2008 AUDI A4 main

adaptive cruise control (ACC) 130Applies to vehicles: with adaptive cruise controlHow does the distance control work?
Vehicles in front are detected by a radar sensor.The adaptive cruise control uses a radar sensor ⇒fig. 137 which is
integrated in the front of the vehicle and is subject to certain system
limitations ⇒page 140. Stationary objects are disregarded. The
system requires reflecting surfaces in order to be able to measure
the distance. If the ACC is unable to measure the distance it will not
respond.
No vehicle in front
When there is no vehicle in front, the adaptive cruise control works
like a speed control system. It maintains a constant target speed
specified by the driver.
Vehicle in front
If you catch up with a vehicle driving in front, the adaptive cruise
control will reduce the speed accordingly (within the limits set by
the system ⇒page 138, “Driver intervention prompt” and
⇒page 140, “System limitations”) and adapt it to the speed of the
vehicle in front. Then the system will try to adjust the distance to the
car in front according to the settings selected. During the adjust-
ment process the system may temporarily not be able to adhere to
the distance you had specified ⇒ in “Description” on page 128.If the vehicle in front accelerates, the adaptive cruise control will
also accelerate, up to the target speed you have specified.
Driver intervention prompt
In some situations, it is necessary for the driver to brake the vehicle
with the foot brake in order to keep a safe distance to the vehicle in
front or to avoid a collision. In this case, a warning message will
appear in the display and you will also hear a warning tone
⇒page 138.
When overtaking
When you move into the overtaking lane and no vehicle is detected
in front, the adaptive cruise control will accelerate up to the target
speed and then maintain it.
Overriding
You can still use the accelerator pedal at any time to increase speed
in the normal way. The previously programmed speed will be
resumed when the accelerator pedal is released.
Note
•
Please note that acceleration will vary depending on the preset
programme. If you have, for example, selected “Distance 1” and the
driving programme “dynamic”, acceleration will be more "sporty".
However, if you have set the system to “Distance 4” and driving
programme “comfort”, acceleration will be more gradual. For a
detailed description please refer to ⇒page 133, “Setting the
distance”.
•
No vehicle in front, Vehicle in front and a Driver intervention
prompt will be indicated by an indicator lamp ⇒page 134, “Indi-
cator lamp and display in the speedometer”.
Fig. 137 Area covered
by radar sensor
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adaptive cruise control (ACC)131
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Applies to vehicles: with adaptive cruise controlSwitching the system on and off– Pull the control lever to position ⇒fig. 138 to switch
on the system.
– Press the control lever to position (click stop engaged)
to switch the system off.Applies to vehicles: with adaptive cruise controlSetting the speedImportant: The system must be switched on.– Drive at the desired speed. The speed must be in the
range between 30 and 200 km/h.
– Press the button -arrow- ⇒fig. 139 to confirm the
target speed you wish to store.
When the button is released, the current speed is stored in the
memory and the vehicle will then maintain this speed.
One or two red diodes will light up in the speedometer dial
⇒page 134 to mark the speed which is currently stored in the
system. At the same time, the speed will briefly be displayed in the
system status indicator ⇒page 136.
Note
For safety reasons, the speed setting will be deleted when the igni-
tion is switched off.Applies to vehicles: with adaptive cruise controlSetting a new speed
The speed can be altered without touching the acceler-
ator or the brake.
Fig. 138 Control lever
for: Switching the
system on and off
A1A2
Fig. 139 Control lever
for: Setting speed
SET
SET
Fig. 140 Control lever
for: Setting a new
speed
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adaptive cruise control (ACC) 132
Setting a higher speed
–Briefly move the control lever up towards ⇒fig. 140.
The speed will be incremented by one graduation on the
scale in the speedometer.
– Press the control lever up towards and hold it in this
position. The speed setting is indicated by the diodes in
the speedometer; the speed will be increased accord-
ingly.
Setting a lower speed
–Briefly move the control lever down towards . The
speed will be reduced by one graduation on the scale in
the speedometer.
– Press the control lever down towards and hold it in
this position. The speed setting is indicated by the
diodes in the speedometer; the speed will be reduced
accordingly.After releasing the control lever, the system will adapt your speed to
the setting you have selected.
Following any changes, the new stored speed will be displayed
briefly in the system status indicator ⇒page 136.
Note
You can still use the accelerator pedal at any time to increase speed
in the normal way. The previously programmed speed will be
resumed when the accelerator pedal is released. You can set a new
speed at any time by pressing the button ⇒page 131,
fig. 139.
Applies to vehicles: with adaptive cruise controlSwitching off the system (with speed memory function) and reactivating it
In some situations it makes sense to switch off the
system.Switching off the system (with speed memory
function)
– Press the brake pedal, or
– Press the control lever in direction ⇒fig. 141.
Reactivating the system
– Release the brake pedal and pull the lever in direction .
WARNING
It is dangerous to resume a set speed which is too high for the
current road, traffic or weather conditions - risk of accident.
Note
When switching off the system (with speed memory function) the
speed stored at this point remains in the memory.
A+
A+
A-
A-
SET
Fig. 141 Control lever
for: Switching off the
system (with speed
memory function) and
reactivating it
A2
A1
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adaptive cruise control (ACC)133
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Applies to vehicles: with adaptive cruise controlSetting the distance
The distance can be set in 4 different stages.– Briefly press the sliding switch ⇒fig. 142 once towards
or . The display in the instrument cluster will briefly
show the current distance setting.
– Press the sliding switch again towards or to
increase or reduce the distance by one level at a time.Choosing the distance
The adaptive cruise control system determines the distance to the
vehicle in front by time intervals. It defines a time-based distance to
the vehicle in front which is kept at a constant level. This converts
to a distance which depends on the speed - the higher the speed,
the higher the safety distance in metres ⇒.
The actual distance maintained by the adaptive cruise control can
be longer or shorter, depending on the traffic situation and the
driving style of the driver in front.
Distance 1

This setting is suitable for brisk driving in a line of traffic. The time
interval is 1 second. This is equivalent to (for instance):•
A distance of 14 metres at a speed of 50 km/h
•
A distance of 36 metres at a speed of 130 km/h
Distance 2

This setting is suitable for relaxed “moving with the flow” in a line
of traffic. The time interval is 1.3 seconds. This is equivalent to (for
instance):•
A distance of 18 metres at a speed of 50 km/h
•
A distance of 47 metres at a speed of 130 km/h
Distance 3

This (recommended) setting is suitable for relaxed “moving with the
flow” in a line of traffic. The time interval is 1.8 seconds. This is
equivalent to (for instance):•
A distance of 25 metres at a speed of 50 km/h
•
A distance of 65 metres at a speed of 130 km/h
Distance 4

This setting is suitable for single-carriageway roads. The time
interval is 2.3 seconds. This is equivalent to (for instance):•
A distance of 32 metres at a speed of 50 km/h
•
A distance of 83 metres at a speed of 130 km/h
You can control the acceleration and braking response of your
vehicle in adaptive cruise control mode by adjusting the settings on
the sound system or MMI* ⇒page 139. Depending on the driving
program and distance selected, acceleration and braking response
will range from dynamic (1) to relaxed (5).
Fig. 142 Control lever
for: Setting the
distance
A+
A-
A+
A-
Driving pro-
gram
dynamic
standard
comfort
Distance 1
1
2
3
Distance 2
2
3
4
Distance 3
2
3
4
Distance 4
3
4
5
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adaptive cruise control (ACC)135
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data Target speed
The target speed set by the driver is indicated by a red diode in the
speedometer.
If the speed setting is between two graduations on the speedom-
eter dial, the two closest diodes will both light up ⇒fig. 143.
It is only possible to set target speeds ranging from 30 to 200 km/h.
This speed range is illuminated slightly by the diodes on the speed-
ometer dial.
Indicator lamp (symbol)
•
No vehicle in front: The green indicator lamp ⇒page 134,
fig. 144 shows that the adaptive cruise control system is in cruise
mode and that there is no vehicle in front. It maintains the stored
target speed.
•
Vehicle in front: The green indicator lamp shows that the
system has detected a vehicle in front. The speed is adapted to the
vehicle in front. The adaptive cruise control system accelerates and
brakes the vehicle automatically.
•
Driver intervention prompt: When the red indicator lamp
flashes , this is a warning for the driver to intervene. The driver
has to brake the vehicle with the foot brake. This warning lamp will
always appear when the adaptive cruise control system alone is not
able to brake the vehicle sufficiently to maintain a safe distance to
a vehicle in front. An audible alarm (warning tone) will also sound
when the lamp starts to flash. For further information on the driver
intervention prompt ⇒page 138.Note
•
If you exceed the target speed by using the accelerator, the
driver intervention prompt will not be accompanied by a warning
tone. The indicator lamp shown in the speedometer will also switch
off if the target speed is exceeded.
•
You can change the volume of the warning tone on the sound
system or MMI* ⇒page 139, “Setting the warning tone volume and
driving program”.
Applies to vehicles: with adaptive cruise controlInstrument cluster displayRepeatedly press the button on the windscreen wiper lever
to select whether you wish to display information regarding the on-
board computer, the navigation system* or the adaptive cruise
control in this section of the display screen.
Vehicle image
Distance
System status
Vehicle image
The vehicle image will show you whether the system has detected a
vehicle in front.•
Vehicle outlined: No vehicle in front
•
Vehicle in white: A vehicle in front has been detected
•
Vehicle in red: Driver intervention prompt
Distance
The arrows and scale indicate the distance to the vehicle in front.
•
No vehicle in front: If there is no vehicle in front, no arrows will
be shown.
AA
AA
AB
AB
AC
AC
Fig. 145 Instrument
cluster: Display
RESET
AAABACAAAB
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adaptive cruise control (ACC)137
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
The control lever has been pushed up / down to increase / reduce
the speed, but the resulting speed would be outside the range of 30
to 200 km/h.
ACC deactivation
The message ACC deactivation sometimes appears on vehicles with
a manual gearbox. If you press the clutch pedal for longer than
about 20 seconds, the adaptive cruise control will be automatically
deactivated and a warning tone will sound.
ACC not available
The text message ACC not available will appear if, for example, the
brakes are overheated. The adaptive cruise control will then tempo-
rarily not be available. This is indicated by a warning tone.
ACC not available!
The text message ACC not available! appears if a malfunction
should occur. The adaptive cruise control will then be switched off.
This is indicated by a warning tone. Have the system checked by a
qualified workshop.
ACC sensor blocked!
The text message ACC sensor blocked! appears if the ACC system
can no longer detect objects reliably. The adaptive cruise control
will then be switched off. This is indicated by a warning tone.
The ACC sensor is obstructed by dirt or foreign objects (e.g. leaves
or snow). Clean the sensor to restore the function ⇒page 128,
fig. 136.
Engine speed !
On vehicles with manual gearbox, the text message Engine speed !
will appear if the driver does not change gear in time when the
adaptive cruise control accelerates or brakes the vehicle. The adap-
tive cruise control will automatically be deactivated if the engine
speed is not maintained within the permissible range. This is indi-
cated by a warning tone.ESP activation
The text message ESP activation appears if the Electronic Stabilisa-
tion Programme (ESP) has intervened. In this case, the adaptive
cruise control will automatically be switched off. This is indicated by
a warning tone.
Speed (in km/h)
The target speed (in km/h) will appear in the display whenever it is
stored or changed ⇒page 131, “Setting the speed” and
⇒page 131, “Setting a new speed”.
Speed range
The text message speed range appears if the current speed is too
low to set or to maintain the target speed.
To set a target speed, the speed of the vehicle must be at least
30 km/h. The cruise control system switches off if the speed falls
below 20 km/h.
If the speed exceeds 200 km/h (OVERRIDE), the system will remain
active and will reduce the speed to 200 km/h once the driver stops
accelerating.
ACC functionality limited
The text message ACC functionality limited appears if the ACC
system does not detect any objects for an extended period. The
distance to vehicles in front is not being controlled while the
message is displayed. The ACC system is not deactivated, and so
extra care should be taken! The text message ACC functionality
limited can appear for the following reasons:
•
The ACC sensor is dirty. The ACC system is not responding or is
not responding correctly to the vehicles in front!
•
You may be driving on a country road with no traffic and no clear
roadside demarcation (e.g. safety barriers, traffic signs, trees). As
soon as the system detects a vehicle, distance control is resumed
and the text message disappears.
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adaptive cruise control (ACC) 138The ACC sensor is located inside the trim grille (front right)
⇒page 128, fig. 136. If the sensor is no longer functioning due to
dirt or obstruction in this area, it should be cleaned.
Parking brake !
The text message Parking brake ! appears if the parking brake is
operated. The adaptive cruise control will then be switched off. This
is indicated by a warning tone.
Gear lever position !
On vehicles with manual gearbox the text message Gear lever
position ! appears when no valid forward gear is selected, i.e.
reverse gear or 1st gear is engaged or the gear lever is in the neutral
position. Adaptive cruise control is not available when the lever is in
these positions.
Shift lever position!
On vehicles with automatic gearbox the text message Shift lever
position ! appears if the shift lever is moved to position N. Adaptive
cruise control is not available when the lever is in this position.
Applies to vehicles: with adaptive cruise controlDriver intervention prompt
The driver intervention prompt is a warning for the driver
to reduce speed manually.Fig. 147 Instrument cluster: Driver intervention promptIn some situations the adaptive cruise control system alone is not
able to brake the vehicle sufficiently to maintain a safe distance to
the vehicle in front. The adaptive cruise control system will then call
on you as the driver to take control of the situation yourself.
The Driver intervention prompt provides both a visual and an
acoustic warning.•
A red vehicle symbol will appear in the instrument cluster
display ⇒fig. 147.
•
The system status indicator will show DISTANCE!.
•
The red warning lamp will start to flash.
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adaptive cruise control (ACC)139
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
An acoustic warning will also sound (unless it has been deacti-
vated in the sound system or MMI* settings).Note
•
Pressing the brake pedal will switch off the adaptive cruise
control system. The speed set at that point will, however, remain
stored until the adaptive cruise control is activated again.
•
To resume the programmed cruising speed, release the brake
pedal and pull the control lever towards you ⇒page 132,
“Switching off the system (with speed memory function) and reacti-
vating it”.
•
If you exceed the target speed by pressing the accelerator, the
driver intervention prompt will not be accompanied by a warning
tone. The indicator lamp shown in the display will also switch off
when the target speed is exceeded.
•
If the adaptive cruise control triggers a braking operation the
hydraulic brake system is under pressure. This is why brake pedal
travel will be shorter and the pedal will feel “harder”.
Applies to vehicles: with adaptive cruise controlSetting the warning tone volume and driving program
You can change the adaptive cruise control settings on
the sound system or MMI* to suit your individual driving
style.– Select: Function selector button > adaptive cruise
control.Setting the volume of the warning tone
If the adaptive cruise control system switches off (e.g. when the ESP
intervenes) or a driver intervention prompt appears, a warning tone
will sound.
You can set the volume of the warning tone to low, medium, or high.
The new volume will sound briefly after making any adjustment. If
you do not want a tone to sound, select off.
Adjusting the basic settings
You can set the distance (time interval) you want the adaptive cruise
control system to keep to the vehicle in front by selecting distance
1, distance 2, distance 3 or distance 4.
Fig. 148 Display: adap-
tive cruise control
CAR
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