ECU AUDI A4 2008 B8 / 4.G Owner's Guide

Towing a trailer 240Applies to vehicles: with towing bracketTowing bracket (retrofitting)
If required, the vehicle can be retrofitted with a towing
bracket.If a towing bracket is to be fitted after the car is purchased, this must
be done according to the instructions of the towing bracket manu-
facturer.
The securing points, which are marked by an in the illustrations
⇒fig. 245 and ⇒fig. 246, are located under the vehicle.
Audi dealers are familiar with the method of installation and any
modifications which may be required for the cooling system.
WARNING
•
If a towing bracket is retrofitted, the installation should be
carried out by a qualified workshop.
•
If the towing bracket is incorrectly fitted, this could cause a
safety risk.
•
For your own safety, please observe the instructions provided
by the manufacturer of the towing bracket.Caution
If the connector socket is not fitted correctly, this could cause
damage to the vehicle's electrical system.
Fig. 245 Positions of
securing points (side
view)Fig. 246 Positions of
securing points (from
above)AA
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Checking and topping up fluids 256Closing 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. 252 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 () . . . . . . . . . . . . . . . . . . . . .
Jump-start terminal (-) with hexagon head . . . . . . . . .
Windscreen washer container (
) . . . . . . . . . . . . . . . .
Hydraulic fluid reservoir for power steering . . . . . . . .
A1
265, 294
A2
262
A3
259
A4
258
A5
261
A6
265, 294
A7
267
A8
225
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Checking and topping up fluids 266
– 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 256.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.
Replacing 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 226.
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 264, “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.
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Wheels and tyres 272replacement parts, trained personnel and facilities for disposing of
the old tyres.
WARNING
•
It is very important to ensure that the tyres you have chosen
have adequate clearance. When selecting replacement tyres, do
not rely entirely on the nominal tyre size marked on the tyre; with
some makes of tyre the effective tyre size can differ significantly
from the nominal dimensions, even though the tyres have the
same size designation. Inadequate tyre clearance can result in
damage to the tyres or the vehicle, causing a serious safety risk. It
may also invalidate the vehicle's type approval for use on public
roads.
•
Please ask your Audi dealer or qualified workshop whether run
flat tyres can be used on your vehicle. Unauthorised use of these
tyres can invalidate the vehicle's type approval for use on public
roads. Furthermore, this could cause damage to your vehicle and
possibly also result in an accident.
•
Avoid running the car on tyres that are more than 6 years old.
If you have no alternative, you should drive slowly and with extra
care at all times.For the sake of the environment
Old tyres must be disposed of according to the laws in the country
concerned.
Note
•
Never mount used tyres if you are not sure of their previous
history.
•
For technical reasons it is not normally possible to use wheel
rims from other vehicles. In some cases this also applies to rims
from other vehicles of the same model.
Wheel bolts
The wheel bolts are designed to suit the rims on your car.The wheel bolts are matched to the rims. When installing different
wheels (for instance wheels with winter tyres) it is important to use
the correct wheel bolts with the right length and correctly shaped
bolt heads. This is essential for the secure fit of the wheels and for
the proper function of the brake system.
Audi dealers have full information on the technical requirements
when installing or changing tyres, rims or wheel trims.
The wheel bolts should be clean and turn easily.
A special adapter is required to turn the anti-theft wheel bolts*
⇒page 292.Winter tyres
Winter tyres will significantly improve the car's handling
in winter road conditions.–Use only radial ply winter tyres.
– Winter tyres must be fitted on all four wheels.
– Only use winter tyres of the correct type approved for
your vehicle.
– Please note that the maximum permissible speed for
winter tyres may be lower than for summer tyres.
– Also note that winter tyres are no longer effective when
the tread is worn down.
– After fitting the wheels you must always check the tyre
pressures. The correct tyre pressures are listed on the
sticker on the end face of the driver's door.
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Self-help283
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Applies to vehicles: with fire extinguisherFire extinguisherThe factory-fitted fire extinguisher is located in the foot-
well on the front passenger's side (secured in a holder).Taking out the fire extinguisher
– Unfasten the retaining strap by pressing on the tab
marked “PRESS” ⇒fig. 266 -arrow-.
– Take the fire extinguisher out of the holder.
Securing the fire extinguisher
– Place the fire extinguisher in the holder.
– Secure the fire extinguisher with the retaining strap.
After using the fire extinguisher
– Have the fire extinguisher refilled and checked by a qual-
ified dealer or the fire service.Check how the fire extinguisher works before you need to use it. The
instructions for use are shown on the fire extinguisher.Have the fire extinguisher checked regularly (at least every two
years) by a qualified dealer or by the fire service to ensure that it will
be in working order when you need it.
When buying a new fire extinguisher, make sure it fits in the holder.
WARNING
If the fire extinguisher is not secured properly it could be cata-
pulted through the vehicle during driving and braking manoeuvres
or in the event of an accident. This poses a risk of injury to occu-
pants.
Note
•
The fire extinguisher must comply with legal requirements.
•
Observe the expiry date of the fire extinguisher. The fire extin-
guisher may not work properly after the expiry date.
Tools and Tyre Mobility SystemThe tools and the Tyre Mobility System are stored under
the floor panel in the luggage compartment.
Fig. 266 Fire extin-
guisher in footwell on
front passenger's side
Fig. 267 Luggage
compartment: Tools,
Tyre Mobility System
and jack
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Self-help 284If you need the tools, the Tyre Mobility System or the jack*, you will
have to open the floor panel and take out the spare wheel*
⇒page 284.
The tool kit includes:•
A hook for removing hub caps
•
Pin for mounting a wheel
•
Screwdriver with reversible blade
•
Tool for changing bulbs
•
Interchangeable socket (Torx socket for changing bulbs)
•
Crank handle for jack
•
Adapter for anti-theft wheel bolts*
•
Jack*
•
Box spanner for wheel bolts
•
Towline anchorage
Some of the parts listed are only fitted on certain models or are
optional extras.
Before stowing the jack* again, wind down the arm of the jack as far
as it will go.
WARNING
•
Do not use the hexagonal socket in the screwdriver handle to
tighten the wheel bolts. It is not possible to tighten the bolts with
the required torque – risk of accident.
•
The jack supplied by the factory is only designed for changing
wheels on this model. On no account attempt to use it for lifting
heavier vehicles or other loads – risk of injury.
•
Never start the engine when the vehicle is on the jack - risk of
accident.
•
If work has to be done under the veh i cl e , e n su re t h a t i t is sa fe l y
supported on stands designed for the purpose, otherwise there is
a risk of injury.
Applies to vehicles: with compact temporary spare wheelCompact temporary spare wheel*The spare wheel is carried in the wheel well under the
floor panel in the luggage compartment. It is only
intended for temporary use over short distances.Taking out the spare wheel
– Lift the floor panel by the plastic handle ⇒fig. 268.
– Hook the handle onto the luggage compartment weath-
erstrip.
– Turn the centre plastic knob ⇒fig. 268 anti-clockwise.
– Take out the spare wheel.
– Unhook the floor panel before closing the boot lid.
Securing the defective wheel in the spare wheel
well
– Place the wheel in the spare wheel well and secure it with
the plastic knob.
– Unhook the floor panel before closing the boot lid.
Fig. 268 Spare wheel
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Self-help289
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
–Loosen the wheel bolts ⇒page 289.
–Raise the car with the jack* ⇒page 290.
–Ta k e o f f the wheel with the flat tyre and then put on the
spare wheel* ⇒page 291.
–Lower the vehicle to the ground.
– Tighten the wheel bolts firmly i n d i a g o n a l s e qu e n c e w i t h
the box spanner ⇒page 289.
–Fit the hub cap back on.After changing a wheel
What you must do after changing a wheel.– Place the wheel with the defective tyre in the spare wheel
well and secure it.
– Put the tools and the jack* back in the luggage compart-
ment.
–The inflation pressure of the newly fitted spare tyre must
be checked as soon as possible.
–Have the tightening torque of the wheel bolts checked as
soon as possible with a torque wrench. The correct tight-
ening torque is 120 Nm.
– Have the flat tyre replaced as quickly as possible.
Note•
If you notice that the wheel bolts are corroded and difficult to
turn when changing a wheel, they must be replaced before having
the tightening torque checked.
•
In the interest of safety, drive at moderate speeds until the tight-
ening torque of the wheel bolts has been checked.
Hub caps
The hub caps must be removed for access to the wheel
bolts.Removing
– Insert the hook (provided in the vehicle's tool kit) in the
hole in the hub cap.
–Pull off the hub cap ⇒fig. 271.Loosening and tightening the wheel bolts
The wheel bolts must be loosened before raising the
vehicle.
Fig. 271 Changing a
wheel: Removing a hub
capFig. 272 Changing a
wheel: Loosening
wheel bolts
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Self-help291
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Now fit the crank handle onto the jack by inserting it
in the opening on the knob ⇒page 290, fig. 274. Turn the
crank handle clockwise or anti-clockwise to secure it in
place.
– Raise the vehicle by winding the crank handle until the
defective wheel is clear of the ground.Recesses at the front and rear of the door sills mark the jacking
points ⇒page 290, fig. 273. There is one jacking point for each
wheel. The distance from the jacking points to the wheel arches is
approximately 20 cm at the front and 40 cm at the rear. The jack may
only be applied at the seam of the jacking points shown.
An unstable surface under the jack may cause the vehicle to slip off
the jack. Always provide a firm base for the jack on the ground. If
necessary use a large, strong board or similar support. On a hard,
slippery surface (such as tiles) use a rubber mat or similar to prevent
the jack from slipping.
WARNING
•
Prevent the base of the jack from slipping – risk of injury.
•
The car can be damaged if the jack is not applied at the correct
jacking points. There is also a risk of injury since the jack can slip
off suddenly if it is not properly engaged.
Taking off the wheel and putting on the spare wheel
Step-by-step instructions for taking off the wheel and
putting on the spare wheel.Change the wheel as described below after loosening the
wheel bolts and raising the vehicle with the jack*.
Taking off the wheel
–Using the hexagonal socket in the screwdriver handle
(provided in the vehicle's tool kit) ⇒fig. 275, unscrew the
wheel bolt nearest to the top and place the bolt on a
clean surface.
AD
Fig. 275 Changing a
wheel: Hexagonal
socket in screwdriver
handle to turn the
wheel bolts after they
have been loosenedFig. 276 Changing a
wheel: Mounting pin in
wheel bolt hole nearest
to the top
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Fuses and bulbs307
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Take the screwdriver and the interchangeable Torx socket
out of the vehicle tool kit.
– Remove the screws ⇒page 306, fig. 288 that secure the
trim panel to the lock carrier and detach the trim panel.
– Slacken the two screws that secure the headlight to the
lock carrier and the two screws at the underside of the
headlight (the screws at the underside should not be
slackened more than five turns) ⇒page 306, fig. 289.
– Carefully pull the headlight forward about 60 mm.
– Release and unplug the electrical connector.
– Carefully take the headlight out towards the front (swivel
it slightly if necessary).
Installing
– Perform all of the above steps in reverse sequence.The headlight must be inserted in two guides (on the underside of
the headlight). This is the only way to ensure that the headlight is
installed in the correct position. To determine whether the headlight
is correctly installed, check that it is aligned flush with adjacent
body parts (such as the wing panel).
Do not interchange the securing screws.
Caution
Please take particular care not to damage or scratch the adjacent
parts of the body when removing or installing the headlights.
Removing bulb for main beam headlights– Remove the headlight ⇒page 306.
– Take off the rubber cap ⇒fig. 290 ⇒ in “Changing
bulbs” on page 304.
– Press the connector in the direction of the arrow
⇒fig. 291.
– Remove the connector together with the bulb from the
headlight housing.
– Disconnect the connector from the base of the bulb
⇒ in “Changing bulbs” on page 304.
Fig. 290 Headlight
unit: Rubber cap is
highlightedFig. 291 Bulb holder
for main beam head-
lights
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Fuses and bulbs 308Installing the bulb for the main beam headlights
When installing a bulb, the lug on the base of the bulb
must be inserted into the appropriate mounting on the
bulb housing.– Attach the new bulb to the connector ⇒ in “Changing
bulbs” on page 304.
– Insert the bulb carefully into the bulb housing. Start by
placing the base of the bulb directly behind one of the
retaining hooks so that the lug fits into the recess on the
bulb housing.– Press the connector in the direction of the arrow
⇒fig. 293 until the bulb engages.
– Check that the bulb is securely seated in the bulb
housing.
– Fit the rubber cap and install the headlight ⇒page 306.
– Check whether the new bulb is working.
– Have the headlight settings checked.
Note
Ensure that the rubber cap is seated correctly so that no water can
enter the unit.Removing bulb for dipped headlights
Fig. 292 Bulb with
connector: The lug on
the base of the bulb is
highlightedFig. 293 Fitting bulb
for main beam head-
lights
Fig. 294 Headlight
unit: Cover
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