2008 AUDI A5 check engine light

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 fluids 238Brake fluidChecking brake fluid level
The brake fluid level can be checked at a glance.– Check the fluid level on the brake fluid reservoir
⇒fig. 228. It should always be between the “MIN” and
“MAX” marks.In right-hand drive vehicles the brake fluid reservoir is on the other
side of the engine compartment.
The fluid level may drop slightly after a period of time due to the
automatic compensation for brake pad wear. This is quite normal.
However, if the level goes down noticeably in a short time, or drops
below the “MIN” mark, there may be a leak in the brake system. If
the fluid level in the reservoir is too low, this will be indicated by the
brake warning lamp ⇒page 31. If this should happen, take the car
to a qualified workshop immediately and have the brake system
inspected.
Changing brake fluid
When required, the brake fluid should be changed by a
competent mechanic with the proper equipment.Brake fluid gradually absorbs moisture from the atmosphere. If the
water content in the brake fluid is too high, this may cause corrosion
in the brake system over time. In addition, the boiling point of the
brake fluid will be considerably reduced. This could adversely affect
the braking ability in certain circumstances.
For this reason the brake fluid must be changed periodically.
Your vehicle's Service Schedule will tell you when the brake fluid has
to be changed.
It is advisable to have the brake fluid changed as part of a regular
Inspection Service at your Audi workshop. They are familiar with the
procedure and have the necessary special tools and spare parts as
well as the proper facilities for disposing of the old fluid.
Use only the genuine brake fluid specified by the factory Qualified
workshops know that the brake fluid “DOT 4” is approved by Audi.
The brake fluid must be fresh and unused.
WARNING
•
Brake fluid is poisonous; store it in the sealed original container
in a safe place out of reach of children.
•
Heavy use of the brakes may cause a vapour lock if the brake
fluid is left in the system for too long. This would seriously affect
the efficiency of the brakes and the safety of the car – risk of acci-
dent.Caution
Please note that brake fluid will attack the paintwork on contact.
Fig. 228 Engine
compartment: Mark-
ings on brake fluid
reservoir
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Checking and topping up fluids 240Important safety warnings for handling a car battery
All work on batteries requires specialist knowledge.The vehicle battery is located under the floor panel in the luggage
compartment.
WARNING
Always be aware of the danger of injury and chemical burns as
well as the risk of accident or fire when working on the battery and
the electrical system.•
Wear safety glasses. Do not allow acid or lead particles to come
into contact with eyes, skin or clothing.
•
Battery acid is extremely corrosive. Wear protective gloves and
safety glasses. Do not tilt the battery - acid can leak out of the
vapour vent. If electrolyte should splash into the eyes rinse at once
for several minutes using clear water. Then seek medical care
immediately. Neutralize any acid splashes on the skin or clothing
with soap solution, and rinse off with plenty of water. If acid is
swallowed by mistake, consult a doctor immediately.
•
Keep open flames, sparks, uncovered lights and lit cigarettes
away from battery. Avoid sparks (including those from static charges) when handling cables and electrical equipment. Never
cross the battery poles. The resulting high-energy sparks can
cause injury.
•
A highly explosive mixture of gases is given off when the
battery is under charge. Only charge battery in a well ventilated
area.
•
Keep children away from the battery and battery acid.
•
Switch off all electrical equipment before starting any work on
the vehicle electrical system. Remove the ignition key. The minus
cable of the battery must be disconnected. When changing a light
bulb, it is sufficient to only turn off the light.
•
Before disconnecting the battery, turn off the anti-theft
system! Otherwise, the alarm will sound.
•
When disconnecting the battery from the vehicle's electrical
system, first disconnect the minus cable and then the plus cable.
•
Before reconnecting the battery, turn off all electrical equip-
ment. First connect the plus cable, then the minus cable. The
battery cables must not be connected to the wrong battery poles
- serious risk of cable fire.
•
Never charge a frozen or thawed out battery - risk of explosion
and chemical burns! A battery must be replaced once it has been
frozen. When it is discharged the battery can freeze at tempera-
tures around 0°C.
•
Make sure that the vapour hose is always attached to the
battery.
•
Never use a damaged battery - risk of explosion! Replace a
damaged battery immediately.Caution
•
Never disconnect the car's battery with the engine running or
with the ignition turned on, otherwise the electrical system or elec-
trical components will be damaged.

Wear safety glasses!

Battery acid is extremely corrosive. Wear protec-
tive gloves and safety glasses.

Keep open flames, sparks, uncovered lights and
lit cigarettes away from battery!

A highly explosive mixture of gases is given off
when the battery is under charge!

Keep children away from the battery and battery
acid.
WARNING (continued)
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Checking and topping up fluids241
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
Do not expose the battery to direct sunlight over a long period of
time, as the intense ultraviolet radiation can affect the battery
housing.
•
If the car is left standing for long periods, protect the battery
from extreme cold temperature so that it does not “freeze up” and
become damaged.
Charging the battery
Terminals for charging the battery are fitted in the engine
compartment.– Note the warnings ⇒ in “Important safety warnings
for handling a car battery” on page 240 and ⇒.
– Switch off all electrical equipment. Remove the ignition
key.
– Open the bonnet ⇒page 230.
– Open the red cap on the positive terminal ⇒fig. 229.
– Follow the correct procedure for connecting the charger
cables to the jump-start terminals (terminal with red cap
= “positive”, terminal with hexagon = “negative”).– Now connect the battery charger to the mains and switch
on.
– After charging the battery: switch off the battery charger
and disconnect the mains cable.
– Now disconnect the charger cables.
– Refit the red cap onto the positive terminal.
– Close the bonnet ⇒page 232.
When it is discharged the battery can freeze at temperatures
around 0°C. A frozen battery must be thawed before charging ⇒.
However, it is advisable to replace the battery if it has frozen,
because the ice can crack the battery casing and allow the battery
acid to escape.
Charging the battery
Important: Before you charge the battery make sure you read the
manufacturer's instructions for using the battery charger.
When charging with a low current (for instance with a small battery
charger) the battery does not have to be disconnected. The battery
must not be opened while you are charging it.
Fast-charging the battery
For technical reasons it is not permissible to fast-charge the battery
using charging devices with an output voltage higher than 14.8 V.
WARNING
Never charge a frozen battery – it could explode.
Note
Use only the terminals in the engine compartment to charge the
battery.
Fig. 229 Engine
compartment: Termi-
nals for jump leads and
battery charger
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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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Fuses and bulbs277
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
WARNING
•
Take particular care when working on components in the
engine compartment if the engine is warm - risk of burns!
•
Bulbs are sensitive to pressure. The glass can break when you
touch the bulb, causing injury.
•
Incorrect handling of the high-voltage element of xenon gas-
discharge bulbs* can have potentially fatal consequences.
•
When changing bulbs, please take care not to injure yourself on
sharp edges, in particular on the headlight housing.Caution
•
Always remove the ignition key before carrying out any work on
the electrical system - danger of short circuiting!
•
Switch off the lights or parking lights before you change a bulb.
•
Take good care to avoid damaging any components.
•
Removing the lights in particular can lead to the paintwork
becoming damaged. This is another reason why we recommend
having the bulbs changed by a qualified workshop.For the sake of the environment
Please ask your specialist retailer how to dispose of used bulbs in
the proper manner.
Note
Place the parts you have removed on a soft cloth so that they do not
become scratched.
•
Please check at regular intervals that all lighting (especially the
exterior lighting) on your vehicle is functioning properly. This is not
only in the interest of your own safety, but also in that of all other
road users.
•
Before changing a bulb, make sure you have the correct new
bulb.
•
Do not touch the glass part of the bulb with your bare hands, use
a cloth or paper towel instead. Otherwise, the fingerprints left on
the glass will vaporise as a result of the heat generated by the bulb,
be deposited on the reflector and impair its surface.
Bulbs with a bayonet fastenerBulbs with a bayonet fastener must be changed as follows:
Removing the bulb
– Lightly press the defective bulb into the bulb holder, then
turn it anti-clockwise and remove it.
– Do not touch the glass part of the new bulb with your
bare hands, use a cloth or paper towel instead.
Fitting the bulb
– Fit the new bulb, pressing it into the bulb holder, and turn
it clockwise as far as it will go.
– If necessary, use a cloth to remove any fingerprints from
the glass part of the bulb.
Reversing lights
W 16 W
Rear fog light
H 21 W
Number plate lights
5 W
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Index 302AABS
SeeAnti-lock brake system . . . . . . . . . 18
AC mode . . . . . . . . . . . . . . . . . . . . . . . 98, 107
Acceleration figures
SeePerformance, weights and
dimensions . . . . . . . . . . . . . . . . . . . . 295
Accessories . . . . . . . . . . . . . . . . . . . . . . . . 250
Trailer . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Adapter for anti-theft wheel bolts . . . . . 264
adaptive light . . . . . . . . . . . . . . . . . . . . . . . 58
Defective . . . . . . . . . . . . . . . . . . . . . . . . 37
advanced key
Locking and unlocking the vehicle . . . 45
START ENGINE STOP button . . . . . . . 118
Starting the engine . . . . . . . . . . . . . . . 118
Switching on the ignition . . . . . . . . . . 118
Air conditioner . . . . . . . . . . . . . . . . . . 93, 101
AC mode . . . . . . . . . . . . . . . . . . . . . . . . . 98
See alsoDeluxe automatic air conditioner
93
Air recirculation mode
Deluxe automatic air conditioner . . . . 97
Deluxe automatic air conditioner plus . . .
106
Airbag . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Deactivating . . . . . . . . . . . . . . . . . . . . . 183
Front airbags . . . . . . . . . . . . . . . . . . . . 178
Head-protection airbag . . . . . . . . . . . 181
Key-operated switch for front passenger's
airbag . . . . . . . . . . . . . . . . . . . . . . . . 183
Side airbags . . . . . . . . . . . . . . . . . . . . . 180Triggering . . . . . . . . . . . . . . . . . . . . . . 177
Warning lamp . . . . . . . . . . . . . . . . . . . . 16
Alterations to the vehicle . . . . . . . . . . . . . 250
Alternator
Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Anti-dazzle interior mirror . . . . . . . . . . . . . 66
Anti-freeze additive . . . . . . . . . . . . . . . . . 235
Anti-knock properties of petrol . . . . . . . . 227
Anti-lock brake system
How the system works . . . . . . . . . . . . 197
Warning lamp . . . . . . . . . . . . . . . . . . . . 18
Anti-theft alarm . . . . . . . . . . . . . . . . . . . . . . 42
Interior monitor . . . . . . . . . . . . . . . . . . . 47
Tow-away protection . . . . . . . . . . . . . . 47
Anti-theft wheel bolts . . . . . . . . . . . . . . . . 264
Armrest (front)
Adjusting . . . . . . . . . . . . . . . . . . . . . . . . 77
Storage compartment . . . . . . . . . . . . . 77
Ashtrays
Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Audi hold assist . . . . . . . . . . . . . . . . . . . . 124
Warning lamp . . . . . . . . . . . . . . . . . . . . 18
Auto Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Auto-check control . . . . . . . . . . . . . . . . . . . 29
Automatic air conditioner plus
SeeDeluxe automatic air conditioner plus
101
Automatic gearbox
Manual release (multitronic®) . . . . . . 136
multitronic® . . . . . . . . . . . . . . . . . . . . 130
Safety interlock for ignition key . . . . 116Selector lever positions (multitronic®) . . .
131
Steering wheel with tiptronic controls . . .
135
Automatic headlight control . . . . . . . . . . . 54
Auxiliary heating
Deluxe automatic air conditioner plus . . .
111
Description . . . . . . . . . . . . . . . . . . . . . . 111
Remote control . . . . . . . . . . . . . . . . . . 114
Running time . . . . . . . . . . . . . . . . . . . . 113
Switching on/off immediately . . . . . . 112
Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Average fuel consumption . . . . . . . . . . . . . 25
Average speed . . . . . . . . . . . . . . . . . . . . . . . 25
Axle weights
SeePerformance, weights and
dimensions . . . . . . . . . . . . . . . . . . . . 295
BBattery
Charging . . . . . . . . . . . . . . . . . . . . . . . . 241
Low charge . . . . . . . . . . . . . . . . . . . . . . 202
Power level . . . . . . . . . . . . . . . . . . . . . . 202
Power management . . . . . . . . . . . . . . 202
Replacing . . . . . . . . . . . . . . . . . . . . . . . 242
Winter conditions . . . . . . . . . . . . . . . . 239
Battery power . . . . . . . . . . . . . . . . . . . . . . . 36
Bayonet fastener
Bulb . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Bulb holder . . . . . . . . . . . . . . . . . . . . . . 278
Belt tensioners . . . . . . . . . . . . . . . . . . . . . 175
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Index 304Convenience open function . . . . . . . . . . . 50
Cooling system
Anti-freeze additive . . . . . . . . . . . . . . . 235
Checking coolant level . . . . . . . . . . . . 236
Coolant . . . . . . . . . . . . . . . . . . . . . . . . . 235
Coolant temperature gauge . . . . . . . . . 11
Malfunction . . . . . . . . . . . . . . . . . . . . . . 32
Radiator fan . . . . . . . . . . . . . . . . . . . . . 237
Topping up coolant . . . . . . . . . . . . . . 236
Cruise control system
Adjusting speed . . . . . . . . . . . . . . . . . 127
Control lever on steering wheel . . . . 125
Cruise mode . . . . . . . . . . . . . . . . . . . . 126
Indicator lamp . . . . . . . . . . . . . . . . . . . . 17
Introduction . . . . . . . . . . . . . . . . . . . . . 125
Pre-selecting a speed . . . . . . . . . . . . . 128
Resuming cruise control . . . . . . . . . . 128
Safety notes . . . . . . . . . . . . . . . . . . . . . 125
Switching off . . . . . . . . . . . . . . . . . . . . 129
Switching off temporarily . . . . . . . . . 128
Cup holders . . . . . . . . . . . . . . . . . . . . . . . . . 85
Current fuel consumption . . . . . . . . . . . . . 25DDate display . . . . . . . . . . . . . . . . . . . . . . . . 13
Daytime running lights . . . . . . . . . . . . . . . 56
DCP
SeeDynamic gear control program . 133
Deactivating front passenger's airbag . . 183
Deadlock mechanism . . . . . . . . . . . . . . 43, 46
Defrosting windows . . . . . . . . . . . . . . 98, 107Deluxe automatic air conditioner . . . . . . . 93
Air distribution . . . . . . . . . . . . . . . . . . . 97
Air outlets . . . . . . . . . . . . . . . . . . . . . . . . 99
Air outlets for rear passengers . . . . . . 99
Air recirculation mode . . . . . . . . . . . . . 97
Automatic mode . . . . . . . . . . . . . . . . . . 95
Basic settings . . . . . . . . . . . . . . . . . . . 100
Blower . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Controls . . . . . . . . . . . . . . . . . . . . . . . . . 94
Defrosting . . . . . . . . . . . . . . . . . . . . . . . 98
Description . . . . . . . . . . . . . . . . . . . . . . . 93
Economical operation . . . . . . . . . . . . . 100
Heated rear window . . . . . . . . . . . . . . . 98
Seat heating, front . . . . . . . . . . . . . . . 115
Supplementary heater . . . . . . . . . . . . 101
Switching on and off . . . . . . . . . . . . . . 95
Temperature . . . . . . . . . . . . . . . . . . . . . 96
Deluxe automatic air conditioner plus . . 101
AC mode . . . . . . . . . . . . . . . . . . . . . . . . 107
Air distribution . . . . . . . . . . . . . . . . . . 106
Air outlets . . . . . . . . . . . . . . . . . . . . . . . 108
Air outlets for rear passengers . . . . . 108
Air recirculation mode . . . . . . . . . . . . 106
Automatic mode . . . . . . . . . . . . . . . . . 104
Automatic recirculation . . . . . . . . . . . 110
Auxiliary heating . . . . . . . . . . . . . . . . . 111
Auxiliary heating - remote control . . 114
Auxiliary heating - running time . . . . 113
Basic settings . . . . . . . . . . . . . . . . . . . 109
Blower . . . . . . . . . . . . . . . . . . . . . . . . . 105
Controls . . . . . . . . . . . . . . . . . . . . . . . . 103
Defrosting . . . . . . . . . . . . . . . . . . . . . . 107
Description . . . . . . . . . . . . . . . . . . . . . . 101
Economical operation . . . . . . . . . . . . . 109Heated rear window . . . . . . . . . . . . . . 107
Supplementary heater . . . . . . . . . . . . 110
Switching on and off . . . . . . . . . . . . . . 104
Synchronisation . . . . . . . . . . . . . . . . . 110
Temperature . . . . . . . . . . . . . . . . . . . . 104
Diesel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Diesel particulate filter . . . . . . . . . . . . 37, 205
Engine oil . . . . . . . . . . . . . . . . . . . . . . . 233
Digital clock . . . . . . . . . . . . . . . . . . . . . . . . . 13
Digital compass . . . . . . . . . . . . . . . . . . . . . 68
Digital speedometer . . . . . . . . . . . . . . . . . . 22
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 292
Dipped headlights . . . . . . . . . . . . . . . . . . . 54
Defective . . . . . . . . . . . . . . . . . . . . . . . . . 36
DIS
SeeDriver information system . . . . . . 20
Door catches/boot lid warning . . . . . . . . . 23
Doors
Manual locking . . . . . . . . . . . . . . . . . . . 48
Driver
SeeSitting position . . . . . . . . . . . . . . . 164
Driver information system . . . . . . . . . . . . . 20
Auto-check control . . . . . . . . . . . . . . . . 29
Bulb monitor . . . . . . . . . . . . . . . . . . . . . 36
CD and radio display . . . . . . . . . . . . . . . 21
Digital speedometer . . . . . . . . . . . . . . . 22
Door catches/boot lid warning . . . . . . 23
Driver messages . . . . . . . . . . . . . . . . . . 30
On-board computer . . . . . . . . . . . . . . . . 25
Outside temperature display . . . . . . . . 21
Red symbols . . . . . . . . . . . . . . . . . . . . . 30
Service interval display . . . . . . . . . . . . . 23
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