct addi­
tive and can restore the correct ratio. This
should be done as soon as possible.
If you have lost a considerable amount of
coolant , then you should add cold antifreeze
and cold water only when the engine is cold.
Always use
new engine coolant when refilling . .,.
•
•

220 Check ing and filling
Do not fill coolant above the "MAX" mark. Ex­
cess coolant will be forced out through the pressure re lief valve in the cap when the en ­
g ine becomes hot.
A WARNING
- The coo ling system is under pressure and
can get very hot. Reduce the risk of
scalding from hot coolant by following
these steps.
- Turn
off the engine and a llow it to cool
down.
- Protect your face, hands and arms from
escaping fluid and steam by covering
the cap with a large, thick rag.
- Turn the cap slowly and very carefully in a co unte r-clockwise d irection while
apply ing light, downward press ure on
the top of the cap.
- To avoid being burned, do not spi ll an­
tifreeze or coolant on the exhaust sys­
tem or hot engine parts. Under certa in
conditions, the ethylene glyco l in en­
g ine coolant can ca tch f ire.
- Antifreeze is poisonous. Always store an­
t ifreeze in its original container and we ll
o ut of the reac h of children.
- If you drain the coolant, it must be
caught and safely stored in a p roper con­
ta iner clear ly ma rked "poison".
(D Note
- Do not add coolant if the expansion tan k
i s empty. A ir could enter the cooling sys­
tem and damage the eng ine. If this is
the case, do not continue driving. Seek professional assistance.
- Coolant po llutes the e nv ironment and
could cause an engine fire. Excess coo l­
ant will be forced ou t through the pres ­
su re rel ief v alve in the ca p when the en­
gine becomes hot .
- If, in an emergen cy, only water can be
added, the correct ratio be twee n wa te r
and antifr eeze¢
page 218 must be re ­
stored as soon as possib le .
{® For the sake of the environment
D rained coo lant should not be reused . A l­
ways d ispose of used coolant whi le observ­
i ng a ll environmental regulations.
Radiator fan
The radiator fan switches on automatically by
itself
T he rad iator fan is driven by the engine v ia the
V-belt. The viscous clutch regulates the spee d
of the fan acco rding to the temperature of the
coolant.
An a uxiliary electric radiator fan* sw itches on
and
off depending on coolant temperature
and othe r vehicle ope rat ing condit ions .
A ft er yo u sw itch the eng ine
off, the aux iliary
f an can continue running for up to 10 m inutes
- even wit h the ignition
off. It can even switc h
on again later by itself¢.&. , if
- t he temper ature of the engine coo lant rises
due to the heat build -up from the engine in
the engine compa rtment, or
- the engine compa rtment heats up because
the vehicle is parked in intense sunlig ht.
A WARNING ~
- To reduce the risk of perso na l inj ury nev -
er touch the radiator fan.
- The a uxiliary electric fan is tempe rat ure
contro lled and can sw itch on sud denly
even when the engine is not running.
- The a uxiliary radiator fan switches on a u­
tomatically when the engine coo lant
reac hes a certa in temperature and will
continue to ru n until the coolant temper­
ature drops.

M N
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Brake fluid
Checking brake fluid level
The brake fluid level can be checked with a
quick glance.
N
N
;:;;
" 03
"'
Fi g. 186 Eng ine compartment: Cover on the brake flu ­
id reservoi r
Before you check anything in the engine com­
partment,
a lwa ys read and heed a ll W ARN­
ING S c:> .&.. in Working in the engine compart­
ment on page 212 .
~ Read the brake fluid level from the brake
fluid reservoir
c:> fig. 186, <=> page 214,
fig . 182.
The brake flu id level must be be­
tween the "MIN" and "MAX" markings.
The brake fluid reservoir is located at the rear
partition of the engine compartment on the
left side
<::;> page 214 .
The fluid level may drop slightly after some
time due to the automatic adjustment of the
brake pads . This is not cause for alarm .
If the brake fluid level falls
considerably be­
low the "MIN" mark, the brake warning/indi­
cator light (U.S. models:~, Canadian
models: .) will come on
r:> page 15. Do not
continue to operate the vehicle. The complete b rake system shou ld be thoroughly checked
by an authorized A udi dealer or qualified
workshop and the cause co rrected . If the
b rake fluid level is too low, the brake warn ing/
indicator light w ill illuminate. Contact an au­
thorized Audi dealer
immediately .
@ Tips
The brake f luid reservoir is located under­
neath the cover .
Checking and fillin g 221
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician.
Brake fluid absorbs moisture from the air. If
the water content in the brake fluid is too
high, corrosion in the brake system may result
after a period of time . The boiling point of the
brake flu id will also dec rease considerably and
decrease braking pe rformance.
Therefore, the brake fluid must be changed
every two years. Always use new brake flu id
which conforms to Federal Motor Vehicle
Standard "F MVSS 116 DOT 4".
The brake fluid reservo ir can be d iff icult to
reach, the refore, we recommend that you
have the brake fluid changed by your author­
i zed
Audi d ealer. Your dealer has t he correct
tools, the right brake fl uid and t he know-how
to do this for you .
A WARNING -.
-Brake fluid is poisonous . It must be stor­
ed only in the closed original container
out of the reach of children!
- Brake failure can resu lt from o ld or inap­
propriate brake f luid. Observe these pre­
cautions:
- Use only brake fluid that meets SAE
spe cificat ion
J 1 7 03 and conforms to
Federa l Moto r Ve hicl e Standard 116.
Always check with yo ur authorized Audi
dealer to make sure yo u are using the
correct bra ke fluid. The correct type of
brake f luid is also indicated on the
brake f luid reservoir.
- The brake fluid must be new. Heavy use
of the brakes can cause a vapor lock if
the brake fluid is left in the system too
l ong. This can seriously affect the effi­
c iency of the brakes as well as your
safety. Th is cou ld resu lt in an accident.
(D Note
Brake fluid will damage the paint of your
vehicle .

222 Check ing and filling
@ For the sake of the environment
Becau se of the pr oblem of proper disposa l
of brake flu id as we ll as the special tools
requ ired and the necessary expert ise, we
recommend that you have the brake fluid
changed by your author ized Audi dealer.
Battery
General information
Unde r normal operating conditions, the bat ­
tery in your Audi does not need any mainte ­
nance. With
high outside temperatures or
long daily dr ives we recommend that you have
the electro lyte level checked by an authorized
Aud i dea ler o r qualified workshop . The elec­
trolyte leve l sho uld a lso be checked each t ime
the battery is charged ¢
page 224.
Have the battery checked when you take your
ve hicle in for service . Yo u are well adv ised to
replace a bat tery that is older tha n 5 yea rs .
W ith certa in types of a irbag deployment, t he
battery is d isconnected from the vehicle elec­
tr ica l system fo r safety reasons ¢
& in Re­
pair, core and disposal of the airbags on
page 157.
Disconnecting the battery terminals
Some veh icle functions (power w indow regu­
lato rs, for example) are lost if the battery ter­
m inals a re discon nected. These functions have
to be re lea rned after the batte ry terminals a re
connec ted agai n. T o prevent this, the battery
should o nly be d isconnec ted from the vehicle
e lec trica l syste m when absolu tely necess ary
for repairs.
Vehicles not driven for long periods
I f yo u do not drive you r vehicle over a pe riod
of severa l days or weeks, elec trical co m po­
nen ts are gr adually cu t back o r swi tched off .
T his reduces energy consumption and main­
tains sta rting capab ility over a lon ger period
¢ page 191.
Some o f the conven ien ce f unct ions m ay no t
ope rate, su ch as the in ter ior lights o r the power seat adjus
tment. The convenience
funct ions wi ll be available again when yo u
tu rn on the ignition and sta rt t he engine.
Winter operation
Du ring the w inte r mon ths , b att ery capac ity
tends to dec rease as temperatures drop . This
is beca use more power is a lso consumed w hile
starting, and the headlights, rear win dow de­
f ogger, etc., are used more often.
Avoid unnecessa ry powe r consumpt ion, pa r­
ticu lar ly in ci ty traffic o r when traveling only
sho rt distances . Let yo ur autho rized A udi
dealer check the capacity of the vehicle bat ­
tery before w inter sets in ¢
page 224. A well
charged battery will not on ly prevent starting
problems when the weather is cold, but will
also last longer .
@ Tips
If your vehicle is left standing for seve ral
weeks at extremely low temperatures, the
vehicle battery s hou ld be removed and
s tored w her e it w ill not freeze. This will
preve nt i t fr om be ing d amaged and having
t o be repla ced .
Working on the battery
Be especially careful when working on or near
the battery.
The battery is located in the luggage compar t­
ment under the floor . Befo re you che ck any­
t hi ng in the luggage co mpartment,
read and
heed all WARNINGS
¢ .&, .
Always heed the safety warnings , when work­
i ng on the veh icle ba tte ry or the vehicle e le c­
t ric al sys tem to p reven t inju ry.
The following WARNINGS are very
important when working on the battery:
Always heed the following WARNING SYM ·
BOLS and safety precautions when working
on the battery .
®
Always wear eye protection .

224 Checking and filling
(D Note
- Do not disconnect the vehicle battery
when the ignition is switched on or when
the engine is running, otherwise, you will
damage e lectronic components i n the
electrical system.
- If your vehicle is going to stand for a
long period of time without being driven,
protect t he battery from "freezing", oth­
e rwise it w ill be damaged and w ill then
have t o be repla ced.
Battery charging
Starting the engine requires a well charged
batt ery.
Fig. 187 Eng ine compartment: Connectors for charger
a nd jumper cables
Always read and heed all WARNINGS below
c::> & and c::> & in Working on the battery on
page 223 .
•Turnoff th e ignit ion and all electrical con­
sumers.
• Make sure the area is well vent ilated when
yo u cha rge the battery .
• Ope n the engi ne hood
i=!.> page 2 12.
• Open the cove r o n the pos it ive pole
e!.>fig. 187.
• Connect the charger connectors according to
t h e instr uctions to the
jump start bolts.
(Bo lts under the cover = "positive", Bolts
with hex head= "negative").
• Only now plug the mains lead for the charg­
i ng equipment into the wall outlet and turn
i t on
c::> .&,. .
• Make sure the charging rate i s not over
30 amps /14.8 Volt .
• When the battery is fully cha rged: Turn the
charging equipment off and remove the
mains lead from the wall out let.
• Now remove the clamps for the charging
equ ipment.
.,. Close the cover on the positive pole .
.,. Close the hood
c::> page 212.
A discha rged battery can freeze at tempera­
tures of only 32 °F (0 °C). Allow a frozen bat­
tery to thaw comp letely before attempting to
charge i t
c::> .&.. However, we recommend not
u sing a thawed batte ry aga in because the ba t­
te ry casing can be c racked due to ic e f orma­
t io n an d can leak ba ttery a cid.
Battery charging (Maximum charging rate
of
30 amps/14.8 Volt)
When ch arg ing at low vo lta ges (e.g. wi th a
trickle charger ), the ba tte ry cables do not
have to be disconnected f irs t. T he bat tery
caps should
not be opened when charg ing a
battery .
It is no t necessa ry to remove the b att ery from
t h e luggage com partmen t.
Fast charging the battery (charging rate
above 14.8 Volts)
F or te chnica l re asons do not u se a batt ery
ch arger that uses voltage greater than
14 .8
Volts to c harge yo ur vehicle's battery.
A WARNING
.------
C harging a battery can be dan gero us.
-A lways follow t he operati ng inst ru ctions
p rovi ded by the battery charger manu ­
facturer when charg ing your battery.
- Never charge a frozen batte ry . I t may ex­
p lode because of gas trap ped in the ice.
A llow a frozen battery to thaw out f irst.
- Do not reuse batteries w hich were fro­
zen. The battery housing may have
cracked and weakened w hen the battery
froze .
- Charge the battery in a we ll ventilated
area. Keep away from o pen flame or elec­
tr ica l spark. Do not s moke. Hyd rogen gas
ge nera ted by t he battery is explos ive .