engine AUDI A4 2008 B8 / 4.G Repair Manual

Automatic gearbox167
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Shifting up a gear
– Briefly push the selector lever forwards (in the tiptronic
gate) ⇒page 166, fig. 180 .
Shifting down a gear
– Briefly pull the selector lever backwards (in the tiptronic
gate) .With the tiptronic system the driver can manually choose between
7 different pre-programmed gears. The manual programme can be
selected either with the vehicle stationary or on the move.
When accelerating, the gearbox automatically shifts up into the next
gear shortly before the maximum engine speed is reached.
If you select a gear which is lower than the gear shown in the instru-
ment display ⇒page 166, fig. 181, the gearbox will only shift down
when there is no longer a risk of overrevving the engine.
When the vehicle slows down (for instance when braking), the
gearbox automatically shifts down into the next gear when the
minimum engine speed is reached.
Changing down to a lower gear increases the engine braking effect
on downhill gradients.
When the accelerator pedal is pressed right down past the point of
resistance at full throttle, the gearbox will select a lower gear,
depending on road speed and engine speed.Applies to vehicles: with multitronic® or tiptronicBack-up programme
A back-up system is in place should a fault occur in the
control system.The automatic gearbox switches to the back-up programme if a fault
should occur in the control system. This is indicated by all segments of the display panel either lighting up together or going out
completely.
It is still possible to move the selector lever to all positions. The
manual shift programme (tiptronic) is not available when the back-
up programme is active.
Vehicles with tiptronic gearbox: When the selector lever is in posi-
tion D or S or in the manual shift programme, the gearbox will
remain in 3rd gear if 1st, 2nd or 3rd gears were engaged when the
fault occurred. The gearbox will remain in 5th gear if 4th, 5th or 6th
gears were engaged. The gearbox will then engage 3rd gear when
you drive away from a standstill or after the engine is restarted.
It will still be possible to use reverse gear in the normal way.
However, the electronic lock for reverse gear will be switched off.
Caution
Should the gearbox ever switch into the back-up programme, you
should take the vehicle to an Audi dealer or qualified workshop as
soon as possible.Applies to vehicles: Paddle leversSteering wheel with paddle levers
The paddle levers on the steering wheel enable the driver
to manually select pre-programmed ratios or gears.
A+
A…
Fig. 182 Steering
wheel: tiptronic
switches
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HomeLink 180
At the operating unit
1. Switch on the ignition (do not start the engine).
2. Press and hold down the two outer HomeLink buttons
⇒page 179, fig. 197 until the indicator diode
⇒page 179, fig. 197 begins to flash after about
20 seconds. This procedure will delete the standard
factory settings and does not need to be repeated when
programming the other buttons.
3. Press the particular HomeLink button which you would
like to program.
4. Wait until the diode begins to flash. The HomeLink
module now remains in training mode for 5 minutes.
5. Now step in front of your vehicle with the original hand-
held transmitter for the garage door opener or any other
device you wish to assign to the HomeLink control
button.
At the radiator grille
6. Hold the original hand-held transmitter at or near the
centre of your car's radiator grille ⇒page 179, fig. 198.
7. Press the activator button on the original hand-held
transmitter.
8. As you do so, watch the turn signals on your vehicle.
HomeLink confirms successful programming by flashing
all four turn signals three times.
9. If the turn signals fail to flash three times, repeat the
procedure with the transmitter held at a different
distance from the radiator grille.
The proper distance between the hand-held transmitter and the
HomeLink module at the radiator grille depends on the system you
want to train. It may require several attempts.
The turn signals will flash once if the time limit for the programming
mode has been exceeded. In this case the programming procedure
needs to be performed again. Repeat the sequence at the operating
unit starting with step 3.
The programming instructions above also apply to the other control
buttons. Start with step 3 if you wish to proceed and program the
other two buttons.
If the garage door or other devices still fail to be activated with the
HomeLink control buttons after programming is completed, it is
possible that these systems might be working with a rolling code
instead of the normal fixed security code. If this is the case, a rolling
code programming is required in addition to the steps described
above. ⇒page 180Applies to vehicles: with HomeLinkRolling code programming
Some devices require rolling code programming of the
HomeLink universal transmitter.Identifying a rolling code
– Press the already programmed HomeLink button again
and hold it down.
–Watch HomeLink diode ⇒page 179, fig. 197. If the
diode starts flashing rapidly and turns into a constant
light after about 2 seconds, this indicates that the device
you wish to operate (e.g. a garage door opener) is
equipped with a rolling code.
– Program the rolling code as follows:
AA
AA
AA
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HomeLink181
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Activating the garage door opener drive unit
– Locate the programming button on the garage door
drive. The exact location and colour of the button may
vary depending on the type of garage door opener.
– Press the programming button on the door drive unit
(this will normally cause a “programming mode indicator
lamp” on the unit to light up). You now have about 30
seconds to start and complete the programming of the
HomeLink control button on the operating unit.
Programming at the operating unit in the
headliner
– Press and release the already programmed HomeLink
button.
– Press the HomeLink button again to complete rolling
code programming.After programming at the operating unit in the headliner, the
garage door opener should recognize the HomeLink signal and
respond when the HomeLink button is pressed. Now the other
control buttons can be programmed as required.
Note
•
Having a second person assist you makes programming of the
rolling code easier and faster. For some makes of garage door
openers the HomeLink button may have to be pressed a third time
to complete the training sequence.
•
If you encounter problems programming the rolling code you
may find helpful information in the operating instructions of the
garage door opener or other device you wish to operate.
Applies to vehicles: with HomeLinkOperating HomeLink
The programmed devices are activated by means of the
HomeLink control buttons in the headliner.– Make sure that the ignition is on.
– Press the programmed HomeLink button ⇒page 179,
fig. 197. The device assigned to that button (e.g. garage
door) will be activated.The HomeLink indicator diode ⇒page 179, fig. 197 will light up
when you press the button.Applies to vehicles: with HomeLinkErasing the button programming
You can erase the complete HomeLink programming by
pressing the two outer buttons.– Switch on the ignition (do not start the engine).
– Press and hold down the two outer buttons until the indi-
cator diode starts to flash ⇒page 179, fig. 197.
– Then release the buttons.After the programming of the HomeLink buttons has been erased,
the system will return to the training mode and is ready to be re-
programmed at any time.
Note
•
Programmed buttons cannot be erased individually.
•
For security reasons it is advisable to erase the programming of
the HomeLink buttons prior to selling your vehicle.
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Intelligent technology 222Intelligent technologyElectronic stabilisation program (ESP)DescriptionESP increases the car's stability. It reduces the tendency to skid and
improves the stability and roadholding of the vehicle. ESP detects
critical handling situations, such as understeer, oversteer and
wheelspin on the driven wheels. It stabilises the vehicle by braking
individual wheels or by reducing the engine torque. The warning
lamp
 in the instrument cluster starts flashing as soon as the ESP
intervenes.
The ESP incorporates the functions of the anti-lock brake system
(ABS), the traction control system (ASR), the electronic differential
lock (EDL) and the dynamic steering*.
Anti-lock brake system (ABS)
ABS prevents the wheels from locking up under braking until the
vehicle has reached a virtual standstill. You can continue to steer the
vehicle even when the brakes are on full. Keep your foot on the brake
pedal and do not pump the brakes. You will feel the brake pedal
pulsate while the anti-lock brake system is working.
Brake assist system
The brake assist system can speed up the braking process and
shorten the braking distance. It automatically boosts the braking
force if you press the brake pedal quickly in an emergency. On vehi-
cles with adaptive cruise control*, the brake assist system will build
up a small amount of pressure in the hydraulic brake system if it
senses that you are too close to the vehicle in front.
Traction control system (ASR)
In the event of wheelspin, the traction control system reduces the
engine torque to match the amount of grip available. This helps the
car to start moving, accelerate or climb a gradient.Electronic differential lock (EDL)
When the EDL detects wheelspin, it brakes the spinning wheel and
directs the power to the other driven wheel (or wheels on quattro*
versions). This function is active up to about 100 km/h.
To prevent the disc brake of the braked wheel from overheating, the
EDL cuts out automatically if subjected to excessive loads. The
vehicle can still be driven. The EDL will switch on again automati-
cally when the brake has cooled down.
Dynamic steering*
On vehicles with dynamic steering*, the ESP can also intervene in
the steering to stabilise the vehicle in critical situations.
WARNING
•
The grip provided by the ESP, ABS, ASR, EDL and dynamic
steering* systems is still subject to the physical limits of adhesion.
Always bear this in mind, especially on wet or slippery roads. If
you notice the systems cutting in, you should reduce your speed
immediately to suit the road and traffic conditions. Do not let the
extra safety provided tempt you into taking any risks when driving
– this can cause accidents.
•
Please remember that the accident risk always increases if you
drive fast, especially in corners or on a slippery road, or if you
follow too close behind the vehicle in front of you. Please bear in
mind that even ESP, ABS, brake assist, EDL, ASR and dynamic
steering* cannot compensate for the increased accident risk.
•
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 integrated control systems), which would impair the car's
stability and could lead to an accident.
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Intelligent technology223
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.
•
Should a malfunction occur in the ABS or EDL, both the ABS
warning lamp
 and the ESP warning lamp
 ⇒page 19 will light
up.
•
In the event of a malfunction in the ESP system, the warning
lamp  ⇒page 17 will light up.
•
If a malfunction should occur in the ABS, the ESP, EDL and ASR
will also be out of action.
•
The systems can make noises when they intervene.
Switching on and off
The ESP is switched on automatically when the engine is
started.
Switching off the traction control system (ASR)
In particular circumstances, it may be advisable to switch off the
traction control system (ASR) to allow a certain amount of wheel
slip. For example:•
Rocking the car backwards and forwards to free it
•
Driving in deep snow or on loose surfaces
•
Driving with snow chains
Press the button briefly ⇒fig. 232 or ⇒fig. 233. The
warning lamp
 will light up and the message ASR off will appear
in the driver information system display.
The traction control system (ASR) can only be switched off at speeds
below 50 km/h on vehicles with front-wheel drive. At 70 km/h it will
switch on again automatically. The ASR can be deactivated at any
speed on vehicles with four-wheel drive.
Switching off the ESP
Press the button for longer than 3 seconds. The ESP
warning lamp  will light up and the message ESP switched off will
appear in the display. The ASR is also deactivated when the ESP is
switched off.
Switching on
Press the button again. The message ESP/ASR on will
appear briefly on the display.
Fig. 232 Version A:
Centre console
(bottom), ESP OFF
button
Fig. 233 Version B:
Centre console (top),
ESP OFF button
ESP OFFESP OFFESP OFF
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Intelligent technology 224
WARNING
You should switch off the ESP only if your driving ability and traffic
conditions allow you to do so safely. Please note that, when the
ASR and ESP are switched off, the driven wheels may start to spin,
causing the vehicle to lose grip, in particular on slippery or wet
roads - danger of skidding!
Note
The ASR and ESP cannot be switched off when the adaptive cruise
control (ACC)* is on.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
factors 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.
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Intelligent technology225
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
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.
Power steering (servotronic)The power steering assists the driver when turning the
steering wheel (with the engine running).The power steering assists the driver by reducing the force needed
to turn the steering wheel. The degree of power assistance is
adapted electronically, depending on the speed.If a fault should occur in the servotronic system the power steering
will still operate. The degree of power assistance will, however, no
longer adapt to different speeds. If the electronic regulating system
is not working properly, this is most noticeable when turning the
steering wheel at low speeds (for instance when parking) – more
effort will be required than usual. The fault should be corrected by
a qualified workshop as soon as possible.
The power steering does not function when the engine is switched
off. In this case the steering wheel is very hard to turn.
If the steering is held at its turning limit when the car is stationary,
this will place an excessive load on the power steering system. In
this case, the power steering system will make noises. It will also
reduce the idling speed of the engine.
Caution
Do not keep the steering in the full-lock position for longer than
15 seconds when the engine is running – this could cause damage
to the power steering system.
Note
•
If the power steering should fail at any time or the engine is
switched off (for instance when being towed), the car can still be
steered. However, more effort will be required to turn the steering
wheel.
•
If the system is leaking or malfunctioning, please take the car to
a qualified workshop as soon as possible.
•
The power steering requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the
left ⇒page 256. The correct fluid level in the reservoir is important
for the power steering to function properly. The hydraulic fluid level
is checked at the Inspection Service.
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Intelligent technology 226Applies to vehicles: with four-wheel driveFour-wheel drive (quattro
®)
On quattro models the engine power is distributed to all
four wheelsGeneral notes
On four-wheel drive vehicles, the engine power is distributed to all
four wheels. The distribution of power is controlled automatically
according to your driving style and the road conditions. Also refer
to ⇒page 222, “Description”.
The four-wheel drive is specially designed to complement the supe-
rior engine power of your Audi. This combination gives the car
exceptional handling and performance capabilities – both on
normal roads and in more difficult conditions, such as snow and ice.
Even so (or perhaps especially for this reason), it is important to
observe certain safety points ⇒.
Winter tyres
Thanks to its four-wheel drive, your car will have plenty of traction
in winter conditions, even with the standard tyres. Nevertheless, we
still recommend that winter tyres or all-season tyres should be fitted
on all four wheels when winter road conditions are expected, mainly
because this will give a better braking response.
Snow chains
On roads where snow chains are mandatory, this also applies to cars
with four-wheel drive ⇒page 273, “Snow chains”.
Replacing tyres
On vehicles with four-wheel drive, all four tyres must have the same
rolling circumference. Also avoid using tyres with varying tread
depths ⇒page 270, “Replacing wheels and tyres”.Off-roader?
Your Audi does not have enough ground clearance to be used as an
off-road vehicle. It is therefore best to avoid rough tracks and
uneven terrain as much as possible.
WARNING
•
Even with four-wheel drive, 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 acci-
dents.
•
The braking ability of your car is limited by the grip of the tyres.
In this respect, your car is no different from a car without four-
wheel drive. So do not be tempted to drive too fast on icy or slip-
pery roads just because the car still has good acceleration in these
conditions (accident risk).
•
On wet roads bear in mind that the front wheels may start to
“aquaplane” and lose contact with the road if the car is driven too
fast. If this should happen, there will be no sudden increase in
engine speed to warn the driver, as with a front-wheel drive car. So
do not drive too fast in the wet: adjust your speed to suit the
conditions (accident risk).
Power managementThis system helps to ensure reliable starting
The power management controls the distribution of elec-
trical energy and thus helps to ensure that there is always
enough power available to start the engine.If a vehicle with a conventional electrical system is left parked for a
long time, the battery will gradually lose its charge because certain
electrical equipment (such as the immobiliser) continues to draw
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Intelligent technology227
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data current even when the ignition is off. In some cases there may not
be enough power available to start the engine.
Your vehicle is equipped with an intelligent power management
system to control the distribution of electrical energy. This signifi-
cantly improves reliability when starting the engine, and also
prolongs the life of the battery.
The main functions incorporated in the power management system
are battery diagnosis, residual current management and dynamic
power management.
Battery diagnosis
The battery diagnosis function constantly registers the condition of
the battery. Sensors detect the battery voltage, battery current and
battery temperature. This enables the system to calculate the
current power level and charge condition of the battery.
Residual current management
The residual current management reduces power consumption
while the vehicle is parked. It controls the supply of power to the
various electrical components while the ignition is switched off. The
system takes the battery diagnosis data into consideration.
Depending on the power level of the battery, the individual electrical
components are switched off one after the other to prevent the
battery from losing too much charge and to ensure that the engine
can be started reliably.
Dynamic power management
While the vehicle is moving, this function distributes the available
power to the various electrical components and systems according
to their requirements. The power management ensures that on-
board systems do not consume more electrical power than the
alternator can supply, and thus maintains the maximum possible
battery power level.
Note
•
The power management system is not able to overcome the
given physical limits. Please remember that the power and life of
the battery are limited.
•
A warning message will appear ⇒page 228, “Driver message in
the instrument cluster display” if the battery power has dropped to
a level where reliable starting is impaired.
Points to remember
Starting ability has first priority.Short trips, city traffic and low temperatures all place a heavy load
on the battery. In these conditions a large amount of power is
consumed, but only a small amount is supplied. The situation is also
critical if electrical equipment is in use when the engine is not
running. In this case power is consumed when none is being gener-
ated.
In these situations you will be aware that the power management
system is intervening to control the distribution of electrical power.
When the vehicle is parked 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.
Please note that certain convenience features, such as the Audi
advanced key*, the remote control key or the electrical seat adjust-
ment may not be available when you unlock the vehicle. These func-
tions will be restored when you switch on the ignition and start the
engine.
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Intelligent technology 228With the engine switched off
If you listen to the radio or use the other MMI functions when the
engine is not running, this will discharge the battery.
The MMI display will show this warning message before the battery
power drops to a level where the starting ability is impaired.
Please start engine, otherwise system will switch off
in 3 minutes.
This message warns you that the system you are using will be
switched off automatically after 3 minutes. You should therefore
start the engine if you wish to continue using the system.
When the engine is running
Although the alternator generates electrical power, the battery can
still become discharged while the vehicle is being driven. This can
occur when a lot of power is being consumed but only a small
amount supplied, especially if the battery is not fully charged
initially.
To restore the necessary energy balance, the system will then
temporarily shut off the electrical components that are using a lot
of power, or reduce the current they are consuming. Heating
systems in particular use a large amount of electrical power. If you
notice, for instance, that the seat heating* or the rear window
heater is not working, they may have been temporarily switched off
or regulated to a lower heat output. These systems will be available
again as soon as sufficient electrical power is available.
You may also notice that the engine runs at a slightly faster idling
speed. This is quite normal, and no cause for concern. The increased
idling speed allows the alternator to meet the greater power
requirement and charge the battery at the same time.
Driver message in the instrument cluster displayIf battery power drops to a level at which you may encounter prob-
lems when starting the engine, the following message will appear
in the instrument cluster display:
 Low battery charge: Battery will be charged while driving
This message reminds you that the starting reliability may be
impaired. The message will disappear as soon as you set off and the
battery is charged.
Message comes on and goes out again
If the message appears in the display after the ignition is switched
on or while driving, and goes out again after a period of time, the
battery has been charged up again sufficiently while the vehicle was
being driven.
Message comes on and does not go out
If the message appears in the display after the ignition is switched
on or while driving, and does not go out again, the battery is not
being maintained at the proper power level. Starting reliability may
be impaired. You should have the battery checked by a qualified
workshop as soon as possible.
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