ECU AUDI A4 AVANT 2008 Service Manual

/b, WARNING (continued )
• Never secure or attach any luggage or other items to the LATCH
lower anchorages or to the tether .
• If a tether or other strap is used to attach a child restraint to the
front passenger seat, make sure that it is not so tight , that it
causes the weight-sensing mat to measure more weight than is
actually on the seat.
• The heavier weight registered can make the system work as
though an adult we re on the seat and deploy the Advanced Airbag
when it must be suppressed causing serious or even fatal injury to
the child. •
Using tethers on rear-facing child restraint
systems
Currently, few rea r-facing chi ld restraint systems come with a tether.
Pl eas e read and heed the chi ld res traint sy stem man ufa cture r's
instruct ions careful ly to determ ine how to proper ly instal l the
teth er.
& WARNING
A child in a rearward -facing child safety seat installed on the front
passenger seat will be seriously injured and can be killed if the
front airbag inflates - even with an Advanced Airbag System.
• The inflating airbag
will hit the child safety seat or infant
carrier with great force and will smash the child safety seat and
child against the backrest, center arm rest , or door.
• A tight tether or other strap on a rearward -facing child restraint
attached to the front passenger seat can put too much pressure
on the weight-mat in the seat and register a heavier weight in the
Advanced Airbag System . The heavier weight registered can make
the system work as though an adult were on the seat and deploy
Safety first
Child Safety
/b, WARNING (continued )
the Advanced Airbag when it must be suppressed causing serious
or even fatal injury to the child.
• If you must install a rearward facing child safety seat on the
front passenger seat because of exceptional circumstances and
the PASSENGER AIR BAG OFF light does not come on and stay on ,
immediately install the rear -facing child safety seat in a rear
seating position and have the a irbag system inspected by your
Audi dealer . •
Securing the upper tether strap to the anchor
bracket
Fig . 198 T ether strap:
prope r routing and
mounting
Securing the child restraint tether strap to the
tether anchor
R el ease or deplo y the tethe r str ap o n the chil d restraint
acco rding to the c hild restr ain t m anu fac ture r's usa ge
inst ructions. ._
irechnical data

lllffl.___T_ r_a _il _e_ r_ t_o _vv_ i_ n """g"'- ---------------------------------------------------
Trailer towing
Driving with a trailer
General information
Your Audi was designed primarily for passenger transpor­
tation.
If you plan to tow a trailer, please remember t hat the add it ional load
wi ll affect durability, economy and performance.
Trailer towing not only p laces more stress on the veh icle, it a lso ca lls
for more concentration from the driver.
For th is reasons, always fo llow the operating and dr iving instruc ­
t ions provided and use common sense. •
Technical requirements
Trailer hit ch
Use a weight -carrying hitch conforming to the gross trailer weight.
The hitc h must be suitab le for your veh ic le and tra iler and must be
mounted securely on the vehicle's chassis at a technically sound
l ocation. Use only a tra iler hitch with removable bal l mount. A lways
check with the trai ler hitch manufacturer to make sure that you are
using t he correct hitch .
Do not use a bumper hit ch .
The hitch must be installed in such a way that it does not interfere
with the impact-absorb ing bumper system . No mod ifications
shou ld be made to the vehicle exhaust and brake systems. From
time to time, check that all hitch mount ing bo lts re main securely
fastened.
When you are not towing a trai ler, remove the trailer hit c h ball
mount. Th is prevents the hitch from causing damage s hou ld your
vehic le be struck from
behind ~& .
Tire pre ssure
When towing a trailer, inf late the tires of your vehic le to the cold tire
pressure listed under "Full load" on the s ticker on the right door­
jamb . Inflate trai ler tires to tra iler and tire manufacturers' specifica­
t ions.
Lights
T he head ligh t settings shou ld be checked with the trailer at tached
before driving off. Have the head lights adjusted as necessary so
t hat you can see t he road ahead bu t not bl ind oncom ing traffic.
Check to make sure both vehicle and trailer lights are working prop ­
e rly .
Engine cool ing sy stem
Towing a t railer makes the eng ine work ha rder. It is imp ortant tha t
the cooling system's performance stands up to the additiona l
strain. Make sure that the coo ling system has enoug h fluid.
Traile r br ake s
If your tra ile r i s eq uipped wi th a braki ng system, check to be s ure
that it conforms to al l regu lations .
T he tra iler hydraulic brake system must no t be direct ly connected to
the vehic le's hydrau lic brake system .
Safety chains
Be sure trailer safety chains are properly connected from the trai ler
t o the h itch on the vehicle. Leave enough s lack in t he chains to
permit turning corners. When you install safety chains, make sure
they will not drag on the road when you are driving.
T he chains shou ld cross under t he trailer tongue to prevent it from
dropping in case of separation from the hitch. _,,,

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Trailer lights
Trailer lights must meet all regulations. Be sure to check with your
authorized Audi dealer for correct wiring, switches and relays .
Mirrors
If you are unable to see the traffic behind you using the regular
outside mirrors, then you
must install extended mirrors. It is impor ­
tant that you
always have clear vision to the rear .
& WARNING
After removing the trailer hitch, do not store it in your vehicle. In
case of sudden braking, the hitch could fly forward and injure you
or your passengers. •
Operating instructions
Maximum trailer weight
A trailer for your vehicle is limited to a typical class 1 or class 2
trailer .
Trailer load distribution
Be sure the load in the trailer is held securely in place to guard
against shifting, be it forward, backward or sideways.
Never allow a passenger to ride in a trailer~ & in "Driving instruc­
tions".
Tire pressure
When towing a trailer, inflate the tires of your vehicle to the cold tire
pressure listed under "Full load" on the sticker on the right door­
jamb. Inflate trailer tires to trailer and tire manufacturers' specifica­
tions .
Controls and equip­
ment Safety first Vehicle operation Lights
The
headlight settings should be checked with the trailer attached
before driving off. Adjust as necessary so that you can see the road
ahead but not blind oncoming traffic.
Check proper working of vehicle and trailer lights .
Power Supply
The power supply to the trailer is disconnected when the ignition
key is removed.
Safety chains
Be sure trailer safety chains are properly connected from the trailer
to the hitch on the vehicle . Leave enough slack in the chains to
permit turning corners. When you install safety chains, make sure
they will not drag on the road when you are driving.
The chains should cross under the trailer tongue to prevent it from
dropping in case of separation from the hitch.•
Driving instructions
Driving with a trailer always requires extra care and
consideration.
To obtain the best possible handling of vehicle and trailer,
please note the following:
- Do not tow a loaded trailer when your car itself is not
loaded.
- Be especially careful when passing other vehicles.
- Observe speed limits.
- Do not drive at the maximum permissible speed.
- Always apply brakes early.
- Monitor the temperature gauge.
Vehicle care Do-it-yourself service Technical data

Checking and filling -
-----------------------------==--------=--
& WARNING (continued)
ment. Wait until no steam or coolant can be seen or heard before
carefully opening the hood.
•
Closing the engine hood
- Pull the hood down until the pressure from the strut is
reduced.
- Let the hood
drop down and latch in place. Do not try to
push
it shut; it may fail to engage =:>& .
& WARNING
A hood that is not completely latched could fly up and block your
view while driving.
• When you close the engine hood, check it to make sure the
safety catch has properly engaged. The hood should be flush with
the surrounding vehicle body parts.
• If you notice while driving that the hood is not secured prop­
erly, stop at once and close it. •
Working in the engine compartment
Be especially careful whenever you work in the engine
compartment.
Whenever you must perform any work in the engine compartment,
for example checking and filling different fluids, there is a risk of
injury, burns and accidents. To prevent personal injury always
observe the following WARNINGS . The engine compartment of any
vehicle is a hazardous area
=> & .
• I I • • I
& WARNING
To help avoid injury, before you check anything under the hood:
• Turn off the engine.
• Remove the ignition key .
• Apply the parking brake.
• Move selector lever of automatic transmission to
"P" (Park);
put manual transmission in Neutral.
• Always let the engine cool down. Hot components will burn
skin on contact.
• To reduce the risk of being burned, never open the hood if you
see or hear steam or coolant escaping from the engine compart­
ment. Wait until no steam or coolant can be seen or heard before
carefully opening the hood.
• Keep children away from the engine compartment.
• Never spill fluids on hot engine components. They can cause a
fire.
• Never touch the radiator fan. The auxiliary electric fan is
temperature controlled and can switch on suddenly.
• Never open the coolant reservoir cap when the engine is still
warm . The coolant system is pressurized and hot coolant could
spray out.
• Protect your face, hands and arm from steam or hot engine
coolant by placing a thick rag over the cap when you open the
coolant reservoir .
• If work on the fuel system or the electrical system is necessary: -Always disconnect the battery.
- Never smoke or work near heaters or open flames. Fluids in
the engine compartment could start a fire .
- Keep an approved fire extinguisher immediately available.
• To avoid electrical shock and personal injury while the engine
is running or being started, never touch:
- Ignition cables
.,_
Vehicle care

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Fig. 21 O Oil filler cap
location: 3.2 liter, V6-
engine
Before you check anything in the engine compartment,
always read and heed all
WARNINGS=> & in "Working in
the engine compartment" on
page 273.
-Turn off the engine.
Unscrew the cap
"t=:r. to the engine oil filling hole
=> page 278, fig. 209 or=> fig. 210.
-Carefully top off with the appropriate oil in 0.5 liter doses.
-Check the oil level again after two minutes=> page 277.
-Top off the oil again, if necessary.
-Screw the cap back on the filling hole and slide the oil
dipstick in as far as it will go.
& WARNING
• While topping off, the oil must not come in contact with hot
engine parts
-fire hazard!
& WARNING (continued)
• The oil filler cap must be properly secured to prevent oil from
being sprayed on the hot engine and exhaust system when the
engine is running
-fire hazard!
• If your skin has come in contact with the engine oil, you must
subsequently cleanse it thoroughly.
0 Note
• The oil level must not be above range @-danger of converter or
engine damage! Contact an authorized dealership to draw off oil, if
necessary.
• Audi does not recommend the use of oil additives. They may
damage the engine and adversely affect your New Vehicle Warranty.
ffi For the sake of the environment
• Under no circumstances can the oil come in contact with the
sewage network or the soil.
• Observe and follow legal regulations when disposing of empty
oil containers. •
Changing the engine oil
We recommend that have your oil changed by an autho ­
rized Audi dealer or a qualified service station.
Before you check anything in the engine compartment, always read
and heed all WARNINGS =>
& in "Working in the engine compart ­
ment" on
page 273.
The engine oil must be changed according to the intervals specified
in your Maintenance
& Warranty booklet. This is very important
because the lubricating properties of oil diminish gradually during
normal vehicle use.
.,.
Vehic le care irechnical data

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& W ARNING (continued )
• The driver is respon sible for the correct tire pre ssure s for all
tire s on the vehicle. The applicable pressure values are located on
a st icker on the driver 's side B-pillar or on the inside of the fuel
filler flap.
• Only when all tire s on the vehicle are filled to the correct pres­
sure , the tire pressure monitoring system * can work correctly .
• The use of incorrect tire pressure values can lead to accidents
or other damage. Therefore it is essential that the driver observe
the specified tire pressure values for the tires and the correct pres­
sures for the function of the tire pressure monitoring system*.
• Always inflate tires to the recommended and correct tire pres ­
sure before driving off.
• Driving with underinflated tires bend more , letting them get
too hot resulting in tread separation , sudden tire failure and loss
of control.
• Ex cessive speed and /overloading can cause heat build -up ,
sudden tire failure and loss of control .
• If the tire pressure is too low or too high, the tires will wear
prematurely and the vehicle will not handle well.
• If the tire is not flat and you do not have to change a wheel
immediately, drive at reduced speed to the nearest service station
to che ck the tire pressure and add air as required .
0 Note
Driving without valve stem caps can cause damage to the tire
valves. To preve nt th is, a lways make s ure th at f acto ry installed va lve
stem caps on al l whee ls are securely mounted on the va lve .
~ For the sake of the environment
Underinflated tires will a lso increase the fuel consumpt io n. •
Tires and vehicle load limits
There are limits to the amount of load or weight t hat any vehic le and
any tire can carry . A ve hicle that i s ove rloa ded will not handle well
and is more d iff icu lt to stop . Overload ing can not only lead to loss
o f vehi cle control, but can also damag e impor tan t p arts o f the
vehic le and can lead to sudden tire failure, including a blowout and
sudde n defla tion that ca n cause the veh ic le to c ra sh .
Your sa fety a nd t hat o f your passe ngers a lso depe nds o n maki ng
s u re that load li mits are not exceeded. Vehic le load incl udes every ­
b ody and everythi ng i n and on t he vehicle . T he se l oa d limi ts are
technical ly referred to as the ve hic le's
Gross Vehicle Weight Rating
("GVW R"l.
T he "GVWR" includes the wei ght of the basic vehic le, all factory
in sta lled acces so ries, a full t an k of f uel, o il, c oolant a nd oth e r flu ids
p lus max imum load . T he maximum load inc ludes th e number o f
p asse ngers tha t th e ve hicle i s intended t o carry ("seat ing ca paci ty")
with an assu med weight o f 150 l bs (68 kg) fo r each passe nger at a
designated seating position and the total weight of any luggage in
th e v ehic le. I f you tow a trai ler, the we ig ht o f the tra iler hitch a nd th e
tongue weight of the loaded trailer must be inc luded as part of the
ve hicle lo ad .
The
Gross Axle Weight Rating ("GAWR") is t he maximum load that
ca n b e app lie d at eac h of th e veh icle's two axle s.
T he G ross Ve hicle We ight Rati ng a nd th e G ross A xle Wei ght R ati ng
are listed on the safety comp liance stic ker label located either on
t he driver 's si de B-pi lla r o r on the in sid e of t he fue l fille r fl ap. You r
Aud i has 5 seating posit ions, 2 in the front and 3 in the rear for total
sea ting ca paci ty of 5. Each sea ting p osit ion has a safe ty b elt
=> page 176, "Saf ety be lts" .
The fact that there is an upper limit to your vehicle's Gro ss Vehicle
W eight Rat ing m eans that th e total weight o f whatever is b ein g
carried in the vehic le (including the weight of a traile r hitc h and the
ton gue we ight of the loaded tr aile r) is lim it e d. Th e m or e passe ng ers
~
Vehicle care

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W up to 168 mph (270 km/h)3
)
Y up to 186 mph (298 km/h)3
l
Your vehicle is normally factory equipped tires, which possess
excellent driving characteristics and give your Audi optimum
driving comfort. An electronic speed
limiter => page 28will normally
prevent your vehicle from going faster than the tire speed rating
=> & .
U .S. DOT Tire Identification Number (TIN) and tire
manufacture date
This is the tire's "serial number". It begins with the letters "DOT"
and indicates that the tire meets all federal standards. The next two
numbers or letters indicate the plant where it was manufactured,
and the last four numbers represent the week and year of manufac­
ture . For example, the numbers 2205 mean that the tire was
produced in the 22th week of 2005. The other numbers are
marketing codes that may or may not be used by the tire manufac­
turer. This information is used to contact consumers if a tire defect
requires a recall.
Tire ply composition and materials used
The number of plies indicates the number of layers of rubber-coated
fabric in the tire. In general, the greater the number of plies, the
more weight a tire can support. Tire manufacturers also must indi­
cate the materials in the tire, which include steel, nylon, polyester,
and others.
Maximum Load Rating
This number indicates the maximum load in kilograms and pounds
that can be carried by the tire.
Tire quality grading for treadwear, traction, and
temperature resistance
Tread wear, traction and temperature grades=> page 309 . Maximum Permissible Inflation Pressure
This number is
the greatest amount of air pressure that should ever
be put in the tire under normal driving conditions.
Replacing tires or rims on vehicles equipped with tire
pressure monitoring system*
The wheels on your vehicle are equipped with a sensor which
constantly monitors the air pressure inside the tire, and then trans­
mits this information to the tire pressure monitoring system*. If you
are going to replace the wheel rims on your vehicle, make sure the
new rims also have these sensors. The sensors must be compatible
with the tire pressure monitoring system* on your vehicle.
If you install rims, which do not have the sensors, or have sensors
which are not compatible, then the tire pressure monitoring
system * will not work properly. In this case, the tire pressure moni­
toring system* would not be able to monitor the tire pressure or
warn you if it is necessary .
• The battery inside of the tire pressure sensor has a limited
service life.
• Always drive with the valve stem caps securely mounted. We
recommend using factory installed valve stem caps . Ask your autho­
rized Audi dealer to replace lost valve stem caps.
The installation of replacement tires with steel cord body plies in
the tire sidewall may cause malfunction of the tire pressure moni­
toring system, and is not recommended (cord material information
in molded on the tire sidewall).
Always check your tire pressure monitoring system* indicator after
replacing one or more tires on your vehicle. If the tire pressure
monitoring system * indicator flashes, or is on, your system is not
working properly. Your replacement tire might be incompatible with
your tire pressure monitoring system*, or some component of the
tire pressure monitoring system* may be damaged.
....
Vehicle care

Tires and wheels 1111
----------------
W For the sake of the environment
Use summer tires when weather conditions permit. They are
quieter, do not wear as quickly and reduce fuel consumption. •
Snow chains
Snow chains may be fitted only to the front wheels, and only to
certain tire sizes. Ask your authorized Audi dealer on which tire
sizes snow chains can be used.
If you are going to use snow chains, then you must install them on
the front wheels at least.
The snow chains must have low-profile links and must not be thicker
than 0.53 inch (13.5 mm), including the lock.
Remove wheel center covers and trim discs before putting snow
chains on your
vehicle => 0. For safety reasons cover caps must
then be fitted over the wheel bolts. These are available from autho­
rized Audi dealers.
& WARNING
Using the wrong snow chains for your vehicle or installing them
incorrectly can increase the risk of loss of control leading to
serious personal injury.
• Snow chains are available in different sizes. Always make sure
to follow the instructions provided by the snow chain manufac­
turer.
• When driving with snow chains never drive faster than the
speed permitted for your specific snow chains.
• Always observe local regulations .
0 Note
• Remove snow chains before driving on roads not covered with
snow to avoid damaging tires and wearing the snow chains down
u n necessarily.
• Snow chains, which come into direct contact with the wheel rim,
can scratch or damage it . Therefore, make sure that the snow chains
are suitably covered.
[ i] Tips
Where snow chains are mandatory on certain roads, this normally
also applies to vehicles with All Wheel Drive. •
Wheel bolts
Wheel bolts must always be tightened to the correct
torque.
The design of wheel bolts is matched to the factory installed rims. If
different rims are fitted, the correct wheel bolts with the right length
and correctly shaped bolt heads must be used. This ensures that
wheels are fitted securely and that the brake system functions
correctly.
In certain circumstances, you may not use wheel bolts from a
different vehicle -even if it is the same
model => page 348.
& WARNING
Improperly tightened or maintained wheel bolts can become loose
causing loss of control, a collision and serious personal injury.
• Always keep the wheel bolts and the threads in the wheel hubs
clean so the wheel bolts can turn easily and be properly tightened .
• Never grease or oil the wheel bolts and the threads in the wheel
hubs. They can become loose while driving if greased or oiled,
even if tightened to the specified torque.
.,_
Vehicle care

lllffll....__W_ h_ a_ t_d_ o_ l _d _o_ n_ o_ vv_ ? ______________________________________________ _
What do I do now?
Jack, tools and spare wheel
Jack and tools
The tools and jack are stored underneath the floor panel
in the luggage compartment.
F ig. 222 Tool case and
ve hicle jack
Fi g. 223 O pen too l
case
The tool case @ and the vehicle jack@ are stored under­
neath the floor panel in the luggage compartment
=> fig. 222.
- For access, raise t he floor panel at the plastic ha ndle @ .
- Securely engage the handle in the luggage compartment
seal as illustrated to keep the floor panel up.
- Take out tool case and/or jack.
- Disengage and lower the floor panel before you close the
luggage compartment lid again.
The onboard tool kit inc ludes:
• Hook for removing wheel covers*
• Plastic hook to remove wheel bolt covers
• Wheel bo lt wrench
• Alignment pin for changing wheels
• Screwdriver with reversible blade
• Towing eye
Before storing the jack, make sure it is wound back down as far as it
will go.
Afte r use, th e ja c k a nd tools m us t b e put bac k in pl ace u nderneath
th e floor p an el in th e lu g gage c omp artment .
Note: some of the on -board items listed above are provided on
certain models only or are optional extras.
& WARNING
Improper us e of th e vehi cle ja ck ca n ca use se rious pe rso nal inju ­
r ies.

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/b, WARNING (continued)
• Using a bumper jack to raise the vehicle will damage the
bumper system. The jack may slip, causing injury.
• Never support your vehicle on cinder blocks, bricks or other
objects. These may not be able to support the load and could
cause injury when they fail.
• Never start or run the engine while the vehicle is supported by
the jack.
• If you must work under the vehicle, always use safety stands
specifically designed for this purpose.
• Never try and use the hexagonal socket
in the handle of the
screwdriver to loosen or tighten the wheel bolts.
• Always make sure the spare tire and even a flat tire are secured
in place and not loose, otherwise they could fly forward, causing
personal injury to passengers in the vehicle in an accident or
sudden maneuver.
• Never use the jack supplied with your Audi on another vehicle,
particularly on a heavier one. The jack is only suitable for use on
the vehicle it came with.
•
Spare wheel
The spare wheel is stored in the wheel well underneath
the floor panel in the luggage compartment.
Fig. 224 Luggage
compartment : spare
wheel
Your vehicle is equipped with a regular spare wheel. It is
held in place by an oversize screw.
Taking out the spare wheel
- Raise the floor panel at the plastic handle.
- Securely engage the handle in the luggage compartment
seal as illustrated to keep the floor panel up.
- Unscrew the knurled retainer bolt in the wheel center
=> fig. 224. Turn it counter -clockwise .
- Take out the spare wheel.
- Disengage and lower the floor panel before you close the
luggage compartment lid again.
..,.
Do-it-yourse lf service irechnical data