2015 AUDI A5 check engine

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-To avoid being burned, do not spi ll anti­
freeze or coolant on the exhaust system or hot engine parts. Under certain condi­
tions, the ethylene glycol in engine cool­ ant can catch fire.
- Antifreeze is poisonous. Always store anti­
freeze in its original conta iner and well out
of the reach of ch ildren .
-If you drain the coolant, it must be caught
and safely stored in a proper container
clearly marked "poison" .
(D Note
-Do not add coolant if the expansion tank is
empty . Air could enter the cooling system
and damage the eng ine .
If this is the case,
do not continue driving. Seek profess ional
ass istance.
- Coolant pollutes the env ironment and could
cause an eng ine fire . Excess coolant will be
fo rced out through the pressure relief valve
i n the cap when the eng ine becomes hot.
- If, i n an emergency , only water can be add­
ed, the correct ratio between wa ter and an­
tifreeze
i::;, page 196 must be restored as
soon as possib le .
@) For the sake of the environment
Drained coolant should not be reused. Always
dispose o f used coolant while observ ing all
environmental regulations .
Radiator fan
The radiator fan switches on automatically by it­
self.
The radiator fan is driven by the engine via the V­
be lt . The viscous clu tch regulates the speed of
the fan ac cording to the temperature of the cool ­
ant.
An auxiliary e lectr ic rad iator fan* switches on and
off depend ing on coolant temperat ure and othe r
veh icle operati ng conditions.
Afte r you switch the engine off, the auxiliary fan
can continue runn ing for up to 10 minutes -even
Ch eck in g and Fillin g
with the ignition off . It can even sw itch on again
later by itself¢& , if
- the temperatu re of the engine coo lant rises due
to the heat build- up from the engine in the en­
gine compartment, or
- the engine compartment heats up because the
veh icle is parked in intense sun light .
A WARNING
-To reduce the risk of persona l injury never
touch the radiator fan .
- The auxiliary electric fan is temperature con­ trolled and can switch on suddenly even
when the engine is not running.
- The a uxiliary radiator fan sw itches on auto­
matica lly when the engine coolant reaches a
certain temperature and will continue to run
until the coolant temperature drops.
Brake fluid
Checking brake fluid level
The brake fluid level can be checked with a quick
glance .
Fig. 1 65 Engine compar tment : Cove r on the b rake fl uid
r e servoir
Before you check anyth ing in the engine compart ­
ment,
al way s read and h eed all WARNIN GS
¢ _.& in Working in the engine compartment on
page 191 .
.,. Read the brake fluid level from the b rake fluid
reservoir
¢ fig. 165, ¢page 193, fig . 161 . The
brake fluid level must be between the
"MIN "
and "MAX " markings.
19 9

Checking and F ill in g
The brake fluid reservoir is located at the rear
partition of the engine compartment on t he left
side
c!,> page 193.
The fl uid level may drop slightly after some time
due to the automatic adjustment of the brake
pads. This is not cause for alarm.
If the b ra ke fluid level fal ls considerably below
the "MIN" mark, the brake warn ing/indicator
light (U.S. models:
1111 , Canadian models: . )
will come on
c!,> page 15 . Do not contin ue to oper­
ate the vehicle . The complete brake system
should be thoroughly checked by an author iz ed
Aud i dealer or qualified workshop and the cause
corrected . If the brake fluid level is too low, the
brake warning/ind icator light w ill illuminate .
Contact an authorized Audi dealer
i mmed iately .
{D) Tips
The brake fluid reservoir is located under­
neath the cove r.
Changing brake fluid
Have the brake fluid changed by an experienced
technician .
Brake fluid absorbs moist ure from the a ir. If the
water content in the brake fluid is too high, cor­ rosion in the brake system may result after a peri­
od of time . The boiling point of the brake flu id
w ill also decrease conside rably and dec rease
b rak ing perfo rmance.
Therefore, the brake flu id must be changed
e ve ry
two year s.
Always use new brake fluid w hich con­
forms to Fede ral Motor Vehicle Standard "FMVSS
1 16 DOT 4".
The brake fluid rese rvoir can be difficult to reach,
therefo re , we recommend that you have the
b rake fluid changed by your author ized
Audi
dealer .
Your dealer has the correct too ls , the
right brake fluid and the know-how to do t his for
you.
A WARNING
- B rake fluid is poisonous. It must be stored
on ly in the closed original container out of
the reach of children!
200
- Brake fail ure can resu lt from o ld or inappro­
priate brake fluid. Observe these precau ­
tions:
- Use only b rake fluid that meets SAE spec i­
f ica tion
J 170 3 and conform s to Federa l
Motor Vehicle Standard 116. Always check
with yo ur autho rized Audi dea le r to make
su re you are using the correct brake fl uid.
The correct type of brake flu id is also ind i­
cated on the brake fluid reservoir.
- The brake fl uid must be new. Heavy use of
the brakes can cause a vapor lock if the
brake f luid is left in the system too long.
This can seriously affect the efficiency of
the brakes as well as your safety. This
could result in an acc ident.
(D Note
Brake fluid will damage the paint of your vehi­
cle.
@ For the sake of the env ironment
Because of the prob lem of prope r disposal of
brake fluid as well as the special tools re­
qu ired and the necessary expert ise, we rec­
omme nd that you have the brake flu id
changed by you r autho rized Aud i dea le r.
Battery
, General information
U nder normal operating conditions, the battery
i n your Audi does not need any maintenance.
Wi th
high outside temperatures or long daily
drives we recommend that you have the e lectro ­
lyte level checked by an a uth orized Aud i deale r o r
qualified workshop . The electrolyte leve l should
a lso be checked each time the batte ry is c ha rged
c:!,> page 202.
Have the battery checked when yo u take your ve­
hicle in for service . You a re well adv ised to re­
pla ce a battery that is older tha n 5 years.
With certain types of airbag deployment, the bat ­
te ry is disconnected from the veh icle elect rical
system for safety reasons
c:!,> & in Repair, care
and disposal of the airbags on page 1 42.

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Disconnecting the battery terminals
Some vehicle functions (power window regula­
tors , for example) are lost if the battery termi­
nals are disconnected. These functions have to be
re learned after th e battery terminals are con­
nected again. To prevent this, the batte ry should
only be disconnected from the ve hicle electrical
system when absolutely necessary for repairs.
Vehicles not driven for long periods
If you do not drive your vehicle over a period of
several days or weeks, e lectrica l components are
gradually cut back or switched off. This reduces
energy consumption and maintains starting ca­ pability over a longer period
c:> page 175 .
Some of the conven ience functions may not oper­
ate, such as the interior lights or the power seat
adjustment. The convenience functions will be
available aga in when you turn 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 while s tart ing, and
the headlights, rear window defogger, etc ., are
used more often .
Avoid unnecessary power consumption, part icu­
larly in city traffic or when traveling only short
d istances . Let your authorized Aud i dealer check
the capacity of the vehicle battery before w inter
sets in ¢
page 202 . A well charged battery will
not only prevent starting problems when the
weather is cold, but will also last longer.
(D Tips
If your vehicle is left standing for severa l
weeks at extremely low temperatures, the ve­
hicle battery should be removed and stored
where it will not freeze. This will prevent it
from being damaged and having to be re­ placed.
Checking and Filling
Working on the battery
Be especially careful when working on or near
the battery.
The battery is located in the luggage compart­
men t under the floor. Before you check anything
in the luggage compartment ,
read and heed all
WARNINGS
c:> .&_ .
Always heed the safety warnings, when working
on the vehicle battery or the vehicle electr ical
system to prevent injury .
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.
A
Battery acid contains sulfuric acid. Al-
ways wear gloves and eye protection.
@
No
- sparks
- flames
- smoking.
~
When a battery is charged, it produces
hydrogen gas which is explosive and
could cause personal injury.
®
Always keep the battery well out of reach
of children.
A WARNING
= -
Whenever working on the battery or on the
e lectr ical system, there is the risk of injury,
accident and even f ire. Read and heed the fol ­
lowing WARNINGS:
- Always wear eye protection . Do not let bat­
tery ac id or any lead particles get on your
skin or clothing. Shield your eyes. Exp losive
gases can cause blindness or other in jury.
- Battery acid conta ins sulfuric acid . Sulfuric
acid can cause blindness and severe burns.
- Always wear g loves and eye protection. Do
not tilt the battery because acid could leak
out of the ventilation openings. ...,
201

Checking and Filling
-If you get battery acid in your eyes or on
your skin, immediately rinse with cold wa­
ter for several minutes and get medical at­
tention .
- If you should ingest any battery acid, seek
medical attention immediately .
- Do not expose the battery to an open flame, electric sparks or an open light .
- Do not smoke .
- Do not interchange the positive and nega-
tive cables.
- When working on the battery , be sure not to
short-circuit the terminals with tools or oth­
er metal objects . This would cause the bat­
tery to heat up very quickly, which could lead to damage or explosion and personal
injury .
- When a battery is charged, it produces hy­
drogen gas which is explosive and could
cause personal injury.
- Always keep the battery well out of the
reach of children .
- Before work is done on the electrical sys­
tem, disconnect the negative ground cable .
- Before performing any work on the electri­ cal system, switch off the engine and igni­
tion as well as any electrical equipment. The negative cable on the battery must be dis­
connected. If you are just going to replace a
light bulb, then it is enough to switch off
the lights.
- Before disconnecting the battery, switch off
the anti-theft alarm system! Otherwise you
will set off the alarm.
- When disconnecting the battery, first dis­
connect the negative cable and then the
positive cable.
- Before reconnecting the battery, make sure
all electrical consumers are switched off. Re­
connect the positive cable first and then the
negative cable. Never interchange the ca­
bles -this could start a fire!
- Never charge a frozen or a thawed-out bat­
tery. It could explode! If a battery has fro ·
zen, then it must be replaced. A discharged
battery can freeze over at 32°F (0°C).
- Make sure the vent hose is always attached
to the opening on the side of the battery .
202
-Never use batteries which are damaged.
There is the danger of an explosion! Always
replace a damaged battery.
A WARNING
California Proposition 65 Warning:
- Battery posts, terminals and related acces­
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive problems .
Wash hands after handling .
(D Note
- Do not disconnect the vehicle battery when
the ignition is switched on or when the en­
gine is running, otherwise, you will damage
electronic components in the electrical sys­
tem .
-If your vehicle is going to stand for a long
period of time without being driven, protect
the battery from "freezing", otherwise it
will be damaged and will then have to be re­
placed .
Battery charging
Starting the engine requires a well charged bat­
tery.
Fig. 166 E n g in e compar tmen t: C on nectors fo r charger and
jump er cables
Always read and heed all WARNINGS below
9 A and ¢ A in Working on the battery on
page 201.
.,. Turn off the ignition and all electrical consum­
ers.
.,. Make sure the area is well ventilated when you
charge the battery.
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~ Open the engine hood¢ page 191 .
~ Open the cover on the positive pole ~ fig. 166.
~ Connect the charger connectors accord ing to
the instructions to the
jump sta rt bolts . (Bolts
under the cover= "posit ive", Bo lt s with hex
head = "negat ive") .
~ Only now plug the ma ins lead for the charg ing
equipment into the wall outlet and turn it o n
~& -
~ Mak e sure the charging rate i s not o ver
30 amp s/14 .8 Volt .
~ When the battery is fully charged: Turn the
charging equipment
off and remov e the mains
l ead from the wall outlet.
~ Now remove the clamps for the charging equip-
ment.
~ Close the cover on the posit ive pole .
~ Close the hood 9 page 191.
A discharged battery can freeze at temperatures
of only 32 °F (0 °C). Allow a frozen battery to
thaw comp letely before attempting to charge it
9 & . However, we recommend not using a
thawed batte ry agai n because the batte ry casing
can be cracked due to ice forma tion a nd ca n leak
battery a cid.
Battery charging (Maximum charging rate of
30 amps /14.8 Volt )
When charging at low voltages (e.g. w ith a trickle
c harger ),
the battery cab les do not have to be
d isconnected first. The batte ry caps sho uld
not
be opened when charging a battery.
It is not necess ary to remove the ba tte ry from
t he luggage compa rtment.
Fast charging the battery (charging rate
above 14.8 Volts)
F or technica l reasons do no t use a ba ttery charg­
e r that uses voltage grea ter than 14.8 Vol ts to
charge your vehicle's battery .
A WARNING
Charging a battery can be dangerous.
- Always fo llow the operating instructions
provide d by the batte ry charge r manufactur ­
er when c harging your battery.
Checking and Fillin g
-Never charge a frozen battery. It may ex­
plode because of gas trapped in the ice . Al­
low a frozen battery to thaw out first.
- Do not reuse batteries wh ich were frozen.
The battery housing may have cracked and
weakened whe n the battery froze.
- Charge the battery in a well ventilated area.
K eep away from open flame or electrical
spark. Do not smoke. Hydrogen gas gene rat­
ed by the ba tte ry is explosiv e.
- To reduce the danger of explosion, never
connect or d iscon nect charger cab les wh ile
the charge r is operating.
- Fast cha rging a batte ry is dange rous and
should only be at tempted by a compe tent
technicia n w it h the proper eq uipment.
- Battery acid that may sp ill dur ing cha rging
should be washed
off with a solut io n of
warm water and baking soda to neutralize the a cid .
@ Note
Neve r use a fast charger as a booster to start
the e ng ine . T his w ill ser iously damage sensi­
tive elec tronic components, s uch as co ntrol
units , relays, radio, etc. , as we ll as the battery
cha rger.
Battery replacement
The new battery must have the same specifica­
tions and dimensions as the original equipmen t
battery.
Intelligent energy management in your vehicle is
r esponsible for distributi ng the elect rical energy
t hr ough out your veh icle
9 page 175. T he intelli ­
gen t energy management sys tem w ill keep the
engi ne battery cha rged better then vehicles with ­
out this system . To make s ure t he addit iona l elec­
trical energy is avai lab le once again after yo u
have changed the battery, we recommend that
you install bat teries of the same type and manu­
facture on ly (the same as those installed at the
t ime you r vehicle was del ivered) . Specificat ions
are listed on the battery hous ing . You r autho r­
i z ed Audi dea ler m ust code t he battery in the en-
ergy ma nagement system to en able you to use .,,.
203

Checking and Fill in g
th e e nergy management functions correctly after
replacing the battery.
If i t is not poss ible to use a battery of this type,
the new battery must have the same capacity,
voltage (12-vo lts), amperage, construct ion and
p lug sealing.
When insta lling the battery, make sure the igni­
tion and all elec trical consumers are t urned off.
CD Note
Make sure the ventilation hose on the s ide of
t he batte ry is connected, otherwise fumes or
bat tery ac id can leak out.
@ For the sake of the environment
Because of the problem of proper d isposa l of
a battery, we recommend your author ized
Audi dea le r change the battery for yo u. Ba t­
teries contain su lfuric acid and lead and must
always be disposed of properly in compliance
w ith all environmenta l reg ulations. D isposing
of vehicle batteries improperly is very danger­
ous to the environment.
Windshield/headlight* washer container
Fig. 167 Engine co mpa rtment : Cove r on th e w in d shiel d
an d h ead ligh t• was her fl uid container
The washer fluid containe r is marked with the
symbol
O on its cap ¢ fig . 167 , ¢page 193 ,
fig . 161 .
.,. Before you check anyth ing in the eng ine com­
partment , alw ays re ad and he ed all WARN·
I NGS
¢ ,& in Working in the engine comport­
ment on page 191 .
204
.,. Lift the filler cap tongue to add washer fluid.
Yo u can fill the container to the top.
.,. Press the cap back onto the filler neck after fill-
ing the container .
You can find the reservoir ca p acit y in the table in
~ page 242.
Clean water should be used when filling up. If
possible, use soft water to prevent scaling on the
washer jets . Always add a g lass cleaner solution
(with frost protection in the winter) .
CD Note
Do not mix engine coolant antifreeze or any
other additives to fill up the windsh ield wash­
er reservoir.

Emerg enc y s it uat ion s
Emergency situations
General
T his c hapt er is inte nded fo r tra ined e merg ency
c rews a nd worki ng p ers onn el w ho h ave the nec­
e ssa ry tool s and equipm ent t o perf orm the se
op era tion s.
Starting by pushing or
towing
CD Note
Vehicl es with an automa tic tra nsmission
c annot be st arted by pushing or towing .
Starting with jumper
cables
If necessary, the engine con be started by con­
necting it to the battery of another vehicle .
If the engine should fail to start because of a d is­
charged or weak battery, the battery can be con­
nected to the battery of
another vehicle, us ing a
p air of j umpe r cables to start the engine.
Jump er c abl es
Use only jumper cab les of sufficiently largec ross
sec tion
to carry the starter current safely. Refer
to the manufacturer's specifications.
Use on ly jumper cables with
insulated term inal
clamps which are d istinctly mar ked:
plus (+ ) cabl e in most cases co lored re d
minu s(-) cable
in most cases colored black .
A WARNING
Batteries contain electricity, ac id, and gas.
Any of these can cause very ser ious or fatal in­
jury . Fo llow the inst ruct ions be low for safe
hand Ling of your veh icle's battery.
- Always shield your eyes and avoid leaning
over the battery whenever possible.
- A discharged battery can freeze at tempera­
tures just below 32 °F (0 °C). Before con­
nect ing a jumper cab le, you must thaw the
236
frozen battery completely, otherwise it
could explode.
- Do not allow battery acid to contact eyes or
skin. Flush any contacted area with water immed iately.
- Improper use of a booster battery to start a
veh icle may cause an explosion.
- Vehicle batteries generate explosive gases .
Keep sparks, flame and lighted cigarettes
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 al­
so have a 12-Volt rat ing . The capacity (Ah)
of the booster battery should not be lower
than that of the discharged battery. Use of batter ies of different voltage or substantial­
ly different "Ah" rating may cause an explo­
sion and personal injury .
- Never charge a frozen battery . Gas trapped
in the ice may cause an explosion .
- Never charge or use a battery that has been
frozen . The battery case may have be weak­
ened .
- Use of batter ies of different voltage or sub­
stantially d ifferent capacity (Ah) rating may
cause an explosion and injury. The capacity
(Ah) of the booster battery sho uld not be
lowe r than that of the discharged battery.
- Before you check anything in the engine
compartment, always read and heed a ll
WARNINGS
qpoge 191.
CD Note
-App lying a higher voltage booster battery
wi ll cause expensive damage to sensitive
elec tronic components, such as control
units, re lays, radio, etc.
- T here must be no electrical contact between
the vehicles as otherwise cu rrent cou ld al­
ready start to flow as soon as the positive
(+) termina ls are connected.
@ Tips
The discharged battery must be properly con-
nected to the vehicle's electrical system. .,.

Emergency situation s
-The ba ttery ce ll lockin g screws must be
t ightened securely .
- Before you check anyt hing in the engine
compartment, always read and heed all
WARNINGS
c> page 191.
(D Note
Improper hook -u p of jumper cables can r uin
the generator .
- A lways connect POS ITIV E(+ ) to POS ITIV E
( + ), and NEGATIVE( -) to NEGATIVE( -)
gro und post of the battery manager control
unit .
- Check that a ll screw plugs o n the batte ry
ce lls are screwed in firmly . If not, tighten
pl ugs prior to connect ing clamp on negat ive
battery te rminal.
- Please note that the procedure for connect­
i ng a jumper cable as desc ribed above ap ­
plies specifica lly to the case of yo ur vehicle
being jump started . W hen you a re g iving a
j u mp sta rt to another vehicl e, do
not co n­
ne ct the negative ( -) cab le to the negative
( -) t erminal o n the di scharged battery @
c> fig. 187. In stea d, secure ly co nn ect the
nega tive ( -) cab le to either a solid me tal
com ponent that is f irm ly bolted to the en ­
gine block o r to t he engine bloc k itself. I f
the battery that is being charged does not
vent to the outside , escap ing battery gas
could ignite and exp lode!
Towing with a tow truck
General hints
Y o ur Audi requires special handling for towing.
The fo llow ing information is to be used by com ­
mercia l tow truck operato rs who know how to op­
erate their eq uipment safe ly .
- Never tow your Audi, towing will cause dam­
age to the engine and transmiss ion.
- Never wrap the safety chains or winch cables
around the brake lines .
- To pre vent unnecessary damage, your Audi
must be transported with a flat bed truck.
238
- To load the vehicle on to the flat bed , use the
towing loop found in the vehicle tools and at·
tach to the front or rear anchorage
c> page 238 and c:>page 239.
A WARNING
A veh icle being towed is not safe f or passe n­
gers . Never a llow anyone to ride in a ve hicle
be ing towed, fo r any reason .
Front towing loop
Do not install the front towing loop until it is
needed .
Fig. 188 Fro nt b um per: remov ing t he cove r cap
Fig. 18 9 Front b umper: sc rew ing in t he tow ing loop
The towing loo p fits in to the threade d hole locat­
ed on the right side o f the front bum per and cov ­
e red by a small cover when not in use .
.,. Remove the tow ing loop fr om the vehicle tool­
ki t
c> page 225 .
... Press the cover i n by app lyi ng shor t strong
pressure to the bottom part to release it from
the bumper
¢ fig. 188.
... Sc rew the tow ing loop tightly into the th readed
hole as far as it will go
c> fig. 189 and tighten it
w it h the wheel w rench . ..,.