engine AUDI TT ROADSTER 2008 Manual Online

___ C_h_ e_ c_k _in --== g'-- a_n _d_ f_il _li _n ..:::g:::..- ___________________________________________ _
function and performance of your cooling system and could result
in damage not covered by your New Vehicle Limi ted Warranty .•
Checking the engine coolant level
The engine coolant level can be checked with a quick
g lance .
Fig. 154 Engin e
co mpartment : coo lan t
e xpansio n tank
Before you check anything in the engine compartment,
always read and heed all WARNINGS =>
& in "Working in
the engi ne compa rtment" on
page 2 20.
- Switch t he ignition off.
- Rea d the coo lan t leve l at th e co ola nt e xpansion tank
=> fig . 154. Wit h a c old engine , it must be a b ove the
"min" mark . With a hot engine, it can be a little a bove t he
indicated range .
The location of the coo lant expansion tank can be seen in the
engine compartment i llustration.
To obtain an accurate reading, the engine must be switched off .
The expans io n tank in your vehicle is equipped with an electric
coo lant level sensor . When the coolant leve
l is too low , the warning light in the Auto­
Check System ~
page 32will blink un til you add coolant and the
level has been restored to normal. Even though there is an electric
coo lant level sensor, we still recommend you check the coolant level
from time to time .
Coolant los s
Coolant loss may indicate a leak in the cooling system . In the event
of coo lant loss, the cooling system should be inspec ted i mmedi ­
a tely by your authorized Audi dealer . It is no t enough mere ly to add
coolant.
In a
sealed system, losses can occur only if the boi ling point of the
coolant is exceeded as a result of overheating.
0 Note
Do not add any type of radiator leak sea lant to your vehicle's engine
coo lant. A dding ra diator repair fluid may adversely affec t the func ­
tion and performance of your cooling system and could result in
damage not cove red by your New Veh icle Limi ted War ranty. •
Adding coolant
Be very careful when adding en gine coolant.
Before you c heck anything in the engine compartment,
always read and heed all WARNINGS =>
& in "Working in
the eng ine compa rtment" on
page 220 .
-Turn off the engine.
- Let the engine coo l dow n.
- Place a t hick rag
over th e coola nt expansio n tank
=> fig . 154 and carefully twist the cap cou nter -c lockwise
=> & .
- Add coolant .

___________________________________________ C_ h_e _c_ k_ i_n _g _ a_n _d_ f_il _li _n _g __ ffllll
•
- Twist the cap on again tightly.
Replacement engine coolant must conform to exact specifications
=>
page 227, "Coolant ". If in an emergency coolant additive G12 + is
not avai lab le, do
not use a d ifferen t addit ive. Use p lain water
instead until you can get the correct additive and can restore the
correct ratio . This should be done as soon as possib le .
If you have lost a considerable amoun t of coolant, then you should
add cold antifreeze and cold water only when the engine is cold.
Always use
new engine coolan t when refilling .
Do not fi ll coolant above the "MAX" mark. Excess coo lant will be
forced out through the pressure relief va lve in the cap when t he
engine becomes hot.
& WARNING
• The cooling system is under pres sure a nd can g et very hot.
Reduce the ri sk of scald ing from ho t co olant b y following the se
s tep s.
- Turn off the engine and allow it to cool d own .
- Prote ct your fa ce , hand s and arm s from e scaping fluid and
st eam b y covering the cap with a l arge , thick rag .
- Turn the cap slo wly and very carefully in a count er-c lockw ise
dire ction while applying light , do wnward pres sure on th e top
o f the cap.
- To avoid b eing burned , do not spill antifre eze or coolant on
th e ex haus t syste m or hot e ngine parts . Under cert ain co nd i­
tion s, the eth yle ne gly col in en gine co ola nt can cat ch fire .
• Antifr ee ze is poison ous. Alw ay s s tore antifr ee ze in its origi nal
c ontainer and well out of the re ach of children.
• If you dr ain th e coola nt , it mu st be caught and safe ly stored in
a proper contain er cle arly m ark ed "p oison ".
0 Note
• Coolant po llutes the env ironment and could cause an engine
fire . Excess coo lant wil l be forced out through the pressure relief
valve in the cap when the engine becomes ho t.
• I f, in an emergency, only water can be added, the correct ratio
between water and antifreeze=>
page 227must be restored as soon
as possib le .
<£> For the sake of the environment
Drained coolant should not be reused . Always dispose of used
coolant while observi ng all environmental regulations. •
Radiator fan
The radiator fan switches on automatically by itself.
The electric radiator fan is controlled by thermoswitches that switch
on and off depending on coolant and engine compartment temper­
atures.
An auxiliary electric radiator fan * switches on and off depending on
coolant temperature and other vehic le operation conditions .
After you switch the eng ine o ff, the aux iliary 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 due to the heat
build -up from the engine in the engine compar tment, or
• the engine compartment heats up because the vehicle is parked
in intense sunlight.
& WARNING
• To reduc e the ri sk of per sonal in jur y nev er t ouch t he radiato r
f a n . .,_
Vehicle care
I t •

___ C_h_ e_ c_k _in --== g'-- a_n _d_ f_il _li _n ..:::g:::..- ___________________________________________ _
& WARNING (continued)
• 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 automatically 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. 155 Engine
compartment: brake
fluid reservoir
Before you check anything in the engine compartment,
always read and heed all WARNINGS =>
& in "Working in
the engine compartment" on
page 220.
- Read the brake fluid level from the brake fluid reservoir
~ fig. 155. The brake fluid level must be between the
"MIN" and "MAX" markings.
The brake fluid reservoir is located behind the rear partition of the
engine compartment on the left side~
page 221 .
The fluid level may drop slightly after some time due to the auto­
matic adjustment of the brake pads. This is not cause for alarm.
If the brake fluid level falls
considerably below the "MIN" mark, the
brake warning/indicator light (U .S. models:
BRAKE , Canadian models:
ill) will come on~ page 20 and~ page 32. Do not continue to
operate the vehicle . The complete brake system should be thor­
oughly checked by an authorized Audi dealer or other qualified
facility and the cause corrected. If the brake fluid level is too low, the
brake warning/indicator light will illuminate. Contact an authorized
Audi dealer
immediately .•
Changing brake fluid
Have the brake fluid changed by an experienced techni­
cian.
Brake fluid absorbs moisture from the air. If the water content in the
brake fluid is too high, corrosion in the brake system may result
after a period of time. The boiling point of the brake fluid will als o
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 Stan ­
dard "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 autho­
rized
Audi dealer . Your dealer has the correct tools, the right brake
fluid and the know -how to do this for you.
& WARNING
• Brake fluid is poisonous. It must be stored only in the closed
original container out of the reach of children!
• Brake failure can result from old or inappropriate brake fluid.
Observe these precautions : .,,_

Checkin g and fillin g ---------------~-!':WIii
•
& WARN ING (co ntinued)
- Use only br ake flu id th at m eet s SAE spec ificati on J 1703 and
c onf orms to F ed eral Motor Vehi cle St and ard 11 6. Always ch ec k
w ith your a uthori zed A ud i de aler to m ake sure you are u sin g
the corre ct brake fluid . Th e co rrect typ e of br ake fluid i s also
indic ate d on the br ake fluid res ervo ir .
- The br ake fluid mu st be ne w. Heavy u se of the br ake s c an
c au se a vapor lo ck if the brake fluid i s left in the s yste m too
long. Thi s ca n seriou sly affe ct the eff iciency of the brake s as
w ell as your safety . This could resu lt in an a ccident .
0 Note
Brake fluid wi ll damage the paint of your vehicle.
Because of the prob lem of proper disposal of brake fluid as well as
t he special too ls required and the necessary expertise, we recom­
mend that you have the brake f luid changed by your authorized Audi
dea ler .•
Battery
General information
Your vehicle is equipped with a specia l battery, an AGM battery. This
battery is located in the luggage compartment and must be
replaced with an origina l equipment battery. Under normal oper ­
ating conditions, the battery is
maintenan ce-free .
Have the battery checked when you take your vehicle in for service.
You a re we ll advised to replace a battery that is olde r th an 5 years .
Disc onn ectin g th e batt ery t erm inal s
Some vehic le functions (power window regulators, for e xample) are
lost if the battery terminals are disconnected. These functions have
to be relearned after the batte ry term inals are connected again. To
prevent this, the battery should only be disconnected from the
vehicle electrical system when abso lutely necessary for repairs.
V ehi cle s not dri ven for long period s
If you are going to le t your vehicle stand for a long t ime a nd not
drive it, you should remember there are electrica l components
which are still functioning and they will draw energy from the
battery and drain it, for examp le, the engine immob ilizer. To prevent
this, you can either charge the battery occasionally to keep it in
good working condition or you can d isconnect the negative cab le
on the battery.
W inter op era ti on
During the winter months, battery capacity tends to decrease as
temperatures drop. This is because more power is a lso consumed
while starting, and the headlights, rear window defogger, etc., are
used more often .
Avoid unnecessary power consumption, particularly in city traffic or
when trave ling on ly shor t distances . Let your au thorized Audi dea ler
check the capacity of the vehicle battery before winter sets in
=>
page 235 . A well charged battery will not on ly prevent start ing
p rob lems when the weather is cold , but wi ll a lso last longer .
Replacing battery
The new battery must h ave the same capacity, voltage (12 volts},
amperage, construction and p lug sea ling, as the origina l battery.
Specifications are l isted on the battery hous ing. Batteries specially
developed by Audi fulfill the ma intenance, output, and safety
requirements.
When installing the battery, make sure the ignition and all electrical consumers are switched off=>
0. .,_
Vehicle care I t •

-Ch
ecking and filling ---=-----=----------------
We recommend that you use maintenance -free or cyc le- resis­
tant /leak -pr oof
batteries according to the standards TL 825 06 (from
December 1997) and VW 7 50 73 (from Augus t 2001 ).
Replacing the battery should be carried by a qualified workshop.
P lease follow the instructions on the battery cover.
0 Note
• All work on the battery requires technical knowledge. Please
contact an Audi dealership or another authorized facility for ques­
tions about the battery- danger of acid bu rns and explosion hazard!
• The battery must not be opened! Do not try to change the
battery's liquid level, otherwise detonat ing gas wil l escape from the
battery - explosion ha zard!
• The AGM battery in the luggage compartment cannot leak,
because the electrolyte for this battery is absorbed into a special
g lass mat . This leak-proof battery must not be rep lace with a
conventiona l battery .
• Make sure the ventilation hose on the side of the battery is
connected, otherwise fumes or battery acid can leak out.
• Battery holde r and terminals always have to be secured correctly .
• Before al l wo rk on the battery follow the
warning s below :::> & in
" Working on the battery" on page
232.
~ For the sake of the environment
Because of the problem of proper d isposal of a battery, we recom­
mend your authorized Audi dea ler change the battery fo r you.
Batteries contain sulfur ic acid and lead and must always be
disposed of properly in compliance with all environmental regula ­
t ions . Di sposing of vehicle batteries i mproper ly is very dangerous to
the environment. Make sure that the removed battery cannot over ­
ba lance, otherwise sulfur ic acid migh t escape!
[ i ] Tips
If your ve hic le is left standing for several weeks at extremely low
temperatures, the vehicle battery should be removed and stored
where it will no t free ze. This will preven t it from being damaged and
having to be replaced. •
Working on the battery
Be especially care ful w hen wor king o n or nea r the
battery!
Fig . 156 Luggag e
co mp artment : AGM
batte ry
The batte ry is loca ted in the lu g ga ge compartmen t.
- Sw ing up t he luggage compartmen t floo r.
Remove the cover p late b y tu rning the t humbw heel.
The positive (+) battery term ina l is protected by a pla stic cover . This
cover must be removed to access the positive( +) terminal when
connecting jumper cab les to start the engine.
Always heed the
safety w arnings , when working on the vehicle
battery or the vehicle electrical system to prevent injury.

__________________________________________ C_ h _ e_c _k _in _ g =- a_ n __ df _i_ lli _n ___ g __ __
•
The following WARNINGS are very important when
working on the battery:
Always heed the following WARNING SYMBOLS and safety pre­
cautions when working on the battery .
Always wear eye protection.
Battery acid contains sulfuric acid. Always 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 chil ­
dren.
& WARNING
Whenever working on the battery or on the electrical system,
there is the risk of injury, accident and even fire. Read and heed the
following WARNINGS:
• Always wear eye protection. Do not let battery acid or any lead
particles get on your skin or clothing. Shield your eyes. Explosive
gases can cause blindness or other injury.
• Battery acid contains sulfuric acid. Sulfuric acid can cause
blindness and severe burns.
- Always wear gloves and eye protection. Do not tilt the
battery because acid could leak out of the ventilation openings.
- If you get battery acid in your eyes or on your skin, immedi­
ately rinse with cold water for several minutes and get medical
attention.
& WARNING (continued)
-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 negative 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 system, disconnect the
negative ground cable.
• Before performing any work on the electrical system, switch off
the engine and ignition as well as any electrical equipment. The
negative cable on the battery must be disconnected.
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 disconnect the negative
cable and then the positive cable.
• Before reconnecting the battery, make sure all electrical
consumers are switched off. Reconnect the positive cable first and
then the negative cable . Never interchange 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
discharged battery can freeze over at 32 °F (0 °CI. .,,_
Vehicle care
I t •

___ C_h_ e_ c_k _in --== g'-- a_n _d_ f_il _li _n ..:::g:::..- ___________________________________________ _
& WARNING (continued)
• Make sure the vent hose is always attached to the opening on
the side of the battery.
• Never use batteries which are damaged. Danger of explosion!
Always replace a damaged battery .
& WARNING
California Proposition 65 Warning :
• Battery posts, terminals and related accessories contain lead
and lead compounds, chemicals known to the State of California
to cause cancer and reproductive problems. Wash hands after
handling .
0 Note
• Do not disconnect the vehicle battery when the ignition is
switched on or when the engine is running, otherwise, you will
damage electronic components in the electrical system.
• When working on the engine, protect the battery housing from
ultraviolet (UV) rays by not parking the vehic le in direct sunlight.
• 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 replaced. •
Checking the battery acid level on magic eye
batteries*
The battery acid level in the battery can be checked
through the clear inspection window.
I
Fig. 157 Luggage
compartment : Battery
with magic eye.
On top of the battery, there is a round "window". This
window (magic eye) changes color as the battery charge
and acid level change.
- Read and heed all WARNINGS=>
& in "Working on the
battery" on
page 232
- Read the acid level from the window on the battery
=> fig. 157.
Air bubbles in the window can cause an inaccurate reading. Care ­
fully tap on the side of the window.
• If the window is
green, the battery acid level is correct.
• If the window has
no color or is bright yellow, the battery acid
level is too low. Have the battery tested by your authorized Audi
dealer or a qualified workshop.
• If the window is
black , then the battery is insufficiently charged.
Recharge the battery as soon as possible =>
page 235. ...

Checking and filling -
------------- --------=----" =---------
0 Note
Do not overfill the battery, otherwise battery acid will overflow
through the vent opening. This can damage the paint and cause
corrosion. •
Checking the battery acid level on
conventional batteries *
The acid level of a conventional battery can be checked
visually.
Fig. 158 Battery : Elec­
trolyte level
-Check the electrolyte level on the front of the battery. The
level should be between the "MIN" and "MAX" markings.
If the electrolyte level is below the "MIN" level, have an authorized
workshop fill the battery cell with
distilled water.•
Charging of battery
Starting the engine requires a well charged battery.
-Always read and heed all WARNINGS below => & and
=> & in "Working on the battery" on
page 232.
- Switch off the ignition and all electrical consumers. - Make sure
the area is well ventilated when you charge
the battery.
- Connect charger cables.
ALWAYS connect charger cables
POSITIVE
(v to POSITIVE (v ; NEGATIVE Q to NEGATIVE
o.
- Switch on the charger.
- Make sure the charging rate is not over 6 amps.
- Turn off the charger=>&.
- Disconnect the charger cables.
- Connect both battery cables to the battery if necessary -
first plus, then minus.
It is not necessary to remove the battery from th e engine compart­
ment, and it is also not necessary to disconnect the cables.
Normally, a battery should be charged at no more than 10 percent
of its rated capacity .
For example, a charging current of 4.5 amps would be used on a
battery rated at 45 Ah. Rated capacity of the battery in your vehicle
is listed on the battery housing.
The battery caps should
not be opened when charging a battery.
& WARNING
Charging a battery can be dangerous.
• Never charge a frozen battery. It may explode because of gas
trapped in the ice . Allow a frozen battery to thaw out first.
• Do not reuse batteries which were frozen. The battery housing
may have cracked and weakened when the battery froze .
• Charge the battery in a well ventilated area. Keep away from
open flame or electrical spark. Do not smoke. Hydrogen gas gener-
ated by the battery is explosive. .,_
Vehicle care I I irechnical data

___ C_h_ e_ c_k _in --== g'-- a_n _d_ f_il _li _n ..:::g:::..- ___________________________________________ _
& WARNING (continued)
• To reduce the danger of explosion, never connect or disconnect
charger cables while the charger is operating.
• Fast charging a battery is dangerous and should only be
attempted by a competent technician with the proper equipment.
• Battery acid that may spill during charging should be washed
off with a solution of warm water and baking soda to neutralize
the acid.
0 Note
Never use a fast charger as a booster to start the engine. This will
seriously damage sensitive electronic components , such as control
units, relays, radio, etc., as well as the battery charger.
[ i ] Tips
The vehicle battery must not be charged with a standard small
charger that plugs into the cigarette lighter or outlet .•
Windshield /headlight washer
container
Using plain water is not adequate for filling the wind­
shield washer system and the headlight washer system*.
Fig . 159 Fender, left:
Windshield washer
fluid reservoir
The washer fluid container is marked with the symbol e.;. on
its cap.
- Before you check anything in the engine compartment,
always read and heed all WARNINGS=> & in "Working
in the engine compartment" on
page 220.
-Lift the filler cap tongue to add washer fluid. You can fill
the container to the top.
- Press the cap back onto the filler neck after filling the
container .
You can find the reservoir capacity in the table in~ page 291.
Use winterized windshield washer solvent during the cold season
even though the vehicle is equipped with heated washer jets. It
helps to keep your windshield clean and prevents the fluid from
freezing in the winter.
Follow the directions on the container for the correct amount to be
used.
~

___________________________________________ C_ h_e _c_ k_ i_n _g _ a_n _d_ f_il _li _n _g __ fflllll
•
0 Note
Do not mix engine coo lant antifreeze or any other addit ives to fill up
the windshield washer reservoir. •
Vehicle care I t •