2008 AUDI A5 engine overheat

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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Instruments and warning/indicator lamps19
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Electro-mechanical parking brake

This warning lamp monitors the electro-mechanical
parking brake.The warning lamp
 lights up when the parking brake is applied
with the ignition on. After the ignition has been switched off the
lamp will stay on for about 30 seconds. The warning lamp will light
up for about 30 seconds if the parking brake is applied with the igni-
tion switched off.
The warning lamp should go out when the parking brake is released.
If the warning lamp flashes continuously after the parking brake has
been applied, the brake may not be strong enough to hold the
vehicle on a slope. This may be due to the brakes overheating.
Please note the following points:
•
If the gradient is too steep to park the vehicle safely, the display
will show the message Caution: Vehicle parked too steep.
•
In the event of a fault in the parking brake system the symbol

will also appear in the instrument cluster display together with the
message Parki ng b rake! You should have the fault corrected by a
qualified workshop without delay.
Brake system

The warning lamp flashes if the brake fluid level is too low
or if there is a fault in the ABS system or the parking
brake.If the warning lamp
 flashes, there is a fault in the brake system.
The symbol
 in the instrument cluster display will flash at the
same time. You can press the button to obtain a message
explaining the fault ⇒page 31.
If a failure should occur in the ABS, the ABS warning lamp
 will
light up together with the brake warning lamp
 ⇒.
WARNING
•
Before opening the bonnet and checking the brake fluid level,
observe the warning information on ⇒page 231, “Working on
components in the engine compartment”.
•
If the brake warning lamp does not go out, or if it lights up
when driving, the brake fluid level in the reservoir is too low – this
may cause an increased accident risk. Stop the vehicle and do not
drive on. You should obtain professional assistance.
•
If the brake warning lamp lights up together with the ABS
warning lamp, this can mean that the control function of the ABS
is out of action. As a result the rear wheels can lock relatively
easily when braking. This could cause the tail of the vehicle to skid
sideways. Drive carefully to the nearest qualified workshop and
have the fault rectified.
Fuel gaugeThe gauge only works when the ignition is switched on.
When the needle reaches the reserve zone, the symbol
 lights up
in the instrument cluster display ⇒page 36 together with the
message Please refuel. At this point there are still about 8 litres of
fuel left in the tank. This is your reminder to fill up soon.
The tank capacity of your vehicle is given in the Technical data
section ⇒page 293.
Caution
Never run the tank completely dry. If there is an irregular fuel supply,
misfiring can occur. This allows unburnt fuel to enter the exhaust
system, which could cause overheating and damage the catalytic
converter.
SET
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Driver information system 32
Parking brake ! Please contact workshop
– If the symbol appears after you switch on the ignition
when the vehicle is stationary, please check whether you
can release the parking brake. If this is possible, you
should drive without delay to the nearest qualified work-
shop and have the fault rectified. If the parking brake
cannot be released you should obtain professional
assistance.
– If this symbol should appear while driving, there may be
a malfunction in the drive-away assist or the emergency
brake functions. You may not be able to apply the parking
brake. It is also possible that you cannot release the
parking brake after it has been applied. Drive the vehicle
to a qualified workshop and have the fault repaired.If the ABS fails, the ABS warning lamp
 will light up together with
the brake warning symbol
 ⇒.
WARNING
•
Before opening the bonnet and checking the brake fluid level,
observe the warning information on ⇒page 231, “Working on
components in the engine compartment”.
•
If the brake fluid level in the reservoir is too low, this could
result in an accident. Do not drive on. You should obtain profes-
sional assistance.
•
If the brake warning lamp lights up together with the ABS
warning lamp, this can mean that the control function of the ABS
is out of action. As a result the rear wheels can lock relatively
easily when braking. This could cause the tail of the vehicle to skid
sideways. Drive carefully to the nearest qualified workshop and
have the fault rectified.
Note
The warning lamp
 in the instrument cluster will start flashing as
well if there is a fault in the brake system.
Fault in the cooling system

Faults in the cooling system must be rectified immedi-
ately.If the
 symbol flashes in the display, this means that
either the coolant temperature is too high or the coolant
level is too low. The symbol is accompanied by a driver
message giving you more information about the fault. This
message will disappear after about 5 seconds, but you can
call it up again at any time by pressing the button:
Switch off engine, check coolant level
–Stop the vehicle.
– Switch off the engine.
– Check the coolant level ⇒page 236.
– Add more coolant if necessary ⇒page 236.
– Wait for the symbol to go out before driving on.
– Obtain professional assistance if necessary.
If the coolant level is correct, the overheating may be caused by a
malfunction of the radiator fan.
If the alternator warning lamp lights up as well ⇒page 31, it is
possible that the drive belt has broken.
SET
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Seats and storage89
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Insert the plug of the electrical appliance into the socket.Electrical equipment can be connected to the 12 Volt socket. The
appliances connected to the socket must not exceed a power rating
of 100 W.
WARNING
The electrical sockets and any appliances connected to them will
operate only when the ignition is switched on. Improper use of the
electrical sockets or the appliances connected to them can cause
injuries or fire. To avoid the risk of injury, never leave children
unsupervised in the vehicle with the key.
Caution
•
To avoid damage to the vehicle's electrical system, never
connect equipment that generates electrical current, such as a solar
panel or battery charger, to the 12 Volt sockets or cigarette lighter in
order to charge the vehicle's battery.
•
Use only equipment which has been tested for electromagnetic
compatibility in compliance with EC Directive 2004/104/EC.Note
Using electrical appliances with the engine switched off will drain
the battery.
Applies to vehicles: with 230 Volt Euro socketOn-board 230 Volt Euro socketElectrical equipment can be connected to the 230 Volt
Euro socket in the rear centre console.The 230 Volt Euro socket can only be used when the engine
is running ⇒.
– Fold up the lid to access the socket.
– Plug the Euro connector into the socket. This will auto-
matically release the child safety device.LED in electrical socket
Appliances suitable for connection
Electrical equipment with a Euro plug connector can be connected
to the 230 Volt Euro socket. The appliances connected to the
230 Volt Euro socket must not exceed a power rating of 150 W
(300 W peak power).Steady green light:
The socket is ready for use.
Flashing red light:
The socket has tripped out due
to a power surge, overheating or
similar
Fig. 103 Rear centre
console: 230 Volt Euro
socket
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Seats and storage 90If you connect more than one appliance, the total power rating of all
appliances must not exceed 150 W. If necessary, check the type
plates on the connected appliances for details of the power ratings.
Connected appliances must be in perfect condition and free of
defects.
WARNING
•
Heavy appliances or plugs (such as power supply units) can
damage the mounting of the 230 Volt Euro socket if they are
suspended directly from the socket – Risk of injury!
•
Make sure that all connected appliances are securely stowed
when driving to prevent them from being catapulted through the
car under braking or in an accident – Danger to life!
•
Never spill liquid over the socket – Danger to life! If the socket
does get wet, ensure that it is absolutely dry before using it again.
•
Improper use of the electrical socket or appliances connected
to it can cause injuries or fire – Risk of injury!
•
Never leave children unattended in the vehicle while the engine
is running – Risk of injury!
•
Connected appliances behave differently than when they are
connected to the public electricity grid. As a result, the connected
appliances may become hot during operation – Risk of injury!
•
When using adapters or extension cables, please remember
that the child safety device on the 230 Volt Euro socket is deacti-
vated and the socket is live – Risk of injury!
•
Do not insert conductive materials, such as knitting needles,
into the contacts of the 230 Volt Euro socket – Danger to life!
•
Switch off the connected electrical appliances if the inverter
trips out due to overheating – Risk of injury!Caution
•
Please observe the operating instructions for the connected
appliances.
•
If the power drawn by the connected appliances is above 150 W,
the inverter in the socket will get warm. The inverter will trip out if
the temperature exceeds a certain limit. The inverter can trip out on
hot days even when an appliance with a suitable power rating is
used. The inverter will switch on again automatically after it has
cooled down. Appliances which are already connected and
switched on will be activated again automatically ⇒.
•
Do not connect lamps which contain a neon tube. For technical
reasons, this may damage the lamp.
•
Do not connect 115 Volt appliances to the 230 Volt Euro socket.
This may cause irreparable damage to the appliance. Check the type
plate on the appliance if you are unsure of the voltage rating.
•
With some power supplies (e.g. on laptop computers), the inte-
grated surge suppressor prevents the equipment from being
switched on because the starting current is too high. If this
happens, please disconnect the power supply unit from the load
and wait for about 10 seconds before re-connecting.Note
•
Unshielded equipment can cause interference on the radio, TV
and vehicle's electrical system.
•
The Euro socket has an integrated child safety device. There is no
power at the socket until the Euro connector is fully inserted.
•
Some appliances may not function normally due to the lower
power rating (wattage).
•
The socket can be operated with 115 Volt power supplies, as is
the case in certain countries. In this case, a different type of inverter
must be installed in the vehicle. Retrofit kits are available from your
Audi dealer. Do not connect 115 Volt appliances to the 230 Volt Euro
socket.
•
Interference can occur on the radio's AM waveband if electrical
appliances are used near the rear window aerial.
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Intelligent technology199
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Note
To ensure that the ASR works properly, all four wheels must be fitted
with identical tyres. Any differences in the rolling radius of the tyres
can cause the system to reduce engine power when this is not
desired. Also refer to ⇒page 245, “Replacing wheels and tyres”.Electronic differential lock (EDL)
The electronic differential lock monitors the speed of the
driven wheels.General notes
The electronic differential lock (EDL) helps the car to start moving,
accelerate and climb a gradient in slippery conditions where this
may otherwise be difficult or even impossible.
How the system works
The EDL acts automatically. With the aid of the ABS sensors
⇒page 197, the system monitors the rotational speed of the driven
wheels on each axle. Whenever it detects a significant difference in
the speed of the driven wheels of one axle (for example, if the road is
slippery on one side) the system applies the brake to slow down the
spinning wheel so that more of the power is directed to the other
wheel of this axle (or to the three other wheels on vehicles with four-
wheel drive). This function is active up to about 100 km/h. The brake
system will make noises while it is working.
Driving away from a standstill
Sometimes one wheel has less grip and starts spinning, for
example, if one of the driven wheels is on ice. In this case, keep
pressing the accelerator gradually until the car starts moving, even
though the wheel with less grip will still spin.
Overheating of the brakes
To prevent the disc brake of the braked wheel from overheating, the
EDL cuts out automatically if subjected to excessive loads. The car remains operational and will behave in the same way as a car
without EDL.
The EDL will switch on again automatically when the brake has
cooled down.
WARNING
•
When accelerating on a uniformly slippery surface (for instance
all four wheels on ice or snow), press the accelerator gradually and
carefully. The driven wheels may otherwise start to spin (in spite
of the EDL), which would impair the car's stability and could lead
to an accident.
•
Even with EDL, you should always adjust your speed to suit the
conditions. Do not let the extra safety provided tempt you into
taking any risks when driving – this can cause accidents.Note
If the ABS warning lamp lights up, this can also mean there is a fault
in the EDL. Please contact a qualified workshop as soon as
possible.BrakesNew brake pads
New brake pads do not give full braking effect for the first 400 km,
they must first be “bedded in”. However, you can compensate for
the slightly reduced braking effect by applying more pressure on
the brake pedal. Avoid placing a heavy load on the brakes during the
running-in period.
We ar
The rate of wear on the brake pads depends a great deal on how you
drive and the conditions in which the vehicle is operated. Negative
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Intelligent technology 200factors are, for instance, city traffic, frequent short trips or hard
driving with abrupt starts and stops.
Wet roads; road salt
When you are driving at a speed higher than 80 km/h and have the
windscreen wipers switched on the brake pads are very briefly
brought into contact with the brake discs. This automatic process
which goes unnoticed by the driver is carried out at regular intervals
and is intended to improve braking response in wet conditions.
In certain conditions, such as in heavy rain, or after washing the car
or driving through water, the full braking effect can be delayed by
moisture (or in winter by ice) on the discs and brake pads. The
brakes should be “dried” by pressing the pedal to restore full
braking effect.
The effectiveness of the brakes can also be temporarily reduced if
the car is driven for some distance without using the brakes when
there is a lot of salt on the road in winter. The layer of salt that accu-
mulates on the discs and pads can be removed with a few cautious
brake applications.
Corrosion
There may be a tendency for dirt to build up on the brake pads and
corrosion to form on the discs if the car is used infrequently, or if
you only drive low mileages without using the brakes very much.
If the brakes are not used frequently, or if corrosion has formed on
the discs, it is advisable to clean off the pads and discs by braking
firmly a few times from a moderately high speed ⇒.
Faults in the brake system
If the brake pedal travel should ever increase suddenly, this may
mean that one of the two brake circuits has failed. Drive immedi-
ately to the nearest qualified workshop and have the fault rectified.
On the way to the dealer, be prepared to use more pressure on the
brake pedal and allow for longer stopping distances.Low brake fluid level
Malfunctions can occur in the brake system if the brake fluid level is
too low. The brake fluid level is monitored electronically.
Brake servo
The brake servo amplifies the pressure you apply to the brake pedal.
It only works when the engine is running.
WARNING
•
When applying the brakes to clean off deposits on the pads and
discs, select a clear, dry road. Be sure not to inconvenience or
endanger other road users; do not risk an accident.
•
Never let the car coast with the engine switched off (this can
cause accidents).Caution
•
Never let the brakes “drag” by leaving your foot on the pedal
when you do not really intend to brake. This overheats the brakes,
resulting in longer stopping distances and greater wear.
•
Before driving down a long, steep gradient, it is advisable to
reduce speed and move the selector lever to a lower gear. In this
way you will make use of the engine braking effect and relieve the
load on the brakes. If you still have to use the brakes, it is better to
brake firmly at intervals than to apply the brakes continuously.Note
•
If the brake servo is out of action due to a malfunction, or if the
car has to be towed, you will have to press the brake pedal consid-
erably harder to make up for the lack of servo assistance.
•
If you wish to equip the car with accessories such as a front
spoiler or wheel covers, it is important that the flow of air to the
front wheels is not obstructed, otherwise the brakes can overheat.
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Your vehicle and the environment205
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Your vehicle and the environmentRunning inA new vehicle should be run in over a distance of 1,500 km. For the
first 1,000 km the engine speed should not exceed 2/3 of the
maximum permissible engine speed – do not use full throttle and do
not tow a trailer or caravan. From 1,000 to 1,500 km you can gradu-
ally increase the engine rpm and road speed.
During its first few hours of running, the internal friction in the
engine is greater than later on when all the moving parts have
bedded down.
How the vehicle is driven for the first 1,500 km also influences the
engine quality. After the first 1,500 km you should continue driving
at moderate engine speeds, in particular when the engine is cold.
This helps to reduce wear and tear on the engine and increases the
potential mileage which can be covered by the engine.
You should also avoid driving with the engine speed too low.
Change down to a lower gear when the engine no longer runs
“smoothly”. Excessively high engine speeds are prevented by an
automatic rev limiter.Emission control systemsCatalytic converter
Applies to vehicles with petrol engine: The vehicle must only be
used with unleaded petrol, otherwise the catalytic converter will be
destroyed.
Never run the tank completely dry. The irregular fuel supply can
cause misfiring, which would allow unburnt fuel to enter the
exhaust system, which could cause overheating and damage the
catalytic converter.Diesel particulate filter
Applies to vehicles with diesel engine: The diesel particulate filter
can filter out almost all soot particles contained in the exhaust gas.
In normal driving conditions the filter is self-cleaning. Should the
self-cleaning function of the filter not be able to operate, e.g. when
the vehicle is continuously used only for short trips, the filter
becomes obstructed with soot and the symbol
 for the diesel
particulate filter lights up ⇒page 37.
WARNING
•
Because of the high temperatures which can occur in the emis-
sion control system (catalytic converter or diesel particulate
filter), do not park the vehicle where the exhaust can come into
contact with flammable materials under the car (e.g. on grass or
at the forest edge). - Fire hazard!
•
Do not apply any underseal agents in the area around the
exhaust system - fire hazard!
Driving abroadChanging over headlight dip settings
The asymmetric low beams of the headlights are designed to light
up the near side of the road more intensely. If you drive in a country
where traffic drives on the opposite side of the road to the home
country, this will dazzle oncoming traffic.
Headlights with halogen bulbs: To avoid dazzling oncoming traffic
you can apply opaque stickers to certain parts of the headlight
lenses.
Headlights with xenon gas-discharge bulbs*: The headlight dip
settings must be changed to avoid dazzling oncoming traffic. For
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