2015 AUDI A3 check engine light

218 Check ing and F illin g
• Add coolant mixed in the correct ratio
¢page 216 up to the upper marking.
• Make sure that the fluid level rema ins sta-
ble. Add more coolant if necessary.
• Clove the cap securely.
A coo lant loss suggests a leak. Immediately
drive your vehicle to an authorized repair fa­
cility and have the coolant system inspected.
If the coolant system is not leaking, a loss can
come from the coolant cooking through over­
heat ing and being pushed out of the coolant
system.
.8, WARNING
The cool ing system is under pressure and
can get very hot. Reduce the risk of scald­
ing from hot coolant by following these
steps .
- Do not open the coo lant expansion tank
cap with the engine hot . There is a risk of
burns.
- T urn 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.
- T urn the cap slowly and ve ry carefu lly in
a counter-clockwise direction wh ile ap­
plying light, downward pressure on the
top of the cap.
- To avoid being b urned, do not spill anti­
freeze or coo lant on the exhaust system
or hot eng ine parts. Under certain condi­
t ions, the ethylene g lycol in engine cool­
ant can catch fire.
- The coo lant add itive and the coolant can
be dange rous to your hea lth. For th is
reason, keep the coolant in the or ig inal
conta iner away from children. There is a
risk of poisoning.
- Whe n work ing in the engine compart­
ment, remembe r that the radiator fan
can swit ch on even if the ignition is
switched off, wh ic h increases the risk of
persona l inju ry .
(D Note
Do not add coo lant if the expansion tank is
empty. Air cou ld enter the cooling system
and damage the engine. If this is the case,
do not continue dr iving. See your author­
i zed Audi dealer or qualified repair fac ility .
Radiator fan
The radiator fan switches on automatically by
itself
An a uxiliary electric radiator fan switches on
and off depending on coolant temperature
and other vehicle operat ing condit ions.
After you switch the engine off, the auxi liary
fan can continue running for up to 10 m inutes
- even w ith the ignition off.
It can even switch
on again later by itself¢.&. , if
- the temperature of the engine coo lant rises
due to the heat build- up from the engine in
the engine compartment, or
- the engine compartment heats up because
the vehicle is parked in intense sunlight.
.8, WARNING ,-
- To reduce the risk of personal injury nev-
er touch the radiator fan.
- The a uxiliary electric fan is temperat ure
controlled and can sw itch on suddenly
even when the engine is not ru nning.
- The auxiliary radiator fan sw itches on a u­
tomatically when the engine coo lant
reaches a certain temperature and will
continue to run until the coolant temper­
ature drops.

Brake fluid
Checking brake fluid level
Fig . 153 Engine co mpa rtment: cove r on the b rake f lu id
reservo ir
B efore you check anything in the engi ne com­
partment,
alwa ys read and heed all WARN ·
INGS r:=:,page 210 .
~ Read the brak e fluid level from the brake
fluid reservo ir
r:=;, fig . 153, r:=:, page 212,
fig. 149 .
The brake f luid leve l mus t be be­
tween the "MIN" and "MAX " ma rkings.
The location of the brake flu id reservo ir can be
seen in the engi ne compa rtment illust ra ti on
¢ page 212 .
The fluid level may drop slightly after some
time due to the automatic adjustment of the b rake pads . Thi s is not cause for alarm.
If the brake fluid level falls
considerably be ­
low the "MIN" mark, the b rake wa rning/ind i­
cato r light . (U .S . models)/ . (Canadian
models) will come on
r:=;, page 18 . Do not con­
tinue to operate the vehicle. The comp lete
brake system should be thoroughly checked
by an authorized A udi dealer or other quali­
f ied fac ility and the ca use corrected . If the
br ake fluid level is too low, the brake warning/
indica tor light w ill illuminate. Contact an au·
thor ized Audi dealer
immediately .
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid abso rbs moist ure from the air. If
the water content in the brake fluid is too
Che cking and Fillin g 219
high, co rrosion in the brake system may resu lt
after a period of time . The boiling point of the
brake f lu id will also decrease conside rably and
decrease braking performance.
T herefore, the brake fluid must be changed
eve ry two year s. Always use new brake f luid
which conforms to Federal Motor Veh icle
Standard "FMVSS 116 DOT 4".
The brake fluid reservoi r can be difficu lt to
reach, therefore, we recomm end that you
have the brake fluid changed by your author­
i z ed
Audi dealer . Your dealer has the correct
tools, the right brake flu id and the know-how
to do this for you .
A WARNING
-
-Brake flu id is poisonous. It must be stor-
ed only in the closed or iginal containe r
out of the rea ch of children!
- Brake failure can resu lt from o ld or inap­
p rop riate brake f lu id. Observe these pre­
cautions:
- Use only brake f luid that meets SAE
spec ificat ion
J 1703 and conforms to
Federa l Motor Ve hicle Standard 116.
Always check with your authorized Audi
dealer to make sure yo u are using the
cor rect bra ke fluid. The cor rect type of
brake f luid is also i nd icated on t he
brake f lui d rese rvoir.
- The bra ke flu id must be new. Heavy us e
of the brake s can cause a vapo r lock if
the b ra ke fluid is left i n the system too
l ong . This can se riously affect the effi ­
ciency of the brakes as we ll as your
safety . This co uld resu lt i n an accident .
(D Note
Brak e fluid will dam age the pa int of your
vehicle .
@ For the sake of the environment
Because of the p rob lem of proper disposal
o f bra ke fluid as well as the spec ial too ls
r equired and the necessary exper tise, we
recommend that yo u have the brake flu id
changed by yo ur authorized Audi dea ler.

220 Checking and Filling
Battery
General information
Under normal operating conditions, the bat­
tery in your Audi does not need any mainte­
nance. With
high outs ide temperatu res or
long daily drives we recommend that you have
the electro lyte level checked by a service fa­
cility. The e lectrolyte level shou ld also be
checked each time the battery is charged
c:>page222.
Have the battery checked when you take your
vehicle in for service. You are well advised to replace a battery that is older than 5 years.
With certain types o f airbag deployment, the
battery is disconnected from the vehicle elec ­
trica l system for safety reasons
c;, .&. in Re­
pair , care and disposal of the airbags on
page 156.
Disconnecting the battery terminals
Some vehicle functions such as power win­
dows are unavai lable if the battery termina ls
are d isconnected. These functions have to be
relearned after the battery terminals are con­
nected again. To prevent this, the battery
should only be disconnected from the vehicle
electrical system when absolutely necessary
for repairs .
To reprogram the functions, proceed as fol­ lows:
Function Reprogramming
Power window one-c;, page 40, Correcting
touch up/down power window mal-
function functions
Remote control key If the vehicle does not
or react to the key, it
convenience key must be synchroni zed
c:>page 33
Digital clock c:>page 10
ESC indicator light The indicator light
goes out after driving
a few meters
Vehicles not driven for long periods
If you do not drive your vehicle over a period
of severa l days or weeks, e lectrica l compo­
nents are gradually sca led back or switched
off. This reduces energy consumption and
maintains starting capability over a longer pe­
riod
c;, page 190. Some of the conven ience
functions may not operate, such as the interi­
or lights or power seat adjustment. The con ­
venience functions will be availab le aga in
when you switch on the ignition and start the
engine.
Winter operation
During the winter months, battery capacity
tends to decrease as temperatures drop. This
is because more power is also consumed wh ile
sta rting, and the headlights, rear window de­
fogger, etc. , are used more often.
Avoid unnecessary power consumpt ion, par­
ticularly in city traffic or when traveling only
short distances. Let your authorized Aud i
dealer check the capacity of the vehicle bat­
tery before winter sets in ~ page 222. A well
charged battery will not on ly prevent starting
problems when the weather is cold, but will
also last longer.
A WARNING -
-Work on the battery requ ires expert
know ledge. Contact your authorized Audi
dealer qualified repair facility for infor­
mat ion regarding the vehicle battery.
There is a risk for chemical burns or ex­
p losions.
- Never open the vehicle batte ry . Do not
try to change the battery electrolyte lev­
el. Otherwise explosive gas will escape
from the battery and increase the risk of
an explosion .
(i) Tips
If your vehicle is left standing for several
weeks at extremely low temperatures, the
vehicle battery should be removed and
stored where it w ill not freeze. This will ..,.

prevent it from being damaged and having
to be replaced .
Working on the battery
Be especially careful when working on or near
the battery.
The battery is loca ted in the luggage compart­
men t under the floor. Before yo u check any­
thing in the l uggage compartment,
read and
hee d all WARNINGS
¢ _A .
Always heed the sa fe ty warning s, when work­
i ng on the vehicle battery or the vehi cle elec ­
trica l system to prevent injury.
The following WARNINGS are very
impo rtant when working on the battery:
Alway s heed th e following WARNING SYM-
BOLS and saf ety precaution s when working
o n the b att ery.
®
Always wear e ye protection.
A
Batter y ac id contains sulfu ric acid .
Always w ear glo ves and e ye p rote c-
t ion .
@
No
- spark s
- flames
- smo king.
~
Wh en a battery i s charge d, it produ -
ce s hy d rogen ga s whi ch i s ex plo siv e
and could cau se perso na l injur y.
®
Alway s keep the b atter y w ell o ut of
r e ach of childr en.
A WARNING
Whenever working on the bat tery or on
the electrical system, there is the risk of
injury, accident and even fire. Read and
heed the following WARNINGS :
- Always wear eye p rotection. Do not let
battery acid or any lead particles get on
yo ur sk in or clothing. Sh ield your eyes.
Explosive gases can cause blindness or
other injury.
-
Checking and Fillin g 221
-Battery acid contains sulfuric acid . Sulfu­
ric acid can cause blindness and severe
burns.
- Always wear g loves and eye protection.
Do no t tilt the ba ttery because acid
could leak out of the ventilat ion open­
ings .
- If you ge t bat tery acid in your eyes or
on your skin, immediately rinse with
cold water for several minutes and get
med ical attention .
- If you should ingest any batte ry acid,
seek medical attention immediately.
- Do not expose the ba tte ry to an open
f lame, e lectric sparks or an open light .
- Do not smoke.
- Do not in terchange t he positive and neg-
ative cables.
- When working on t he battery, be su re
not to short-cir cuit the termina ls w ith
too ls or othe r metal objects. This would
cause the battery to heat up very quickly,
which could lead to damage or explosion
and pe rsonal injury.
- When a battery is charged, it produces
hydrogen gas which is explosive and
could cause personal inju ry.
- Always keep the battery well out of the
reach of children.
- Before work is done on the elect rical sys ­
tem, disconnect the negative ground ca ­
ble.
- Before performing any work on the e lec­
trical system, switch off the engine and ignit ion as well as any electrical equip­
ment. The negative cable on the battery
must be disconnected. If you are just go­
ing to replace a light bulb, then it is
e nough to switc h off the lights.
- Before disconnecting the battery, switch off the anti-theft alarm system! Other­
wise you will set off the alarm.
- When disconnecting the battery, first
disconnect the negat ive cab le and then
the posit ive cab le.
- Before reconnecting the battery, ma ke
sure all e lectr ica l consumers are sw itch­
ed off. Reco nne ct the pos it ive cable first
•
•
•

Emergency situations
General
This chapter is intended for trained emer­
gency crews and working personnel who have the necessary tools and equipment to
perform these operations.
Starting by pushing or
towing
(D Note
Vehicles with an automatic transmission
cannot be started by pushing or towing.
Starting with jumper
cables
If necessary, the engine can be started by
connecting it to the battery of another vehi­
cle.
If the engine should fail to start because of a
discharged or weak battery, the battery can be
connected to the battery of
another vehicle,
using a
pair of jumper cables to start the en­
gine.
Jumper cables
Use only jumper cables of sufficiently large
cross section to carry the starter current safe­
ly. Refer to the manufacturer's specifications.
Use only jumper cables with
insulated termi­
nal clamps which are distinctly marked :
plus(+) cable in most cases colored red
minus(-) cable
in most cases colored black.
A WARNING
Batteries contain electricity, acid, and gas.
Any of these can cause very serious or fatal
injury. Follow the instructions below for
safe handling of your vehicle's battery.
- Always shield your eyes and avoid lean­
ing over the battery whenever possible.
- A discharged battery can freeze at tem­
peratures just below 32 °F (0 °C). Before
Emergency situations 259
connecting a jumper cable, you must
thaw the frozen battery completely, oth­
erwise it could explode.
- Do not allow battery acid to contact eyes
or skin. Flush any contacted area with
water immediately .
- Improper use of a booster battery to start a vehicle may cause an explosion.
- Vehicle batteries generate explosive gas­
es. Keep sparks, flame and lighted ciga­
rettes away from batteries.
- Do not try to jump start any vehicle with a low acid level in the battery.
- The voltage of the booster battery must
also have a 12-volt rating. The capacity
(Ah) of the booster battery should not be
lower than that of the discharged bat­
tery . Use of batteries of different voltage
or substantially different "Ah" rating
may cause an explosion and personal in­
JU ry.
- Never charge a frozen battery. Gas trap­
ped in the ice may cause an explosion.
-Never charge or use a battery that has
been frozen. The battery case may have
be weakened.
- Use of batteries of different voltage or
substantially different capacity (Ah) rat­
ing may cause an explosion and injury.
The capacity (Ah) of the booster battery
should not be lower than that of the dis­
charged battery.
- Before you check anything in the engine
compartment, always read and heed all
WARNINGS
¢ page 210.
(D Note
-Applying a higher voltage booster bat­
tery will cause expensive damage to sen­
sitive electronic components, such as
control units, relays, radio, etc.
- There must be no electrical contact be­
tween the vehicles as otherwise current
could already start to flow as soon as the
positive(+) terminals are connected. ..,. •
•
•

Consumption (fuel) ... ..... .. .. .. .. .. 2 7
Contact ing N HTSA .............. .... 129
Controls cleaning .......... .... .. .. . 203
Conven ience key
E mergency operation ... ... .. .. .. .. .. 75
I ndicator light . . . . . . . . . . . . . . . . . . . . . 7 5
Starting the engine (START ENGINE STOP button) .. .. ................. .. .... 73
Stopping the engine (START ENGINE
STOP bu tton) ............ .... .. .. .. 74
Sw itch ing the ign ition on ......... ... 73
un locking/locking ........... .... ... 34
Conven ience opening/closing .. .. .. .. .. 39
Conver tible c hild safety sea ts .. .. .. .. . 173
Convertible locking retractor
Activating . . . . . . . . . . . . . . . . . . . . . . . .
179
D eactivating ................ .. .... 180
Using to secure a c hild safety sea t
1.7 7, 179
Coolant
refer to Engine coo lant ..... ... ... .. 216
Coolant system
Adding coolant . ... .... ... .. .. .. .. .
2 17
Coolant leve l check ing ..... .. .. .. .. . 217
Eng ine coolant temperature gauge .. .. 12
Cooling mode (automatic clima te con trol
system) ..... .. ... .. ..... ... .. .. .... 66
Cooling mode (manua l cl imate control sys-
tem) ...... .. ................. .. .... 65
Cooling system Indicator lights . . . . . . . . . . . . . . . . . . . . 20
Cornering light .... ..... ... .. .. .. .. .. 42
C ruise control system
C hanging speed . . . . . . . . . . . . . . . . . . . . 80
D escr ipt ion . ............. .. .. .. .. ..
79
P rese lecting speed . . . . . . . . . . . . . . . . . . 80
Sw itching off .. .. ..... ... .. .. .. .. .. 80
switch ing on . ... .. .... ... .. .. .... .. 80
(upho lde rs . . . . . . . . . . . . . . . . . . . . . . . . . 5 7
Current consumpt io n . . . . . . . . . . . . .
26, 27
D
Data recorder . . . . . . . . . . . . . . . . . . . . . . 185
D ate display . ............. .... .. .... 10
Daytime running lights .......... ... ... 42
Inde x 275
Declarat ion of compliance
Adaptive cruise contro l .. .... ... .. ..
2 71
A udi s ide ass ist . ... . .. ... .... ... .. 2 7 1
Ce ll phone package ................ 271
Convenience key .. .... ............. 271
Electronic immob ilizer ............. . 271
Homelink universal remote con trol ... 271
Remote cont ro l key ............... . 271
Decorative parts/tr im cleaning .... .. .. 203
De fec tive light bu lb w arning
Ind icator light ..... . .. .. ..... ... .. . 2 4
Defrost ing (w indsh ie ld)
automat ic cl imate control system .. .. .
6 7
man ua l cl imate co ntrol system ... .. .. . 65
DEF (instrument clus ter) ......... .. .. .
11
Del uxe a utomatic climate control
refer to Climate contro l system (auto -
matic) .... .. .. .. ................. .
66
Determining co rrec t load l imit .... .. .. 234
D igital compass . . . . . . . . . . . . . . . . . . . . . 50
Dimensions ....... .. . .. .. ..... ... ..
266
D imming the rearv iew mi rror ..... .. .. . 49
D isplays cleaning .. ................. 203
D istance ... .. .. .. .. . .. ... .... ... .. .
27
Door/ rear lid warning . .. .. ...... .... .. 26
Door contact switch . . . . . . . . . . . . . . . . . . 45
Doors Child sa fety lo ck (mech ani cal) .... .. .. . 38
Driver informat io n system ........... ..
26
CD/rad io disp lay .. .. . .. .... .... .. .. . 26
Door/rear lid wa rni ng . ...... ... .... . 26
Drive r messages . . . . . . . . . . . . . . . . . . . . 14
E ff iciency program . . . . . . . . . . . . . . . . . . 28
Ind icator lights .... . .. .. ..... ... .. . 14
On-board computer .. .. ..... ... .. .. .
27
Outside temperature disp lay .. ... .. .. . 26
Serv ice interval display . . . . . . . . . . . . . . 13
U sing the mu ltifunction steering wheel .
26
Driver seating position ... ..... ... .. .. 122
D rive select
refer to Aud i d riv e select ........... . 102
D riving safely . . . . . . . . . . . . . . . . . . . . . .
121
Drivi ng throug h wate r ........... .. .. 194
Driving time . . . . . . . . . . . . . . . . . . . . . . . .
27
D ust filter
refer to Poll utant fi lter ......... .... . 64
•
•
•

276 Index
E
ECO mode (automatic climate control sys -
tem) . ..... .. ................ ..... .. 67
EDL
refer to Electronic differentia l lock . .. . 185
Efficiency program . . . . . . . . . . . . . . . . . . . 28
Description . ...... .......... ... .. .. 28
Fuel economy messages . . . . . . . . . . . . . 29
Other equipment . . . . . . . . . . . . . . . . . . . 29
Electrical accessories
refer to Socket ............. .. .... .. 56
Electromechanical parking brake
refer to Parking brake ............... 76
Electromechanical steering .. .. .. .. .. . 189
I ndicator lights .......... .. .. .... . 189
Electronic differential lock ... .... .... . 185
Indicator light . . . . . . . . . . . . . . . . . . . . . 22
Electronic immobilizer ....... ... .... .. 36
also refer to Immobilizer . . . . . . . . . . . . 31
E lect ronic interaxle differential lock .... 185
Electronic speed limiter ..... .. .. .. .. . . 30
Electronic stabilization control (ESC)
Indicator light . . . . . . . . . . . . . . . . . . . . . 22
Electronic Stabilization Control (ESC) ... 185
Emergency assistance .......... .... . 246
Emergency flasher .......... ... .... .. 43
Emergency flashers
I ndicator light . . . . . . . . . . . . . . . . . . . . . 25
Emergency operation Emergency braking function .. .. .. .. . . 78
Front passenger's door/rear doors . . . . . 3 7
L uggage compartment lid ........ .. . 246
Panorama sunroof ........ .. .. ...... 41
with conven ience key .... .. .. .. .. .. . . 75
Emergency release Fuel filler door .............. ... ... 209
Selector lever . . . . . . . . . . . . . . . . . . . . . 112
Emergency starting ........ .. .. .. .. . 259
Emergency towing ......... .. .. .. .. . 261
Energy management . . . . . . . . . . . . . . . . 190
Indicator light . . . . . . . . . . . . . . . . . . . . . 20
Engine Coolant .. .. ..................... . 216
Starting with jumper cables .... .... . 259
starting (button) . .. ...... .. .. .. .. . . 73 Starting (driver messages with conven-
ience key) ..... .. ................ .. 75
starting (key) . ... ................ .. 70
stopping (button) ............. ..... 74
stopping (key) ................ ..... 72
Engine compartment
Closing the hood . . . . . . . . . . . . . . . . . . 211
Opening the hood ................ . 211
Overview .. .... .. ... .......... .... 212
Safety precautions ............... .. 210
Engine control (indicator light) . . . . . . . . . 23
Engine coolant .. .. .......... ... .. .. 216
Radiator fan ... .. ... .......... .... 218
Engine oil .. ................... .... 212
adding . .. .. .. .. ... .......... .... 215
Changing . ...... ... ......... ... .. 216
Checking the oil level ... ..... ... .. .. 215
Dipstick... .. .. .. .... .... .... 212, 215
Indicator light .................... . 20
Oil consumpt ion .. ............. .. .. 214
Oil grades ..... .. ............. .... 212
Specification and viscosity ........ ... 212
Use ..... ..... .. .. .............. . 215
Engine speed limitation ( indicator light) . 23
Environment Break -in per iod . .. ... ....... ... .. .. 193
Catalytic converter ....... ...... .. .. 194
Disposing of your vehicle battery ..... 223
Driving at high speeds .......... .... 195
Driving to minimize pollution and noise 195
Fuel economy .... ................ . 195
Letting the vehicle stand and warm up . 196
Proper disposal of drained brake fluid . 219
Proper disposal of drained engine oil .. 216
Unleaded fuel .... ... .......... .... 206
What should I do with an old battery? . 223
EPC (engine control) ................ .. 23
ESC Electronic stabilization control ... .. .. 185
Post-coll is ion brake assist ..... .. .. .. 186
Sport mode ... .. ................ . 187
ESP
refer to ESC ... .. ..... ..... ... .. .. 185
Event Data Recorder (EDR) ............ 185
Exhaust tail pipes cleaning ........... 202
Exterior lighting ... ..... ..... ... .. .. . 42