technical data AUDI A4 2008 B8 / 4.G Manual PDF

adaptive cruise control (ACC)141
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data Driving into a bend
When you are driving into a bend, the ACC system may react to a
vehicle travelling in the other lane and therefore brake the vehicle
⇒page 140, fig. 149. You can override the braking effect by pressing
the accelerator.
Driving out of a bend
When you are driving out of a long bend, the ACC system may - in
the course of its calculation of the lane ahead - react to a vehicle
travelling in the other lane and therefore brake the vehicle
⇒page 140, fig. 150. You can override the braking effect by pressing
the accelerator.
Applies to vehicles: with adaptive cruise controlVehicles in front travelling out of lineVehicles in front which are not in line with your vehicle cannot be
detected by the ACC system until they are within the range of the
sensor.
Applies to vehicles: with adaptive cruise controlOther vehicles changing lanesVehicles which are very close to you when they move onto your lane
cannot be detected by the radar sensor until they move into its
range.Applies to vehicles: with adaptive cruise controlNot clearly discernible vehiclesVehicles that are not clearly discernible, e.g. a motorcycle travelling
in front of you and vehicles with a large amount of ground clearance
or protruding freight, are often identified late or may not be
detected at all.
Fig. 151 The vehicle in
front is outside the
range of the radar
sensor
Fig. 152 A vehicle is
changing lanesFig. 153 Motorcycle in
front
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adaptive cruise control (ACC)143
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Safety
Driving tips
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Technical data which can shorten the system response time. The warning will be
deactivated if you press the accelerator pedal right down in order to
overtake.
The system draws the driver's attention to two different hazardous
situations:
Distance !
A distance warning will be given if you travel too close to the vehicle
in front for longer than 5 seconds. For example, if the distance is
less than 9 m at 80 km/h, a message will appear in the instrument
cluster display ⇒page 142, fig. 156.
If the vehicle in front were to brake hard, a collision would no longer
be avoidable, even if you reacted immediately. In this case, you
should leave more room between your car and the vehicle in front.
Speed
If the vehicle in front of you is travelling in the same lane at a much
slower speed or if it brakes hard, the Audi braking guard will calcu-
late the time at which a collision can be avoided only by emergency
braking or evasive action. When the system warns you, it is possible
to avoid a potential collision with the vehicle in front by braking or
changing lane. There are two warning levels:
•
Early warning: A message will appear in the instrument cluster
display and you will also hear a warning tone.
•
Acute warning: The second (acute) warning will be triggered if
you do not react to the advance warning. There will automatically be
a short dab of the brakes to remind you to concentrate on the traffic.
If you brake hard, the brake assist system ⇒page 222 helps you to
achieve the optimum braking effect.
WARNING
Please always direct your full attention to the road, even when the
Audi braking guard is activated. It is always you who is responsible for determining your speed and for keeping a safe distance to the
other vehicles on the road.
•
Always maintain the statutory minimum safety distance to the
vehicle in front (risk of accident).
•
Due to the system limitations, the Audi braking guard will not
react in certain situations, for example when approaching a
stationary obstacle (such as the end of a traffic jam or a broken-
down vehicle).
•
Please note that the Audi braking guard is subject to limita-
tions in tight bends on account of the radar sensor's field of vision.
This means that obstacles may not be detected in certain situa-
tions.
•
The radar sensor's "field of vision" can be impaired by rain,
snow or a lot of water on the road. This results in vehicles not
being reliably recognised or, in some circumstances, not being
detected at all. Always keep the road ahead within your field of
vision.
•
Reflecting objects, such as crash barriers or the entrance to a
tunnel, could impair the function of the radar sensor.
Applies to vehicles: with adaptive cruise controlStatus messages in the instrument cluster displaybraking guard brake jolt
This driver message appears when the brakes are dabbed due to an
acute warning.
braking guard off
This driver message appears when the system is switched off in the
MMI. The message also appears briefly after you begin driving if the
system is switched off.
WARNING (continued)
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Audi lane assist145
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Audi lane assistAudi lane assistApplies to vehicles: with lane assistDescription
The lane assist system assists the driver in keeping the
vehicle in the right lane.The system uses a camera to detect the markings of the lane you are
driving in. If the vehicle approaches one of the detected lane mark-
ings, the steering wheel vibrates to warn the driver that the vehicle
might be about to cross one of the markings. The lane assist system
is functional when it has detected lane markings on both sides of
the lane you are driving in. The green lamp
 in the instrument
cluster indicates that the function is activated and fully functional.
If you operate the turn signal before crossing one of the lane mark-
ings (while the lane assist system is functional), the system will
detect that the lane change is intended and will not warn the driver.
As the system is designed for driving on motorways and other major
roads, it is only active above a speed of about 65 km/h.
WARNING
•
The lane assist system does not keep the vehicle in its lane. It
merely warns the driver when the vehicle is in danger of crossing
the markings of the lane. As the driver you are always responsible
for staying in your own lane.
•
The camera cannot detect all lane markings. Therefore it is
possible that variations in the road surface or objects might be
detected as lane markings, which can lead to false warnings, or
warnings not being given.
•
The camera's view might be obstructed, for example by vehi-
cles travelling in front, rain, snow, a lot of water on the road or adverse light. This can result in the system not detecting the lane
markings correctly.
Applies to vehicles: with lane assistSwitching on and off– Press the button ⇒fig. 158 -arrow- to switch the system
on and off. The indicator lamp

in the instrument
cluster will light up or go out.
WARNING (continued)
Fig. 158 Turn signal
lever: Pushbutton for
Audi lane assistFig. 159 Windscreen:
Camera window for
Audi lane assist
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Audi lane assist147
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Technical data
•
Unfilled lines: The lane assist is switched on but not ready for
warning ⇒page 146, fig. 161,
Version : High-resolution display
•
Solid white lines: The lane assist is switched on and ready to
warn.
•
Solid red line (left or right): The lane assist warns you before you
cross the lane demarcation ⇒page 146, fig. 160.
•
Unfilled lines: The lane assist is switched on but not ready for
warning ⇒page 146, fig. 161.
Messages in the instrument cluster display
Should the lane assist be deactivated automatically, the indicator
lamp in the instrument cluster will go out and one of the following
messages will appear in the instrument cluster display:
Audi lane assist not available: currently no sensor vision
This message is displayed when the camera is no longer functional
after the system has continuously failed to detect the lane mark-
ings. This can have the following causes:
•
The outside of the camera window ⇒page 145, fig. 159 is dirty
or frosted. Please remove dirt or ice from this area of the wind-
screen.
•
The inside of the camera window is misted up. In this case,
please wait for the camera window to demist before switching on
the lane assist system again.
•
Due to the conditions (e.g. snow-covered road) the system has
not been able to detect the lane markings for a long period. Do not
switch the lane assist system on again before the lane markings are
discernible.
Audi lane assist currently not available
A temporary error is preventing the lane assist system from fully
functioning. Try switching on the lane assist system again later.
Audi lane assist: system faultThe system should be checked by an Audi dealership or other qual-
ified workshop.
Applies to vehicles: with lane assistSetting the warning time and steering vibration
You can change the lane assist settings on the sound
system or MMI* to suit your individual preferences.– Select: Function selector button > Audi lane assist.Setting time of warning
early: In this setting, the driver will be warned before a wheel
crosses a lane marking. The warning depends on the angle with
which the vehicle is approaching the lane marking. The larger the
angle with which you are driving towards the marking, the earlier
you will receive the warning, i.e. the distance between the vehicle
and the marking might still be still relatively long. If you are driving
toward the marking at a very narrow angle, you will receive the
warning later, i.e. shortly before one of the wheels touches the
marking.
adaptive: In this setting, the time of warning is adapted to the road
layout and the vehicle's speed. The warning will be received later
when you are driving through a bend, and earlier when you are
AA
AB
Fig. 162 Display:
Setting time of
warning and steering
vibration
CAR
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Audi side assist149
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Audi side assistLane change assist featureApplies to vehicles: with side assistDescription
The side assist function assists the driver when changing
lanes.The side assist function employs radar sensors ⇒fig. 163 to assist
the driver in monitoring following traffic and the blind spots on both
sides of the car ⇒page 151, fig. 166.Warning lamps are incorporated in the two exterior mirrors
⇒fig. 164. The warning lamp on the left-hand mirror assists the
driver when changing lane towards the left and the warning lamp
on the right-hand mirror assists the driver when changing lane
towards the right.
When one of these lamps lights up, this is to inform you that the
side assist has detected a vehicle on that side and calculates that a
lane change would be critical. This is the first stage of the warning,
referred to as the information mode ⇒page 151. This stage of the
warning is designed to be visible only when you look in the exterior
mirror.
If you operate the turn signal when the side assist has registered
what it judges to be a critical vehicle, the lamp on the exterior mirror
will then flash several times with greater intensity. This is the
warning mode ⇒page 151.
Applies to vehicles: with side assistSwitching on and off
Fig. 163 Rear bumper:
Position of radar
sensors (not externally
visible)Fig. 164 Warning lamp
on exterior mirror
(driver's side)
Fig. 165 Driver's door:
Button for side assist
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Audi side assist151
Controls
Safety
Driving tips
General maintenance
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Technical data
Applies to vehicles: with side assistArea covered by the radar sensorsThe area covered by the radar sensors ⇒fig. 166 consists of:•
The rearward approach zone (light green area: up to about 50
metres) and
•
Blind spots (dark green area) .
The radar sensors monitor the lanes immediately to the left and
right of your vehicle. Other lanes are not covered by the sensors.Note
The side assist system is programmed for lanes of a fixed width, and
is not able to measure differing lane widths. It monitors a zone
equivalent to one normal lane width on either side. If the lanes are
narrower than this, or if vehicles are not travelling in the centre of
the lanes, the system may register vehicles that are not in fact trav-
elling in an adjacent lane ⇒page 156.Applies to vehicles: with side assistHow the system worksWhen other vehicles are detected, the side assist system registers
their distance and how fast they are approaching. The warning lamp on the relevant exterior mirror will light up whenever the side assist
calculates that the distance and the speed differential of
approaching vehicles would be critical in the event of a lane change.
The warning lamp may light up when you are being overtaken and
when you are overtaking another vehicle.
If you are overtaking slowly, with a speed differential of less than
15 km/h, the warning lamp will light up as soon as the other vehicle
enters your blind spot and is detected by the sensors. If you are
overtaking with a speed differential which is greater than this the
lamp will not give a warning.
Applies to vehicles: with side assistInformation mode and warning modeThe side assist has two modes of operation•
The information mode and
•
The warning mode
The side assist will respond in the appropriate mode, depending on
whether or not you operate the turn signal to indicate an intended
lane change.
Information mode
As long as you do not operate the turn signal, the side assist will
merely inform you of the presence of vehicles that it has detected
and judges to be critical in the event of a lane change. The warning
lamp on the relevant exterior mirror will light up with low intensity
whenever the side assist calculates that the distance and the speed
differential of an approaching vehicle are critical.
The intensity of the warning lamp in this information mode is delib-
erately kept relatively low, so that it does not distract you while you
are looking at the road in front and do not intend to change to a
different lane. The information mode is clearly visible when you look
in the exterior mirror.
Fig. 166 Schematic
diagram: Area covered
by the radar sensors
A1
A2
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Audi side assist153
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Technical data
Applies to vehicles: with side assistSituation with vehicle approaching slowly from behindFig. 168 side assist: Vehicles approaching slowly from behind and vehicles in
the blind spot Warning lamp on exterior mirror does not light up
The sensors have detected a slowly approaching vehicle - in this
example in the left-hand lane. Because it is relatively far away and
only approaching slowly, no warning will appear on the exterior
mirror ⇒ in “Safety notes” on page 157.
Warning lamp lights up in information mode
The slowly approaching vehicle is now closer. The warning lamp on
the exterior mirror lights up in the information mode.
The warning lamp on the exterior mirror will only light up if the side
assist calculates that the distance and the speed differential of
approaching vehicles would be critical in the event of a lane change. In all cases, the side assist will light up to indicate the vehicles it has
detected at the latest when they enter the “blind spot”.
Warning lamp flashes in warning mode
If you operate the turn signal in situation , the warning lamp on
the exterior mirror will flash briefly several times. This calls your
attention to the presence of a vehicle which you may have over-
looked.
Note
•
The faster a vehicle approaches, the earlier the warning will
appear on the exterior mirror. The side assist will give a warning for
the approaching vehicles it has detected at the latest when they
enter the “blind spot”.
•
If a vehicle is approaching at high speed it is possible that a lane
change may be critical, even though no warning is given.
A1A2
A3
A2
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Audi side assist155
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Technical data quickly. The warning lamp on the exterior mirror does not light up
⇒ in “Safety notes” on page 157.
Warning lamp on exterior mirror does not light up
If you operate the turn signal in situation , the warning lamp on
the exterior mirror will still not give any warning ⇒ in “Safety
notes” on page 157.
Applies to vehicles: with side assistAdjusting brightness of warning lamp on exterior mirror
You can adjust the brightness of the warning lamp on the
sound system or MMI*.– Select: Function selector button > Audi side assist
> Warning lamp: brightness.The brightness of the warning lamp in both the information and
warning modes is regulated automatically according to the ambient
light level. You can also adjust the basic brightness level of the
warning lamp yourself via the function Warning lamp: brightness.
The new brightness level will be displayed briefly while you are
making the adjustment. The brightness level that is shown at this
point is the intensity of the lamp when it comes on in the informa-tion mode. The intensity of the lamp in the warning mode is linked
to the intensity in the information mode.
The brightness of the lamp in the information mode should be set
so that you can see the lamp when you glance at the exterior mirror,
but are not aware of it when looking forwards through the wind-
screen.
If you are in very dark or very light surroundings when you adjust the
brightness of the warning lamp, the automatic brightness control
may already have reached the lowest or the brightest setting. Under
these circumstances the brightness of the warning lamp on the
exterior mirror may not change visibly when you alter the basic
brightness level.
If you adjust the basic brightness level while the vehicle is in in very
dark or very light surroundings, the change in the setting may only
become visible in surroundings of more moderate brightness.
Note
•
The side assist is not active while you are changing the bright-
ness setting; the brief flash of the warning lamp is only intended to
help you make the desired setting.
•
Your personal settings are stored automatically and assigned to
the remote control key which is being used.
Applies to vehicles: with side assistGeneral notesThe side assist system has inherent limitations in some situations.
For this reason, please take particular care:•
When driving through bends ⇒page 156
•
On roads with varying lane widths ⇒page 156.
A3
A2
Fig. 171 Display:
Adjusting brightness
of warning lamp
CAR
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Audi side assist157
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Technical data Audi side assist: system fault
The system should be checked by an Audi dealership or other qual-
ified workshop.
Audi side assist not available when towing
On vehicles with a factory-fitted towing bracket the side assist func-
tion will be switched off automatically when the electrical connector
for the trailer is plugged in, and this message will appear in the
instrument cluster display. The side assist function may not be
switched off automatically if the towing bracket is not of the factory-
fitted type.
Applies to vehicles: with side assistSafety notesThe function of the side assist can be restricted when driving in
tight bends or over crests and in bad weather conditions.
It is possible that the radar sensors may register objects such as
high or offset roadside barriers as well as other vehicles.
The side assist system is programmed for lanes of a fixed width, and
is not able to measure differing lane widths. It monitors a zone
equivalent to one normal lane width on either side. If the lanes are
narrower than this, or if vehicles are not travelling in the centre of
the lanes, the system may give a warning for vehicles which it
judges to be critical, even though they are not in fact travelling in an
adjacent lane.
WARNING
•
Please note that the sensors are not always able to detect all
vehicles which may represent a potential hazard (accident risk).
•
Please note that the side assist is not able to give adequate
warning of vehicles approaching very fast from behind, or vehicles
that you are overtaking rapidly.
•
The radar sensor's "field of vision" can be impaired by rain,
snow or a lot of water on the road. This results in vehicles not
being reliably recognised or, in some circumstances, not being
detected at all by the side assist. Always give your full attention to
the position of your vehicle on the road and other nearby traffic.
•
The side assist only gives a warning of approaching vehicles
and vehicles in the blind spots when road speed is above 60 km/h.
•
Please note that the side assist does not operate in tight bends
(with a radius of less than 200 metres).
•
The side assist feature is not a substitute for the full concentra-
tion of the driver. The driver is always responsible for the safety of
lane changes and other manoeuvres. Always give your full atten-
tion to the position of your vehicle on the road and other nearby
traffic.Caution
To avoid impairing the function of the side assist, do not attach any
objects (e.g. stickers or bicycle carriers) in such a way that they
might interfere with the radar sensors in the rear bumper.
Note
For reasons of safety, the side assist system must be checked by a
qualified workshop if the positions of the radar sensors have been
affected by a rear-end collision, etc.Applies to vehicles: with side assistConformity certificationThe side assist employs radar sensors operating in one of two
frequency bands at 24 GHz. Please note that in some countries only
one of these two frequency bands is permitted. Accordingly, the
frequency band permitted in the country where the vehicle is being
WARNING (continued)
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Audi drive select159
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Audi drive selectAdjusting the vehicle set-upApplies to vehicles: with Audi drive selectIntroductionAudi drive select allows you to use different set-ups on your vehicle.
Using the three modes COMFORT, AUTO and DYNAMIC, you can
change the set-up at the press of a button for a more comfort-
oriented or dynamic drive.
On vehicles with MMI*, you also have the INDIVIDUAL* mode, which
allows you to adapt the vehicle set-up individually to your personal
driving style. For example, you might choose to combine a more
dynamic engine set-up with a lighter steering response.Applies to vehicles: with Audi drive selectDescriptionThe possible vehicle set-up in each mode depends on which equip-
ment is installed on your vehicle. The engine and the servotronic
power steering are basic parts of your vehicle which are always
included in the set-up. In addition, you can change the characteris-
tics of the automatic gearbox*, dynamic steering* and suspension
control*.
The response of the engine and automatic gearbox* to accelerator
pedal movements will be more spontaneous or balanced,
depending on which mode you select.
The servotronic power steering ⇒page 225 will also respond to
different drive set-ups.
The dynamic steering* alters the steering ratio depending on the
road speed to optimise the amount of steering effort required by the
driver at any given time. This enables the sensitivity of the steering to be reduced at higher speeds in order to improve the handling of
the vehicle. The steering is more direct at lower speeds to minimise
the amount of steering effort required by the driver, e.g. when
manoevring in tight spaces. The dynamic steering* also provides a
more agile steering response at low and medium speeds. You can
adjust the basic characteristics of the steering in the Audi drive
select menu.
The suspension control* uses sensors to collect information on
steering movements, braking and acceleration input by the driver,
road surface quality, road speed and vehicle loading. Using this
information, the suspension can be adapted almost instantane-
ously to changing driving conditions. With Audi drive select, the
driver can choose between dynamic and comfort-oriented suspen-
sion set-ups (DYNAMIC and COMFORT modes), or opt for a more
balanced set-up (AUTO mode).
The following table provides an overview of the characteristics in
each driving mode.
If your vehicle is equipped with dynamic steering*, the servotronic
power steering settings are adjusted in the Dynamic steering*
menu.
Systems
COMFORT
AUTO
DYNAMIC
Engine or
engine/gearbox*
Balanced
Balanced
Dynamic
Steering
Comfortable
Balanced
Dynamic
Dynamic steering*
Comfortable
(indirect)
Balanced
(direct)
Dynamic
(direct)
Suspension control*
Comfortable
Balanced
Dynamic
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