
Driving123
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
braking force of the parking brake is only released when there is
enough power at the wheels to make the vehicle move in the desired
direction.
Note
For safety reasons the parking brake will only release automatically
if the driver's seat belt
is engaged in its buckle.Driving away when towing a trailer
Please note the following po ints to prevent the vehicle
from rolling back unintentionally on a gradient.– Pull and hold the parking brake switch and press the
accelerator. The parking brake will remain engaged and
prevent any tendency to roll back down the slope.
– You can release the parking brake switch as soon as the engine is delivering enough power to the wheels.Depending on the weight of the vehicle and trailer and the steep-
ness of the slope, there may be a tendency to roll back downhill
when driving away from a standstill. You can prevent this by pulling
out the parking brake switch as you press the accelerator (in the
same way as with a conventional handbrake).Emergency braking function
This feature enables you to stop the vehicle if the main
brake system should fail or if the pedal is obstructed.– Pull out and hold the parkin g brake switch to stop the
vehicle with the parking brake in an emergency.
– The brakes will be released immediately if you release the switch or press down the accelerator.
If you pull out and hold the park ing brake switch at a road speed
above about 8 km/h, this will initiate an emergency brake applica-
tion. The brakes are then applied hy draulically at all four wheels.
The effect is the same as an emergency stop (full brake application)
⇒
To prevent the emergency braking function from being used acci-
dentally, a warning buzzer sounds when the switch is operated. The
brakes are released immediately when you release the switch or
press down the accelerator.
WARNING
You should only use the emergency braking function in a real
emergency, for example if the brake system should fail or if the
brake pedal is obstructed. If you use the emergency braking func-
tion by activating the parking brak e switch, the effect is similar to
a full brake application (emergenc y stop). Please remember that
the ESP (with its combined ABS, EDL and traction control func-
tions) is still subject to certain physical limits. In a corner or in bad
road or weather conditions an emergency stop can cause the
vehicle to skid or lose steering control.Driver messages in the instrument cluster displayCaution: Vehicle parked too steep
This message can appear when you apply the parking brake if the
car is parked on a gradient steeper than about 30%.
In this case the parking brake may not be strong enough to prevent
the vehicle from rolling back accidentally.
Please release parking brake
However, please remember that, for safety reasons, the parking
brake will only release automatically if the driver's seat belt is
buckled.
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adaptive cruise control (ACC)
128adaptive cruise control (ACC)Speed and distance control systemApplies to vehicles: with adaptive cruise controlDescription
The adaptive cruise control is a combined speed and
distance control system to assist the driver.Adaptive cruise control allows you to maintain any desired constant
speed between 30 and 200 km/h. In addition, the system controls
the distance maintained to the vehicle in front (subject to certain
limitations as described below).
The system can be used to greatest effect on long motorway jour-
neys or on other main roads with long straight sections.
How is the system operated?
The adaptive cruise control system is operated via a control lever on
the steering wheel ⇒page 131, “Setting the speed” and
⇒ page 133, “Setting the distance”. Driver messages
When the system is being used, important information is displayed
in the speedometer and on the instrument cluster display screen
⇒
page 134, “Driver messages”.
Please note the following points:
The adaptive cruise control has ce rtain limits determined by the
system itself. This means that the driver may in some situations
have to intervene and control the speed and distance to the vehicle
in front himself ⇒page 138, “Driver intervention prompt” and
⇒ page 140, “System limitations”.
WARNING
Please always direct yo ur full attention to the road, even when you
are using adaptive cruise control. It is always the driver who is
responsible for determining the speed and for keeping a safe
distance to the other vehicles on the road.•
For safety reasons, the adaptive cruise control must not be
used in city traffic, stop-go traffic, roads with a lot of bends or in
difficult driving condition s (such as ice, fog, loose grit or gravel,
heavy rain, aquaplaning) - this could cause an accident!
•
When you take a turn-off, drive along a motorway exit lane or
pass through roadwork sections, please temporarily switch off the
adaptive cruise control in order to avoid the vehicle accelerating to
the selected speed.
•
The adaptive cruise control can only control the distance to
vehicles in front. As a rule, it cannot recognize vehicles travelling
in other lanes. For this reason, please temporarily switch off the
system if you are travelling in th e inside lane and vehicles in the
overtaking lane are travelling at a slower speed than you are.
Otherwise, you would overtake these vehicles on the inside.
Fig. 136 Trim grille
(front right): Position of
radar sensor
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adaptive cruise control (ACC)129
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
Adaptive cruise control will not react when approaching a
stationary obstacle, e.g. the end of a traffic jam or a broken-down
vehicle, or if a vehicle should come towards you in the same lane.
•
Please make sure you do not unintentionally rest your foot on
the accelerator - this will override the adaptive cruise control
system which, as a result, will not automatically brake the vehicle.Note
•
For safety reasons, the speed setting will be deleted when the
ignition is switched off.
•
Switching on the adaptive cruise control automatically activates
the Electronic Stabilisation Program (ESP) and the traction control
system (ASR). These two systems cannot be deactivated while the
adaptive cruise control is switched on.
•
Damage caused by impacts (e.g. if the vehicle is damaged when
parking) can affect the radar sensor settings. This can cause the
system to malfunction or switch off completely.
•
The radar sensor is heated. However, in winter conditions, you
should make sure that the radar sensor is free of ice and snow
before you set off. If necessary, carefully clean the cover of the radar
sensor and the surrounding area ⇒page 128, fig. 136.
•
To make sure that the radar sensor is fully operative, do not
attach any objects (e.g. stickers, add-on parts or other accessories)
to the area surrounding the radar sensor. Do not paint the area
surrounding the radar sensor.
Applies to vehicles: with adaptive cruise control and manual gearboxVehicles with manual gearbox
The driver of a vehicle with a manual gearbox of course
has to change gears as appropriate, even when the adap-
tive cruise control is activated.The adaptive cruise control is available from the second to the sixth
gear (when driven in normal engine speed range).
When the adaptive cruise control is activated, the driver must press
the clutch pedal as normal in order to change gear. When changing
gear or pressing the clutch pedal (for up to 20 seconds), the adap-
tive cruise control will remain activated.
When changing gear, the driver does not have to accelerate after
engaging a gear as the engine torque will be coordinated by the
adaptive cruise control.
The following situations may lead to an automatic deactivation of
the adaptive cruise control :•
pressing the clutch pedal too long (longer than approx.
20 seconds)
•
incorrect changing of gears and/or use of the clutch pedalNote
•
The adaptive cruise control cannot be activated while changing
gears.
WARNING (continued)
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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 driv ing 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 ad apt 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 wi ll 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 sy stem 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)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)
134
WARNING
When setting the distance, the driv er is responsible for adhering
to the laws and regulations which apply in the country he is trav-
elling in.Driver messagesApplies to vehicles: with adaptive cruise controlMessages in the instrument cluster
The instrument cluster displa ys various driver messages.Fig. 143 Overview of instrument cluster
Indicator lamp and speedometer display
Instrument cluster display
System status indicator Indicator lamp and speedometer display
Section of the display shows important information regarding
the use of the adaptive cruise control system. The target speed you
have set is marked by diodes in the speedometer.
The indicator lamp shows whether the system has detected a
vehicle in front.
Instrument cluster display
You can call up the display for the adaptive cruise control by repeat-
edly pressing the button on the windscreen wiper lever. For
more details refer to ⇒ page 27.
System status indicator
The information in section of the display is not shown perma-
nently. It only appears if you, for example, set or change the speed
setting, change the time interval, when messages are displayed, or
if the adaptive cruise control is switched off for safety reasons.
Applies to vehicles: with adaptive cruise controlIndicator lamp and display in the speedometer
AAABAC
AA
AA
AB
RESET
AC
AC
Fig. 144 Instrument
cluster: Indicator lamp
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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 crui se 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 driv er 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 sy stem* 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)
136•
Vehicle in front: If a vehicle is detected in front, the arrows will be
on the scale. The green area of the scale represents the distance
setting. If you approach the vehicle in front slowly, the arrows will
move from the grey area into the green area of the scale.
•
Driver intervention prompt: If you approach the vehicle in front
quickly, the arrows act as a warnin g. When the actual distance is
shorter (or is likely to become shorter) than the distance selected,
the arrows move into the red area of the scale. In certain situations,
you may need to intervene as the driver ⇒page 138, “Driver inter-
vention prompt”.
Status
•
ACC OFF (in white letters): The adaptive cruise control is
switched off.
•
ACC AVAILABLE (in white letters): The system is switched on but
the control has not yet been activated.
•
OVERRIDE (in white letters): You have exceeded the target speed
by accelerating.
•
DISTANCE! (in red letters): The distance to the vehicle in front is
not sufficient and you have to brak e the vehicle with the foot brake.
•
DISTANCE 1 to DISTANCE 4 (in green letters): Shows the time
interval you have selected. The adap tive cruise control is in cruise
mode.
•
DISTANCE 1 - dyn. , DISTANCE 1 - comf. etc. (in green letters): If
the settings are adjust ed on the sound system or MMI* such that
the “standard” driving program is replaced by “comfort” or
“dynamic”, the message above will indicate the setting.
Applies to vehicles: with adaptive cruise controlSystem status indicator in the instrument cluster display
The text messages and symbols in this section of the
display are not shown permanently.Time intervals (e.g.
)
The various symbols for the time intervals -arrow- ⇒fig. 146 appear
when you change the settings.
The symbol
indicates that the warning tone has been switched
off.
...
The text message ... (three white dots) appears if a setting made
with the control lever cannot be implemented. There can be several
reasons for this:
•
You have pulled the control lever towards you to resume the
programmed cruising speed, without a target speed having been
set.
•
The control lever has been pushed up / down to increase / reduce
the speed, without a target speed having been set.
AC
Fig. 146 Instrument
cluster: Further infor-
mation
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