2014 AUDI A5 COUPE check engine

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-based coolant addi-
tive G13 antifreeze with anticorrosion 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 also raises the boil­
ing point of the coolant.
Do not reduce the concentration of the cool­
ant in the summer by adding plain water.
The
proportion of coolant additive must be at
least 50% but not more than 60%
to main­
tain antifreeze protection and cooling efficien­
cy. If the coolant frost protection is too low,
the coolant could freeze and damage the vehi­ cle heating and engine cooling system.
For year-round driving, antifreeze is added at
the factory for temperatures down to:
- -31°F(-35°C)USA
- -40 °F ( - 40 °C) Canada.
If you must add coolant, use a mixture of wa­
ter and coolant additive. Mixing the coolant
additive with distilled 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 206.
(D Note
- Before winter sets in, have the coolant
checked to see if the coolant additive in
Checking and filling 213
your vehicle is sufficient to meet the cli­
mate conditions. This is especially impor­
tant if you live in a region where the win­
ter is extremely cold. If necessary, in­
crease the proportion of coolant additive
to 60%.
- When adding coolant additive to your
cooling system, remember:
- We recommend using only coolant ad­
ditive G12++ or G13 for your vehicle.
This coolant additive is available at au­
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.
Adding radiator repair fluid may adverse­
ly affect the function and performance of
your cooling system and could result in
damage not covered by your New Vehicle
Limited Warranty.
Checking the engine coolant level
The engine coolant level can be checked with
a quick glance.
Fig. 164 Eng ine compartment: Cover on the coolant
expansion tank
"' Before you check anything in the engine
compartment,
always read and heed all
WARNINGS ¢ .&, in Working in the engine
compartment on page 206.
"'Park your vehicle on a level surface .
.,. Turn off the ignition.
.,. Read the engine coolant level from the cool­
ant expansion tank ¢
fig. 164, ¢ page 208,
fig. 161.
With a cold engine, the coolant Iii>

214 Check ing and filling
level should be between the "MIN" and
"MAX" markings. When the engine is warm,
the leve l may be slightly above the "MAX"
marking .
The location of the coolant expansion tank
can be seen in the engine compartment illus­
tration
c:> page 208.
To obtain an accurate reading, the engine must be switched
off.
The expansion tank in you r vehicle is equipped
with an e lectric coolant level sensor.
When the coolant level is too low, the warning light in the Auto-Check System
c:> page 17will
b link until you add coo lant and the level has
been restored to no rma l. Even though there is
an electric coolant level sensor, we still rec ­
ommend you check the coolant leve l from
time to time.
Coolant loss
Coolant loss may indicate a leak in t he cool ing
system. In the event of coolant loss, the cool ­
ing system should be inspected immediately
by your authorized A udi dealer.
It is not
enough merely to add coolant.
I n a
sea led system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheat ing.
A WARNING
The cooling system is unde r 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
dow n.
- Protect yo ur 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 wh ile ap­
plying light, downward pressure on the
top of the cap .
- To avoid be ing burned, do not spill ant i­
freeze or coolant on the exhaust system
'
or hot engine parts. Under certa in cond i­
tions, the ethylene glycol in engine coo l­
ant can catch fire.
(D Note
Do not a dd any type of radiator leak sea l­
ant to your veh icle's engine coolant. Add ­
i ng radiator repa ir fl uid may adverse ly af­
fect the funct ion and performance of your
cooling system and could result in damage
not covered by your New Veh icle L imited
War ranty .
Adding coolant
Be very careful when adding engine coolant.
Before you check anyth ing in the eng ine com­
partment,
always read and heed all WARN­
INGS c:> A in Working in the engine compart­
ment on page 206 .
Requirement: There m ust be a res idual
amount of coo lant in the expans ion tank
c:> (]) .
.,.. Turn off the eng ine .
.,.. Let the engin e cool down.
.,.. Place a thick rag over the coo lant expansion
tank
c:> page 213 , fig. 164 and carefully turn
the cap counter-clockwise
c:> .&_ .
.,.. Add coo lant m ixed in the correct rat io
c:> page 213, Coolant up to the MAX ma rk­
ing.
.,.. Mak e s ure t hat the fl uid leve l remains sta-
b le. Add more coo lant if necessary.
.,.. Twist the cap on again
tightly .
Replacement engine coo lant must confo rm to
ex act spec ific at ions
c:> page 213, Coolant.
We recommend using only coolant add it ive
G12 ++, G13 or i n an emergency G 12+. Do
not
use a different add it ive. In an emergen cy use
plain wa ter until yo u can ge t the correct addi­
tive and can restore t he correct ratio. This
sho uld be done as soon as possib le .
If you have los t a cons iderab le amount o f
coolant, the n you sho uld add cold ant ifree ze
and co ld wate r on ly when the engine is cold.
Always use
n ew engine coo la nt w hen refilling . .,.

Do not fill coolant above the "MAX" mark. Ex­
cess coolant will be forced out through the pressure relief valve in the cap when the en­
gine becomes hot .
_& WARNING
-The cooling 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 allow itto 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
applying light, downward pressure on
the top of the cap .
- To avoid being burned, do not spill an­
tifreeze or coolant on the exhaust sys­
tem or hot engine parts . Under certain
conditions, the ethylene glycol in en­
gine coolant can catch fire.
- Antifreeze is poisonous. Always store an­
tifreeze in its original container and well
out of the reach of children.
- If you drain the coolant, it must be
caught and safely stored in a proper con ­
tainer clearly marked "poison".
(D Note
- Do not add coolant if the expansion tank
is empty. Air could enter the cooling sys­
tem and damage the engine. If this is
the case, do not continue driving . Seek
professional assistance.
- Coolant pollutes the environment and
could cause an engine fire . Excess cool­
ant will be forced out through the pres­
sure relief valve in the cap when the en­
gine becomes hot.
- If, in an emergency, only water can be
added, the correct ratio between water
and antifreeze
¢ page 213 must be re­
stored as soon as possible.
Checking and filling 215
'
@) For the sake of the environment
Drained coolant should not be reused. Al­
ways dispose of used coolant while observ­
ing all environmental regulations.
Radiator fan
The radiator fan switches on automatically by
itself .
The radiator fan is driven by the engine via the
V-belt. The viscous clutch regulates the speed
of the fan according to the temperature of the coolant.
An auxiliary electric radiator fan* switches on
and
off depending on coolant temperature
and other vehicle operating conditions.
After you switch the engine
off, the auxiliary
fan can continue running for up to 10 minutes
- even with the ignition
off. It can even switch
on again later by itself ¢.&. , if
- the temperature of the engine coolant rises
du e to the h eat build-up from th e engin e in
the engine compartment, or
- the engine compartment heats up because
the vehicle is parked in intense sunlight.
_& WARNING ~
-To reduce the risk of personal injury nev-
er touch the radiator fan .
- The auxiliary electric fan is temperature
controlled and can switch on suddenly
even when the engine is not running.
- The auxiliary radiator fan switches on au­
tomatically when the engine coolant reaches a certain temperature and will
continue to run until the coolant temper­
ature drops. •
•

216 Checking and filling
Brake fluid
Checking brake fluid level
The brake fluid level can be checked with a
quick glance .
N N ~ N
" (X) (0
Fig. 165 Engine compartme nt: Cover on the brake flu ·
id reservo ir
Before you check anything in the engine com­
partment,
always read and heed all WARN·
INGS ¢ .&._ in Working in the engine compart­
ment on page 206 .
.. Read the brake fluid level from the brake
fluid reservoir ¢
fig. 165, ¢ page 208,
fig. 161.
The brake fluid 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 208 .
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 mod­
els: .) will come on¢
page 15. Do not con­
tinue to operate the vehicle . The complete
brake system should be thoroughly checked
by an authorized Audi dealer or qualified
workshop and the cause corrected.
If the
brake fluid level is too low, the brake warning/
indicator light will illuminate. Contact an au­
thorized Audi dealer
immediately .
@ Tips
The brake fluid reservoir is located under­
neath the cover.
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid absorbs moisture from the air. If
t he 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 fluid will also decrease considerably and
decrease braking performance.
Therefore, the brake fluid must be changed
every two years . Always use new brake fluid
which conforms to Federal Motor Vehicle
Standard "FMVSS 116 DOT 4".
The brake fluid reservoir can be difficult to reach, therefore, we recommend that you
have the brake fluid changed by your author­
ized
Audi dealer. Your dealer has the correct
tools, the right brake fluid and the 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 result from old or inap­
propriate brake fluid. Observe these pre­
cautions:
- Use only brake fluid that meets SAE
specification
J 1703 and conforms to
Federal Motor Vehicle Standard 116.
Always check with your authorized Audi
dealer to make sure you are using the
correct brake fluid. The correct type of
brake fluid is also indicated on the
brake fluid 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
long . This can seriously affect the effi­
ciency of the brakes as well as your
safety. This could result in an accident.
(D Note
Brake fluid will damage the paint of your
vehicle.

@ For the sake of the environment
Because of the pr oblem of proper d isposa 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
Under 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 dealer or qualified workshop . The elec­
trolyte leve l should also be checked each time
the battery is charged ¢
page 219.
Have the battery checked when you take your
ve hicle in for service . Yo u are well adv ised to
replace a battery that is older than 5 yea rs .
W ith certa in types of a irbag deployment, t he
b attery is d isconnected from the vehicle elec­
tr ica l system for safety reasons¢.&.
in Re ­
pair, care and disposal of the airbags on
page 150.
Disconnecting the battery terminals
Some vehicle functions (power w indow regu­
lators , for example) are lost if the battery ter­
m inals a re d isconnected. These func tions have
to be re lea rned after the batte ry term inals a re
connected agai n. T o prevent this , the bat tery
should only be d isconnec ted from the vehicle
e lec tric al system when absolu tely necessa ry
for repairs .
Vehicles not driven for long periods
If you do not drive you r vehicle over a period
of severa l days or weeks, elec trical compo­
nen ts are gr adually cut b ack o r swi tched off .
This redu ces energy cons umption and main­
tains starting capab ility over a longer per io d
¢ page 186.
Some o f the conven ience f unctions m ay not
ope rate, su ch as the in ter ior lig hts or t he
Checkin g and fillin g 217
power seat adjus tment. The convenience
funct io ns w ill be available again when yo u
turn o n the ign ition and start the engine.
Winter operation
D ur ing the w inte r mon ths, bat tery capa city
tends to dec rease as tempera tures drop . This
is beca use more power is a lso consumed wh ile
starting, and the headlights, rear window de­
fogge r, etc., are used more often.
Avoid unnecessary powe r consumpt ion, pa r­
ticular ly in city traffic or when traveling only
sho rt distances. Let yo ur authorized A udi
dealer check the capacity of the vehicle bat ­
tery before w inter sets in
¢ page 219. A well
charged battery will no t on ly prevent star tin g
problems w hen the weather is cold, but w ill
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
stored where it will not freeze . This will
p revent it from be ing damaged and having
to be repla ced .
Working on the battery
Be especially careful when working on or near
the bat tery.
The battery is located in the luggage compar t­
ment under the floor . B efo re you che ck any­
thi ng in the luggage compartment,
read and
heed all WARNINGS
¢ ,&. .
Always heed the safety warnings , when work­
i ng on the veh icle batte ry or t he vehicle e lec­
t rical 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· BO LS and safety precautions when working
on the battery .
®
Always wear eye protection.
•
•

218 Check ing and filling
&
Batter y acid contain s sulfuric acid . Al ·
wa ys wear glo ves and eye prote ction .
@
No
- spar ks
- flames
- smoking .
~
When a b attery i s ch arged , it p roduce s
h y d rogen ga s whi ch i s ex plosi ve and
c ould cau se per sonal inju ry.
®
Alwa ys keep the battery well out of
r ea ch of children .
A WARNING
Whenever working on the battery or on
the electrical system, there is the risk of
injury , acc ident and even fire. Read and
heed the following WARNINGS:
-Always wear eye protection. Do not let battery acid or any lead part icles get on
your sk in or cloth ing . Sh ield your eyes .
Explosive gases can cause blindness or
other injury .
- Battery acid contains sulfur ic acid . Sulfu­
ric acid can cause blindness and severe
burns.
- Always wear gloves and eye protection.
Do not tilt the battery because ac id
could leak out of the vent ilation open­
ings.
- If you get battery acid in yo ur eyes or
on your sk in, immediately rinse with
cold water for severa l minutes and get
medical attention .
- 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 neg -
ative cab les.
- When working on the battery, be sure
not to short-circuit the terminals with
tools or other metal objects. This would
cause the battery to heat up very quickly,
wh ich could lead to damage or explosion
and personal in jury.
-
- When a battery is charged, it produces
hydrogen 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 negat ive ground ca­
ble.
- Before performing any work on the e lec­
trica l system, switch off the engine and
ignit ion as well as any electrical equip­
ment. The negative cable on the battery
m ust be disconnected .
If you are just go­
ing to replace a light bulb, then it is
e nough to swi tc h off the lights.
- Before disconnecting the battery, switch
off the anti-theft alarm system! Other­
wise you wi ll set off the alarm.
- When disconnecting the battery, f irst
d isconnect the negat ive cab le and then
the posit ive c ab le.
- Before reconnecting the batte ry, ma ke
sure all e lectr ica l consumers are sw itch­
ed off . Re conne ct the pos it ive cab le first
and then the negative cable. Never inter ­
change the cables - this could start a fire!
- Never cha rge a frozen or a thawed-out
battery. It could exp lode! If a battery has
frozen, then it must be replaced . A dis­
charged battery can freeze over at 32°F
(QOC).
- Make sure the vent hose is always attach­
ed to the opening on the s ide of the bat­
tery.
- Never use batteries which are damaged.
There is the danger of an explosion! Al­
ways rep lace a damaged battery.
A WARNING
Ca lifornia Proposition 65 Warning:
- Battery posts, terminals and related ac­
cessories conta in lead and lead com­
pounds, chem icals known to the State of
California to cause cancer and reproduc­
tive problems . Wash hands after han-
dling.
~

(D Note
-Do not disconnect the ve hicle battery
when the ignition is sw itched on or when
the engine is running, otherwise, yo u will
damage e lectronic components in the
electrica l system .
- If your vehicle is going to stand for a
l ong period of time without being driven,
protect the battery from "freezing", oth­
erwise it w ill be damaged and w ill then
have to be replaced .
Battery charging
Starting the engine requires a well charged
batt ery.
F ig. 166 Engin e comp artm ent: Conn ecto rs for char ger
an d jumper cables
Always read and heed all WARNINGS below
c::, &. and c::, &. in Working on the battery on
page 218 .
.,. Turn off t he ignit io n and all electrical con­
s umer s .
.,. Make sure the area is well vent ilated when
you charge the bat tery .
.,. Open the engi ne hood
c::, page 2 06.
.,. Open the cove r on the pos it ive pole
¢ fig . 166 .
.,. Co nnect the charger connectors according to
the instructions to the
jump start bolts.
(Bolts under t he cover= "positive", Bolts
with hex head = "negative").
.,. Only now plug the mains lead for the charg­
i ng equipment into the wall outlet a nd turn
i t on
c::, &_ .
.,. Make sure the charging rate i s not over
30 amp s/14 .8 Volt .
Checkin g and fillin g 219
.,. When the bat tery is fully cha rged : Tu rn the
charging equ ipment off and
remove the
mains lead from the wa ll out let .
.,. Now remove the clamps for the charging
equ ipment.
.,. Close the cover on the positive pole .
.,. Close the hood
c::, pag e 206 .
A discha rged bat tery can freeze at tempera­
tures of only 32 °F (0 °C) . Allow a frozen bat­
tery to thaw comp letely before attempting to
cha rge it
c::, .&. . However, we r ecommend not
u sing a thawed batte ry aga in beca use the b at­
te ry casing can be cr acked due to i ce fo rma­
tion an d ca n leak b attery a cid.
Battery charging (Maximum charging rate
of 30 amps/14.8 Volt )
When charging at low vo ltages (e.g. wi th a
trickle charger) , the ba tte ry cables do no t
have to be disco nne cte d fir st. T he bat tery
caps should
not be opened when charg ing a
batte ry .
It is no t necessa ry to remove the b attery from
the luggage compartmen t.
Fast charging the battery (charging rate
above 14 .8 Volts)
Fo r tec hni cal re asons do not use a bat tery
c h arger th at uses voltage g reater than
1 4 .8
Volts to c harge yo ur veh icle's battery.
A WARNING
C harging a battery can be dangero us.
-A lways follow t he operati ng instr uctions
provided by the battery charger manu ­
facturer when charging your battery .
- Never cha rge a fro zen battery. It may ex ­
p lode because of gas trapped in the ice .
A llow a frozen battery to thaw out f irst.
- Do not reuse batteries wh ic h were fro­
zen. The battery housing may have
cracked and weakened w hen the battery
froze.
- Charge the battery in a well venti lated
area . Keep away from open flame or elec­
trical spark. Do not smoke . Hydrogen gas
generated by t he battery is explos ive . ..,

220 Check ing and filling
- To r educe the danger of explosion, never
co nnect or disconn ect cha rger cables
wh ile the c harger is operating.
- Fast char ging a battery is dangerous and
shou ld on ly be attempted by a compe­
tent technician w ith the proper equip­
ment .
- Battery acid that may spill d uring charg­
ing should be washed
off with a solution
of warm water and baking soda to neu ­
tralize the acid.
(Q) Note
Never use a fast charger as a booster to
start the engine . This will seriously dam­
age sensitive electronic components, such
as control units, relays, rad io, etc., as we ll
as the battery charger.
Battery replacement
The new battery must have the same specif/·
cations and dimensions as the original equip­
ment battery.
In tell igent energy management in your veh i­
cle is respons ible for d istributing the e lectr i­
cal energy throughout you r vehicle
~ page 186. The intell igen t energy m anage­
men t system w ill keep the engine ba tte ry
charged better then vehicles w ithout this sys­
tem . To make sure the additional e lectrica l en­
ergy is available once again after you have
changed the battery, we recommend that you install batteries o f the same type and ma nu­
facture only (the same as those installed at
the time your vehicle was delivered). Specifi­
cations are listed on the battery hous ing. You r
author ized Audi dealer must code the battery
in the ene rgy managemen t system to enable
you to use the ene rgy management functions
correctly after replac ing the battery.
I f it is not poss ible to use a battery of this
type, the new bat tery m ust h ave the s ame ca­
pac ity, voltage ( 12-volts), amperage, con ­
struction and plug sea ling. When installing the battery, make su
re the ig ­
nition and a ll electrical consumers are turned
off.
(D Note
Make sure the ventilat ion hose on the side
of the battery is connected, otherwise
fumes or battery acid can leak out .
@ For the sake of the environment
Because o f the p rob lem of p roper disposal
of a battery, we recommend your author ­
i zed Audi dealer change the battery fo r
you. Batteries contain sulfur ic acid and
l ead and must always be disposed of prop­
erly in comp liance with all environmental
regula tions. Dispos ing of veh icle batter ies
i mprope rly is very dange rous to the envi­
r o nment .
Windshield/headlight*
washer container
Fig. 167 En gin e compa rt m en t: Cove r on the w ind·
s h iel d a nd h eadligh t• was he r fl uid conta in er
.., N
-~ (X) a,
The washer fluid conta iner is marked w ith the
symbol
O on its cap~ fig. 167, ~ page 208,
fig .161.
.. Before yo u check any thing in the engine
compa rtment,
always read and heed all
WARNINGS q A in Working in the engine
compartment on page 206 .
.. Lift the fi ller cap tongue to add washer flu­
id. You can f ill the container to the top.
.. Press the cap back onto the filler neck after
fi lling the conta iner .
You can find the reservo ir
capacity in the table
in
q page 262. .,.