radiator cap AUDI A5 2008 8T / 1.G Owners Manual

Instruments and warning/indicator lamps 12Warning symbol in instrument cluster

If the symbol
 lights up in the display, this means that either the
coolant temperature is too high or the coolant level is too low
⇒page 32.
If the needle is at the top end of the dial, this means the coolant
temperature is too high. Stop the vehicle, switch off the engine and
wait for it to cool down. If the warning lamp starts flashing again
after just a short distance, contact a qualified workshop.
WARNING
•
Before opening the bonnet and checking the coolant level,
please observe the warning information on ⇒page 231, “Working
on components in the engine compartment”.
•
Never open the bonnet if you can see or hear steam or coolant
escaping from the engine compartment; there is a risk of being
scalded. Wait until you can no longer see or hear escaping steam
or coolant.Caution
•
Additional lights and other accessories in front of the air inlet
reduce the cooling effect of the radiator. At high outside tempera-
tures and high engine loads, there is a risk of the engine over-
heating.
•
The front spoiler also ensures proper distribution of the cooling
air when the vehicle is moving. If the spoiler is damaged this can
reduce the cooling effect, which could cause the engine to overheat.
You should obtain professional assistance.
Rev counter
The rev counter indicates the number of engine revolu-
tions per minute.You should select a lower gear if the engine speed drops below
1500 rpm. The start of the red zone on the dial indicates the
maximum engine speed which may be used briefly when the engine
is warm and after it has been run in properly. However, it is advisable
to change up a gear or move the selector lever to “D” (or lift your
foot off the accelerator) before the needle reaches the red zone.
Caution
Never allow the rev counter needle ⇒page 11, fig. 2 to go into
the red zone on the dial for more than a very brief period: there is a
risk of damaging the engine. The start of the red zone on the dial is
different for some engine versions.
For the sake of the environment
Changing up a gear early will help you to save fuel and minimise
engine noise.
button
This button has a number of different functions.
A2
SET
Fig. 3 Instrument
cluster: SET button
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Checking and topping up fluids231
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Working on components in the engine compartment
Extra caution is necessary when working on components
in the engine compartment.Always be aware of the danger of injury and scalding as well as the
risk of accident or fire when working in the engine compartment
(e.g. when checking and refilling fluids). Always observe the warn-
ings listed below and follow all normal safety precautions. The
engine compartment of any motor vehicle is a potentially
hazardous area. ⇒.
WARNING
•
Switch off the engine.
•
Remove the ignition key.
•
Apply the parking brake.
•
Put the gear lever in neutral or selector in P.
•
Wait for the engine to cool down.
•
Keep children away from engine compartment.
•
Never spill fluids on hot engine components. These fluids can
cause a fire (e.g. radiator anti-freeze).
•
Take care not to cause short circuits in the electrical system,
especially when working on the battery.
•
Do not touch the radiator fan when the engine is hot. The fan
may start running suddenly.
•
Do not unscrew the cap on the expansion tank when the engine
is hot. The cooling system is under pressure.
•
Protect face, hands and arms by covering the cap with a large,
thick rag to protect against escaping coolant and steam.
•
If any tests have to be performed with the engine running,
there is an extra safety risk from the rotating parts, such as the
drive belts, alternator and radiator fan, etc., and from the high-
voltage ignition system.
•
Vehicles with automatic gearbox: Never open the throttle inad-
vertently (for instance by hand from the engine compartment) if a
gear is engaged while the vehicle is stationary with the engine
running. The vehicle could otherwise start moving immediately
and possibly cause an accident.
•
Observe the following additional warnings if work on the fuel
system or the electrical system is necessary:
−Always disconnect the battery.
−Do not smoke.
−Never work near naked flames.
−Always keep an approved fire extinguisher immediately
available.Caution
When topping up fluids make sure the correct fluid is put into the
correct filler opening. This can otherwise cause serious malfunc-
tions or engine damage.
For the sake of the environment
Inspect the ground underneath your vehicle regularly so that any
leaks are detected at an early stage. If you find oil spots or other
fluids, have your vehicle inspected by a qualified workshop.
Note
On right-hand drive vehicles* some of the containers/ reservoirs
mentioned below are located on the other side of the engine
compartment.
WARNING (continued)
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Checking and topping up fluids 232Closing the bonnet– To close the bonnet, pull it down to overcome the spring
pressure.
– Then let it drop into the catches; do not press down ⇒.
WARNING
•
For safety reasons the bonnet must always be completely
closed when the vehicle is moving. After closing it always check
that it is properly secured. The bonnet must be flush with the adja-
cent body panels.
•
Should you notice that the bonnet is not safely secured when
the vehicle is moving, stop the vehicle immediately and close the
bonnet properly, otherwise it could cause an accident.
Engine compartment layoutEngine compartment layout
Main components for checking and refillingFig. 223 Typical locations of fluid containers, engine oil dipstick and engine oil
filler cap
Jump-start terminal (+) under a cover . . . . . . . . . . . . .
Brake fluid reservoir (
) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil filler cap (

) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil dipstick (orange) . . . . . . . . . . . . . . . . . . . . . .
Radiator expansion tank () . . . . . . . . . . . . . . . . . . . . .
Windscreen washer container (
) . . . . . . . . . . . . . . . .
Jump-start terminal (-) with hexagon head . . . . . . . . .
Hydraulic fluid reservoir for power steering . . . . . . . .
A1
241, 266
A2
238
A3
234
A4
234
A5
236
A6
242
A7
241, 266
A8
201
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Checking and topping up fluids 236otherwise this would reduce the antifreeze protection. In addition,
the cooling effect will be adversely affected.
Vehicles for export to countries with a cold climate (such as Sweden,
Norway and Finland) are supplied with antifreeze protection down
to about -35 °C. The concentration of the antifreeze additive for
these countries should always be at least 50%.
Caution
•
It is advisable to have the cooling system checked before the
winter season to make sure that the antifreeze concentration is
adequate for the conditions to be expected. This applies particularly
if you intend to take the car into a colder climate zone. If necessary,
have the anti-freeze concentration increased to 50 - 60% as required.
•
Use only anti-freeze additive G12+, an additive meeting the spec-
ification “TL-VW 774 F ”. Other additives may give considerably infe-
rior corrosion protection. The resulting corrosion in the cooling
system can lead to a loss of coolant, causing serious damage to the
engine.
•
The coolant additive G12+ can be mixed only with additives G11
and G12.
Checking coolant level
The coolant level can be checked at a glance.
– Switch off the ignition.
– Read off coolant level on radiator expansion tank
⇒fig. 227. When the engine is cold it should be between
the “MIN” and “MAX” marks. When the engine is hot it
may be slightly above the “MAX” mark.The coolant level should be checked with the engine switched off.
The coolant level is monitored by a warning lamp in the instrument
cluster ⇒page 32. However, we recommend that it should be
checked occasionally.
Coolant losses
Any loss of coolant normally indicates a leak in the cooling system.
In this case the cooling system should be inspected by a qualified
workshop without delay. It is not sufficient merely to top up the
coolant.
If there are no leaks in the system, a loss of coolant can only occur
if the coolant boils and is forced out of the system as a result of
overheating.
Caution
Radiator sealants must not be added to the coolant. Such additives
could seriously impair the function of the cooling system.Topping up the coolant
Be careful when topping up coolant.– Switch off the engine.
– Wait for the engine to cool down.
– Cover the cap on the expansion tank ⇒fig. 227 with a
cloth, and carefully unscrew the cap anti-clockwise
⇒.
Fig. 227 Engine
compartment: Mark-
ings on radiator expan-
sion tank
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Checking and topping up fluids237
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Add coolant.
– Screw the cap on again tightly.Make sure that the coolant meets the required specifications
⇒page 235, “Coolant”. Do not use a different type of additive if anti-
freeze additive G12+, G12 or G11 is not available. In this case use
only water and bring the coolant concentration back up to the
correct level as soon as possible by putting in the specified additive.
Always top up with fresh, unused coolant.
Do not fill above the “MAX” mark. Excess coolant is forced out of the
system through the valve in the filler cap when the engine gets hot.
If a lot of coolant has been lost, wait for the engine to cool down
before putting in cold coolant. Failure to do so could result in
serious engine damage.
WARNING
•
The cooling system is under pressure. Do not unscrew the cap
on the expansion tank when the engine is hot: you could be
scalded by escaping steam
•
The coolant and coolant additive can be a health hazard. Store
the coolant additive in the original container in a safe place out of
reach of children – risk of poisoning.For the sake of the environment
Drained off coolant should not be used again. Drain off the used
coolant into a suitable container and dispose of it in the proper
manner (observe environmental regulations).
Radiator fan
The radiator fan can start running spontaneously.The radiator fan is driven by the engine via a poly V-belt. The speed
of the fan is varied by a viscous clutch according to the temperature.
There is also an auxiliary electric fan, which cuts in automatically
whenever the temperature of the coolant and the engine compart-
ment rises above a certain level.
The auxiliary fan can continue to run for as long as 10 minutes after
stopping the engine – even after the ignition is switched off. It may
also start running suddenly ⇒ after a while if•
residual heat raises the coolant temperature, or
•
the hot engine compartment is additionally heated up by the
sun.
WARNING
When working in the engine compartment be aware that the radi-
ator fan may start running suddenly – risk of injury.
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Checking and topping up fluids 242Replacing the battery
A replacement battery must have the same specifications
as the original equipment battery.Your vehicle is equipped with an intelligent power management
system to control the distribution of electrical energy ⇒page 202.
The power management function ensures that the battery is
charged much more efficiently than on vehicles without a power
management system. For this additional power to be available after
replacing the battery, we recommend that the replacement battery
used is of the same make and type as the original-equipment
battery. The battery must be encoded in the control unit for power
management. This has to be done by a qualified workshop.
A replacement battery must have the same capacity, voltage (12 V)
and current rating. It must also have the same dimensions as the
original, factory-fitted battery and have sealed caps. The battery
must comply with the standards TL 825 06 (dated December 1997 or
later) and VW 7 50 73 (August 2001 or later).
Caution
•
Make sure that the vent hose is always attached to the opening
on the side of the battery. Gases or battery acid can otherwise
escape and possibly cause damage.
•
The battery holder and clamps must always be correctly secured.
•
Before starting any work on the battery, always observe the
warnings listed under ⇒page 240, “Important safety warnings for
handling a car battery”.For the sake of the environment
 Batteries contain toxic substances including sulphuric acid and
lead. They must be disposed of appropriately and must not be put
together with ordinary household waste. Make sure the battery
removed from the vehicle cannot tip over. Otherwise, sulphuric acid
could escape.
Windscreen washerPlain water on its own is not sufficient for the windscreen
washer system.The container for the windscreen washer
 contains the cleaning
fluid for the windscreen and the headlight washer system*
⇒fig. 230. Container capacity: ⇒page 293.
Plain water on its own is not enough to clean the glass properly. It
is therefore advisable to add a suitable washer fluid additive (with
wax solvent) to the water. A washer fluid with freeze-resistant addi-
tive should be used in winter.
Caution
•
Never put in radiator anti-freeze or other additives.
•
Never use washer fluid which contains paint thinners or solvents
as it can damage the paintwork.
Fig. 230 Engine
compartment: Wind-
screen washer
container
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