2008 AUDI A4 lock

Towing a trailer237
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Also check the shaft section of the ball joint and its asso-
ciated mechanical parts to make sure they are clean and
undamaged.Continued ⇒page 237, “Fitting the ball joint (step 2)”.
WARNING
It is important to keep the mounting fixture clean. Otherwise the
ball joint may fail to engage securely (accident risk).Applies to vehicles: with removable towing bracketFitting the ball joint (step 2)The spring mechanism inside the ball joint must
be in the "ready" position.
– Check that the red marking ⇒fig. 238 on the knob is
inside the green zone on the ball joint.
– Check that the locking ball is inside the hole in the
shaft section of the ball joint.
– Check that the knob protrudes visibly from the ball joint,
so that there is a clear gap between the knob and the
ball joint.
The ball joint can only be installed if the internal spring mechanism
is in the ready position.
Continued ⇒page 237, “Fitting the ball joint (step 3)”.Applies to vehicles: with removable towing bracketFitting the ball joint (step 3)Setting the spring mechanism to the "ready"
position (if required)
– Insert the key ⇒fig. 239 for locking the ball joint into
the lock on the knob and turn it clockwise.
Fig. 238 Removable
towing bracket: Ball
joint
A2A1A3
Fig. 239 Removable
towing bracket:
Setting the spring
mechanism to the
"ready" positionFig. 240 Removable
towing bracket:
Inserting the ball joint
A4
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Towing a trailer 238
– Pull out the knob in direction , hold and turn in direc-
tion until the locking ball engages ⇒.
Inserting the ball joint
– With the spring mechanism in the “ready” position,
insert the ball joint into the mounting fixture and push it
upwards ⇒page 237, fig. 240 in the direction indicated
(arrow) ⇒. The spring mechanism should then
engage automatically with an audible click.
– Lock the ball joint by turning the key anti-clockwise.
– Take out the key and press the cover cap provided onto
the lock.Continued ⇒page 238, “Fitting the ball joint (step 4)”.
WARNING
•
If it is not possible to set the spring mechanism to the "ready"
position as described above, do not use the ball joint. Please take
your vehicle to a qualified workshop.
•
To avoid injury, keep your hands away from the knob and the
cover piece when inserting the ball joint into the mounting fixture.Note
Make sure that the knob can turn freely when the ball joint is
inserted.
Applies to vehicles: with removable towing bracketFitting the ball joint (step 4)Safety check
– Check that the green marking ⇒fig. 241 on the knob
is inside the green zone on the ball joint.
– Check that the knob is directly against the ball joint, so
that there is no gap between the knob and the ball
joint.
– Check that the ball joint is locked and the key is removed
(so that the knob cannot be pulled out).
Aa
Ab
A5
Fig. 241 Removable
towing bracket: Safety
checkFig. 242 Area below
rear bumper: Electrical
socket for trailer
A6
A7
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Towing a trailer239
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– Check that the ball joint fits tightly in the mounting
fixture (try moving it about to check).
Electrical socket for trailer
– The cable of the towing bracket can be connected to the
socket ⇒page 238, fig. 242.If the safety check is not satisfactory, the ball joint must be fitted
again properly.
WARNING
To avoid accidents, the ball joint must meet all the safety require-
ments listed in the safety check. The towing bracket must not be
used if any one of these requirements is not met. If this is the case,
you should contact a qualified workshop.Applies to vehicles: with removable towing bracketRemoving the ball joint
– Take off the cover cap and insert the key ⇒fig. 243 in
the lock on the knob.
– Unlock the ball joint by turning the key clockwise.
– Take hold of the ball joint and pull out the knob in direc-
tion .
– Keep hold of the knob and turn it as far as it will go in
direction .
– Release the knob. The spring mechanism will remain in
the "ready" position ⇒.
– Pull the ball joint down out of the mounting fixture.
– Then swivel the socket up ⇒fig. 244 as far as it will go.
The mounting fixture will be closed automatically.
– Put away the ball joint attachment under the floor panel
in the luggage compartment.
WARNING
Make sure that the socket unit has closed off the mounting fixture
of the towing bracket properly. Otherwise the ball joint may fail to
engage securely if dirt accumulates in the mounting fixture.
Fig. 243 Removable
towing bracket:
Removing the ball joint
Fig. 244 Area below
rear bumper: Folding
up the socketA8
Aa
Ab
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Fuel and filling the tank 252Filling the tankFilling the tankThe flap that covers the tank cap is unlocked and locked
automatically by the central locking.
Unscrewing the tank cap
– Press the left side of the flap to open it ⇒fig. 247 -arrow-.
– Unscrew the tank cap anti-clockwise.
– Hook the cap onto the open flap ⇒fig. 248.Closing the tank cap
– Screw on the tank cap clockwise until it cannot be turned
further.
– Press the left side of the flap to close it (you should hear
it click into place).
When the automatic filler nozzle is operated correctly it will switch
itself off as soon as the tank is “full”. Do not try to put in more fuel
after the nozzle cuts out, as this will fill the expansion chamber in
the fuel tank.
The correct fuel grade for your vehicle is given on a sticker on the
inside of the tank flap. Further notes on fuel ⇒page 251.
The tank capacity of your vehicle is given in the Technical data
section ⇒page 321.
WARNING
Fuel is highly inflammable and can cause serious burns and other
injuries.•
For safety reasons always switch off the auxiliary heating*
before refuelling the vehicle.
•
For safety reasons we do not recommend carrying a spare fuel
canister in the vehicle. The canister could become damaged in an
accident and leak.
•
Observe all relevant statutory regulations on using, storing and
transporting spare fuel canisters.
•
When filling your tank or a spare fuel canister with fuel, do not
smoke and keep away from naked flames. Risk of explosion!
•
If, in exceptional circumstances, you have to carry a spare fuel
canister, please observe the following warnings:
−Never fill fuel into the spare fuel canister with the canister
placed in or on top of the vehicle. An electrostatic charge could
build up during filling, causing the fuel vapour to ignite. Danger
of explosion. Always place the canister on the ground to fill it.
Fig. 247 Vehicle as
seen from the rear
right: Opening fuel
tank flapFig. 248 Fuel tank flap
with tank cap attached
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Fuel and filling the tank253
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data −Insert the filler nozzle as far as possible into the spare fuel
canister.
−If the spare fuel canister is made of metal, the filler nozzle
must be in contact with the canister during filling. This helps
prevent an electrostatic charge building up.
−Make sure you never spill fuel in the vehicle or in the luggage
compartment. Fuel vapour is explosive. Risk of fatal accident!
Caution
•
If any fuel is spilt onto the vehicle, it should be removed immedi-
ately, as it could otherwise damage the paintwork.
•
Never run the tank completely dry. If there is an irregular fuel
supply, misfiring can occur. As a result unburnt fuel can enter the
exhaust system and cause damage to the catalytic converter(s).
•
When filling the fuel tank after having run it completely dry on a
vehicle with a diesel engine the ignition must be switched on for at
least 30 seconds without starting the engine. When you then start
the engine it may take longer than normal (up to one minute) for the
engine to start firing. This is because air needs to be bled from the
fuel system while starting.For the sake of the environment
Do not try to put in more fuel after the automatic filler nozzle has
switched off; this may cause the fuel to overflow if it becomes warm.
Note
The tank flap is not locked when you lock the vehicle from the
inside.
Releasing the tank flap manually
The tank flap can be released manually if the central
locking system should fail to operate.The manual release mechanism is located behind the side
trim on the right of the luggage compartment.
– Open the right-hand side trim.
– Release the ring from its holder and pull the ring
⇒fig. 249. You should now be able to open the tank flap
in the usual way ⇒page 252.
WARNING (continued)
Fig. 249 Luggage
compartment:
Releasing the fuel tank
flap manually
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Checking and topping up fluids 254Checking and topping up fluidsBonnetReleasing the bonnet
The bonnet is released from inside the vehicle.– Open the driver's door.
– Pull the lever under the dashboard in the direction indi-
cated (arrow) ⇒fig. 250.The bonnet springs out of its lock.
Opening the bonnetBefore opening the bonnet make sure that the windscreen
wiper arms are not lifted away from the glass. Otherwise the
paint may get damaged.
– Lift the bonnet slightly ⇒.
– Press the release catch under the bonnet upwards
⇒fig. 251. This will release the arrester hook.
– Open the bonnet.The bonnet is held open by two gas-filled struts.
WARNING
To avoid the risk of being scalded, never open the bonnet if you see
steam or coolant escaping from the engine compartment. Wait
until no steam or coolant can be seen before opening the bonnet.
Fig. 250 Detail of foot-
well on driver's side:
Release lever
Fig. 251 Release catch
under the bonnet
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Checking and topping up fluids261
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
The coolant additive G12++ can be mixed only with additives
G12+ 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. 257. 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 33. 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. 257 with a
cloth, and carefully unscrew the cap anti-clockwise
⇒.
– Add coolant.
– Screw the cap on again tightly.Make sure that the coolant meets the required specifications
⇒page 260, “Coolant”. Do not use a different type of additive if anti-
freeze additive G12++, G12+ or G12 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.
Fig. 257 Engine
compartment: Mark-
ings on radiator expan-
sion tank
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Checking and topping up fluids263
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
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.
For the sake of the environment
If the fluid has to be drained out of the brake system, use an appro-
priate container to catch the used brake fluid and dispose of it in the
proper manner.BatteryGeneral notes
All work on batteries requires specialist knowledge.The battery is virtually maintenance-free. It is checked as part of the
Inspection Service.
We recommend that you replace a battery once it is older than 5
years.
When an airbag is triggered, the battery will, under certain circum-
stances, be disconnected from the on-board power supply for
safety reasons ⇒ in “General notes on airbag system” on
page 201.
Disconnecting the battery
If the battery is disconnected, some of the vehicle's functions will
become inoperative (e.g. electric windows). These functions will
require resetting after the battery is reconnected. For this reason,
the battery should only be disconnected from the vehicle's electrical
system when absolutely necessary.
If the vehicle is not used for long periods
If you do not drive your vehicle for a period of several days or weeks,
the power management will gradually shut off the on-board
systems one by one, or reduce the amount of current they are using.
This limits the amount of power consumed and helps to ensure reli-
able starting even after a long period ⇒page 226.
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