2013 AUDI A7 check engine

Engine cooling system
Coolant
The engine coolant performs two functions: it
keeps the engine from overheating and it pro ­
te cts the engine from freezing in the winter .
The cooling system is sealed and generally re­
qu ires 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 water and the manufacturer's gly ­
col-based coolant additive G13 ant ifreeze
w ith anticorrosion add itives (50% fo r USA
models; 60% for Canad ian models). This mix­
ture bot h assu res the ne cessary frost protec­
tion and protects metal components in the
engine's coo ling system from corrosion and
scaling. It also raises the boili ng po int of t he
coolant.
D o not red uce the concentration o f the coo l­
ant in the summer by adding plain water .
The
proportion of coolant addit ive must be at
least 50% but not mo re than 60 %
to main­
tain antifree ze protection and cooling efficien­
cy. If the coolant frost protection is too low,
the coolant cou ld 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:
- -3 1°F (-35°C)USA
- -40 ° F ( - 4 0 °C) Canada.
A WARNING
Before yo u check anything in the engine
compartment , always read and heed a ll
WARNINGS
¢ & in Working in the engine
compartment on page 230.
(D Note
- Befo re winter sets i n, have the coolant
chec ked to see i f th e coo lant ad dit ive i n
you r vehicle is suffic ient to meet the cli­
mate cond itions . T hi s is especially impor­
ta nt if yo u live in a regi on whe re the w in-
-
Checkin g and fillin g 237
ter is ex treme ly co ld. If necessary, i n­
crease t he p ro po rtion of coo lant additive
to 60%.
- W hen a dding coolant additive to yo ur
cooling system , remembe r:
- We recommend us ing on ly coo la nt ad­
di tive G 12++ or G 13 (check the labe l)
fo r you r ve hicl e. This coolant additive is
a v ailabl e at author ized Aud i de alers.
Ot he r ty pes of antifree ze can signifi­
cantly reduce corros ion p rotec tion. The
r es ulting co rrosion can cause a loss of
coolant and serio us engine damage .
- Do not add any ty pe of rad iator leak seal ­
ant to you r vehicle's engine coo lant .
Add ing radiator repair flu id may adverse ­
ly affect t he fu nction and performance of
your cooling system and cou ld result in
damage not covered by yo ur New Ve hicle
L imited Warranty .
Checking the engine coolant level
The engine coolant level can be checked with
a quick glance.
Fig. 19 2 Engine co mpart ment: cover on t he coo la nt
expansio n ta nk
Before you check a nyth ing in the eng ine com­
partment,
always read and heed all WARN­
INGS <=>&.
in Working in the engine compart ­
ment on page 230 .
.,. Park yo ur vehicle on a level surface .
.,. Switch off the ignition .
.,. Read the e ngine coolant level from the
coo la nt expansion tan k<=>
fig . 192,
¢ fig. 189 . With a cold engine, the coolant
level s hou ld be be tween the "m in" and
" max" mar kings. Whe n the engi ne is w arm,
Ill>-

238 Checking and filling
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 232.
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 16 will
illuminate until you add coolant and the level
has been restored to normal. Even though
there is an electric coolant level sensor , we
still recommend 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.
_& 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
or hot engine parts. Under certain condi­
tions, the ethylene glycol in engine cool­
ant can catch fire .
(D 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 ¢&. in Working in the engine compart ­
ment on page 230.
.. Turn off the engine .
.. Let the engine cool down.
.. Place a thick rag over the coolant expansion
tank ¢
fig. 192 and carefully twist the cap
counter-clockwise ¢,&. .
.,. Add coolant.
.. Twist the cap on again
tightly.
Replacement engine coolant must conform to
exact specifications ¢
page 23 7, 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 additive
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.
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 coo lant by following
these steps.
- Turn
off the engi ne and a llow it to cool
down.
- Protect your face, hands and arms from
escapi ng fl uid and steam by cover ing
the cap with a large, thick rag .
- Turn the cap slowly and very ca refully
i n a cou nte r-clockw ise dir ect ion while
a pply ing lig ht, downwa rd p ress ure on
the top of the cap.
- To avo id being burned, do no t sp ill an­
tifree ze o r coolan t on t he exh aust sys­
tem or ho t engine parts . Un der certain
conditions, the ethylene glyco l in en­
gine coolant can catch fire .
- Antifree ze is poisono us. Always store an­
tifreeze in its or iginal co ntainer and we ll
o ut o f the reac h of children.
- If you drain the coolant , it must be
caught and safely stored in a p roper con ­
tainer clear ly marked "poison".
(D Note
- Coolant po llutes the env ironment and
could ca use a n engine fire . Excess coo l­
ant wi ll be forced out through the pres ­
sure re lief va lve 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 237 must be re­
stored as soon as possib le .
@ For the sake of the environment
Drained coolant should not be re used . Al­
ways dispose of used c oolant while observ­
ing all envir onmental regulations .
Radiator fan
The radiator fan switches on automa tically by
itself
An auxiliary e lectric radiator fa n switches on
and
off depending on coolant temperature
and other ve hicle operating conditions.
Checkin g and fillin g 239
After you switch the engine off, the auxi liary
fan can continue running for up to 10 minutes
- even w ith the ign ition off. It can even switch
o n again later by itself¢.& , if
- the temperature of the engine coo lant rises
due to the heat build- up from the engine in
the engi ne compartment, or
- the engine compa rtment heats up because
the vehicle is parked in intense sunlight.
&_ WARNING
--To reduce the risk of persona l in ju ry nev-
er touch the radiator fan .
- The a uxiliary electric fan is tempe rat ure
contro lled and can switch on suddenly
even when the engine is not ru nning.
- The a uxiliary radiator fan sw itches on a u­
tomatically when the engine coo lant
reaches a certai n temperature and will
cont inue to ru n until the coo lant temper­
atur e drops.
Brake fluid
Checking brake fluid level
N
N
N
.,; 0:, a,
Fig. 193 Engin e co mpa rt m ent: cove r on t he bra ke fluid
reservo ir
Before you check anything in the eng ine com­
partment,
alw ays r ead and heed all WARN­
INGS c:> A in Working in the engine compart­
ment on page 230 .
.. Read t he brake fluid level from the brake
fluid reservoir
c:> fig. 193, c:> fig. 189. The
brake fluid level must be between the "MIN"
and "MAX" markings. .,..

24 0 Ch eck ing and filling
The location of the brake fluid reservo ir can be
seen in the engine compartment illustration
¢ page 232.
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.
I f the brake fluid level falls
considerably be­
low the "MIN" mark, the brake warning/ind i­
cator light
1111 (U .S . models)/ . (Canadian
models) will come on¢
page 15. Do not con­
tinue to operate the vehicle. The comp lete
brake system shou ld be thoroughly checked
by an au thorized Audi dealer or other quali­
fied facility and the cause corrected . If the
brake fluid level is too low, the brake warn ing/
indicator light w ill illuminate . Contact an au­
thor ized Audi dealer
imm ediatel y.
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid absorbs moisture from the a ir . If
the water content in the brake fluid is too
h igh , corros ion in the brake system may result
after a per iod of t ime . The bo iling po int of the
brake fluid w ill also decrease considerably and
dec rease braking performance.
Therefore, the brake flu id must be changed
ev ery two year s. Always use new b rake fluid
which conforms to Fede ral Motor Vehicle
Standard "FMVSS
116 DO T 4".
The brake flu id reservoir can be difficult to
r each, therefo re , we recommend that you
have the brake fl uid changed by yo ur author­
ized
Audi d ealer. Your dea ler has the correct
too ls, 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 orig inal container
out of the reach of children!
- Brake fa ilure can result from old or inap­
propriate brake fluid. Observe these pre­
caut ions: -
Use only brake fluid that meets SAE
specification
J 1703 and conforms to
Federa l 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 f lu id is also ind icated on the
brake flu id reservoir.
- T he brake fluid must be new. Heavy use
of the bra kes ca n cause a vapo r lock if
the b rake 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. This co uld resu lt in an accident.
(D Note
Bra ke fluid will damage the paint of you r
vehicle .
(® For the sake of the environment
Because of the p rob lem of p roper disposal
of b ra ke fluid as well as the spec ial too ls
r equired and the necessary expertise, we
re commend that you have the brake fluid
changed by yo ur authorized Aud i dea ler.
Battery
General information
U nder normal ope rat ing cond itions , the bat­
tery in yo ur Audi does not need any ma inte­
nance. With
high o utside tempe ra tu res or
l ong daily drives we recommend that you have
the e lectrolyte level checked by a service fa­
cility. The electrolyte leve l should a lso be
checked each t ime the battery is charged
<=> page 243.
Have th e battery checked when yo u take your
veh icle in for service. You are well advised to
replace a battery that is o lder than S years .
With certain types of airbag deployment, the battery is disconnected from the veh icle elec­
trical system for safety reasons<=>.&
in Re­
pair , care and dispo sal of the airbags on
page
165.

242 Checking and filling
-Always wear gloves and eye protection.
Do not tilt the battery because acid
could leak out of the ventilation open­ ings.
- If you get battery acid in your eyes or
on your skin, immediately rinse with
cold water for several 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 cables .
- 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,
which could lead to damage or explosion
and personal injury .
- 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 negative ground ca­ ble.
- Before performing any work on the elec ­
trical system, switch off the engine and
ignition 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
enough to switch 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 negative cable and then
the positive cable.
- Before reconnecting the battery, make sure all electrical consumers are switch­
ed off. Reconnect the positive cable first
and then the negative cable. Never inter­
change the cables - this could start a fire! -
Never charge a frozen or a thawed-out
battery . It could explode! If a battery has
frozen, then it must be replaced. A dis­ charged battery can freeze over at 32 °F
(0 °C) .
-Make sure the vent hose is always attach­
ed to the opening on the side of the bat­
tery .
- Never use batteries which are damaged .
There is the danger of an explosion! Al ­
ways replace a damaged battery.
A WARNING ....__
California Proposition 65 Warning:
- Battery posts, terminals and related ac ­
cessories contain lead and lead com­
pounds, chemicals known to the State of
California to cause cancer and reproduc­
tive problems . Wash hands after han­
dling.
(D Note
- Do not disconnect the vehicle battery
when the ignition is on or when the en­
gine is running, otherwise , you will dam­
age electronic components in the electri­
cal system.
- If your vehicle is going to stand for a
long period of time without being driven,
protect the battery from "freezing", oth­
erwise it will be damaged and will then
have to be replaced.
- When opening the doors, the windows
lower approximately 10 mm automati­
cally. This function is not available when
the battery is disconnected, which
means there is a risk that the door seal
or the window could be damaged .

Battery charging
Starting the engine requires a well charged battery .
Fig. 194 Eng ine co mpa rtmen t: connectors for a charg ­
er a nd jump sta rt cab les
A lwa ys re ad and heed all WARNING S below
c:> &. and c:> &. in Working on the battery on
page 241 .
.. Switch off the ignit ion and all electrical con­
sumers .
.. Make sure the area is well ventilated when
you charge the battery .
.. Open the engine hood
c:> page 230 .
.. Open the red cove r on the posit ive pole
c:>fig. 194.
.. Connect the charger connectors accord ing
to the instructions to the
jump start b olts .
(Bolts under the red cover= "positive", Bolts
with hex head= "negative") .
.. Only now plug the mains lead for the charg­
ing equipmen t into the wall outlet and turn
it on
c:> 8_ .
.. Ma ke sur e t he charging rat e is not over
30 amp s/14 .8 Vol t.
.. When the batte ry is fully charged: Turn the
charging eq uipment off and remove the
ma ins lead from the wall outlet .
.. Now remove the clamps for the charging
equipment.
.. Close the red cover on the positive pole.
.. Close the hood
c:> page 2 31.
A discharged battery can free ze at tempera­
tures of on ly 32 F
0 (0 °C). A llow a frozen bat­
tery to thaw completely before attempt ing to
charge it
c:> .&. . However, we recommend not
using a thawed battery again because the bat-
Checkin g and fillin g 243
tery casing can be cracked due to ice fo rma ­
tion and can leak battery acid.
Battery charging (Maximum charging rate
of 30 amps /14.8 Volt )
When charging at low voltages (e.g. with a
trickle cha rger ), the battery cables do not
have to be disconnected f irst . The battery
caps should
not be opened when charging a
battery.
It is not necessary to remove the battery from
the luggage compartment, and it is a lso not
necessary to disconnect the cab les.
Fast ch arging the batte ry (charging rat e
a bove 14.8 V olt s)
For technica l reasons do not use a battery
charger that uses voltage greater than 14.8
Volts to charge your vehicle's battery .
A WARNING
-
Charging a battery can be dangerous .
- Always follow the operating instructions
provided by the battery charger manu­
facturer when charg ing your battery .
- Never charge a frozen battery. It may ex­
plode because of gas trapped in the ice .
Allow a frozen battery to thaw out first.
- Do not reuse batteries wh ic h were fro­
zen. The battery housing may have
cracked and weakened when the battery
froze.
- Cha rge the battery in a well ventilated
area . Keep away from open flame or elec­
trical spar k. Do not smo ke. Hyd rogen gas
generated by the battery is explos ive.
- To reduce the danger of explosion, never
connect or d isconnect charger cab les
while the charger is ope rat ing.
- Fast cha rging a batte ry is dange rous and
should only be at tempted by a compe­
tent techn ic ian wi th the prope r equip­
ment .
- Ba ttery acid that may spi ll dur ing charg­
ing should be washed off with a solution
of warm water and baking soda to neu ­
tralize the ac id.

24 4 Ch eck ing and filling
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 well
as the battery charger.
Battery replacement
The new battery must have the same specifi­
cations and dimensions as the original equip­
ment battery .
Intelligent energy management in your veh i­
cle is respons ible for d istributing the electr i­
cal energy throughout your vehicle
c::> page 202. The intell igent energy manage­
ment system w ill keep the engine battery
cha rged bette r than vehicles w ithout t his sys­
tem. To make sure the additional e lectrica l en­
e rgy is availab le once again after you have
changed the battery, we recommend that you
install batteries of the same type and man u­
facture only (the same as those installed at
the time your vehicle was delivered). Specifi­
cations are listed on the battery hous ing. Your
author ized dealer must code the battery in
the energy management system to enable you
to use the energy management funct ions cor­
rectly after replac ing the battery .
The new battery must have the same capacity ,
voltage (12-volts), amperage, const ruct ion
and p lug sealing.
When insta lling the battery, make sure the ig­
n ition and all e lectr ica l consumers are sw itch ­
ed off .
{[) Note
Make sure the venti lation hose on the s ide
of the battery is connected, ot herwise
fumes or battery ac id can leak out.
- Vehicles with the Start-Stop-System* are
equipped with a special cycle-proof AGM
batte ry. Insta lling a differe nt type of
batte ry can ca use p rob lems in the vehi­
cle elect rical system. When rep lacing the
vehicle bat tery, always ins ta ll one wi th the same specifica
tions as the o rigina l
battery .
~ For the sake of the env ironment
B ec ause o f th e p rob lem of p roper disposal
of a battery, we recommend your author­
ized Audi dealer change the battery fo r
you. Batteries contain sul fur ic acid and
l ead and must always be disposed of prop­
erly in compl iance with all environmental
regulations. Disposing of veh icle batter ies
i mproperly is very dange rous to the envi­
r onment.
Windshield/headlight
washer container
Fi g. 195 Eng in e compa rt m ent: cove r on t he w inds hield
and head lig ht* was her flu id reservo ir
T he washer fluid co nta iner is mar ked w ith the
symbol$ on its cap
c::> fig. 195, c::> fig. 189.
.,. Before yo u check anything in the engine
compa rtment,
alwa ys read and heed all
WARNINGS
c::> A in Working in the engine
compartment on page 230 .
.. Lift the fi ller cap tongue to add washer flu­
id . You can fi ll the containe r to the top .
.. Press the cap back onto the filler neck after
filling the container .
You can find the reservoi r
capacity in the table
in
c::> page 287.
C lean water should be used when filling up . If
possible, use soft water to prevent scaling on
washe r jets. Always add a g lass cleaner so lu­
t ion (with frost protection in the winter).

(D Note
Do not mix engine coolant antifreeze or
any other add itives to fi ll u p the w ind­
shie ld washer reservoir.
Checkin g and fillin g 245
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