Driving and operating181
Switching off
Press button m, control indicator m in
instrument cluster extinguishes. The
stored speed is deleted.
Pressing button L for activating
speed limiter or switching off the
ignition also switches off cruise
control and deletes the stored speed.
Speed limiterThe speed limiter prevents the
vehicle exceeding a preset maximum
speed.
The maximum speed can be set at a
speed above 25 km/h.
The driver can only accelerate up to
the preset speed. Deviations from the
limited speed may occur when driving downhill.
The preset speed limit is displayed in
the top line of the Driver Information
Centre when the system is active.Activation
Press button L. If cruise control or
adaptive cruise control has been
activated before, it is switched off
when speed limiter is activated and
the control indicator m extinguishes.
Set speed limit
With speed limiter active, hold thumb
wheel turned to RES/+ or briefly turn
to RES/+ repeatedly until the desired
maximum speed is displayed in the
Driver Information Centre.
Alternatively accelerate to the desired speed and briefly turn thumb wheel to SET/- : the current speed is stored as
maximum speed. Speed limit is
displayed in the Driver Information
Centre.
Change speed limit
With speed limiter active, turn thumb
wheel to RES/+ to increase or SET/-
to decrease the desired maximum
speed.
Exceeding the speed limit
In the event of an emergency it is possible to exceed the speed limit by
depressing the accelerator pedal
firmly beyond the point of resistance.
182Driving and operating
The limited speed will flash in the
Driver Information Centre and a
chime sounds during this period.
Release the accelerator pedal and the speed limiter function is
reactivated once a speed lower than
the limit speed is obtained.
Deactivation
Press button y: speed limiter is
deactivated and the vehicle can be
driven without speed limit.
The limited speed is stored and a
corresponding message appears in
the Driver Information Centre.
Resume limit speed
Turn thumb wheel to RES/+. The
stored speed limit will be obtained.
Switching off
Press button L, the speed limit
indication in the Driver Information
Centre extinguishes. The stored
speed is deleted.By pressing button m to activate
cruise control or adaptive cruise
control or by switching off the ignition,
speed limiter is also deactivated and
the stored speed is deleted.
Adaptive cruise control
Adaptive cruise control is an
enhancement to traditional cruise
control with the additional feature of maintaining a certain distance behind the vehicle ahead.
Adaptive cruise control automatically
decelerates the vehicle when
approaching a slower moving vehicle. It then adjusts the vehicle speed to
follow the vehicle ahead at the
selected following distance. The
vehicle speed increases or decreases to follow the vehicle in front, but willnot exceed the set speed. It may
apply limited braking with activated
brake lights.
The adaptive cruise control can store
and maintain speeds over approx.
50 km/h and brakes automatically tofollow a slower vehicle driving ahead
down to a minimum speed of
30 km/h.
Adaptive cruise control uses a radar
sensor to detect the vehicles ahead.
If no vehicle is detected in the driving
path, the adaptive cruise control will
behave like a traditional cruise
control.
For safety reasons, the system
cannot be activated before the brake
pedal has been depressed once after
switching on ignition. Activation in first gear is not possible.
Adaptive cruise control is mainly
advised to be used on long straight
roads, e.g. highways or country roads
with steady traffic. Do not use the
system if it is not advisable to
maintain a constant speed.
Control indicator A 3 116, m 3 116.
Driving and operating1839Warning
The complete driver attention is
always required while driving with adaptive cruise control. The driver stays fully in control of the vehicle
because the brake pedal, the
accelerator pedal and the cancel
switch have priority over any
adaptive cruise control operation.
Switching on
Press button C to switch on adaptive
cruise control. The control indicator
m illuminates white.
Activation by setting the speed
Adaptive cruise control can be
activated between 50 km/h and
180 km/h.
Accelerate to the desired speed and
turn thumb wheel to SET/-; the
current speed is stored and
maintained. Control indicator m
illuminates green.
The adaptive cruise control symbol,
the following distance setting and set speed are indicated in the top line ofthe Driver Information Centre.
The accelerator pedal can be
released. Adaptive cruise control
remains activated while gearshifting.
Overriding set speed
It is always possible to drive faster than the selected set speed by
depressing the accelerator pedal.
When the accelerator pedal is
released, the vehicle returns to the
desired distance if a slower vehicle is ahead. Otherwise it returns to the
stored speed.
184Driving and operating
Once the system is activated,
adaptive cruise control decelerates or
brakes if it detects a vehicle ahead
which is slower or closer than the
desired following distance.9 Warning
Accelerating by the driver
deactivates automatic braking by
the system. This is indicated as a
pop-up warning in the Driver
Information Centre.
Increase speed
With adaptive cruise control active,
hold thumb wheel turned to RES/+:
speed increases continuously in large increments, or activate repeatedly
RES/+ : speed increases in small
increments.
If the vehicle is driven with adaptive cruise control active much faster than
the desired speed, e.g. after
depressing the accelerator pedal,
then the current speed can be stored and maintained by turning the thumb
wheel to SET/-.
Reduce speed
With adaptive cruise control active,
hold thumb wheel turned to SET/-:
speed decreases continuously in
large increments, or activate
repeatedly SET/-: speed decreases in
small increments.
With adaptive cruise control active, if
the vehicle is driven much slower than
the desired speed, e.g. because of a
slower vehicle ahead, then the
current speed can be stored and
maintained by turning the thumb
wheel to SET/-.
Resume stored speed
If the system is switched on but
inactive, then turn thumb wheel to
RES/+ at a speed above 50 km/h to
resume the stored speed.
Setting the following distance
When adaptive cruise control detects a slower moving vehicle in the drivingpath, it will adjust the vehicle speed to
maintain the following distance
selected by the driver.The following distance can be set to
near, medium or far.
Press button E, the current setting is
shown on the Driver Information
Centre. Press button E again to
change the following distance. The
setting is also displayed in the top line
of the Driver Information Centre.
Driving and operating185
The selected following distance is
indicated by filled distance bars on
the adaptive cruise control page.
Note that the following distance
setting is shared with the sensitivity
setting of forward collision alert.
Example: If setting 3 (far) is selected,
then the driver is warned sooner
before a possible collision, also if
adaptive cruise control is inactive or
switched off.
9 Warning
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
Following distance must be
adjusted or the system switched
off when required by the prevailing
conditions.
Detecting the vehicle ahead
The green illuminated "vehicle
ahead" control indicator A is
displayed in the speedometer when the system detects a vehicle in the
driving path.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles
ahead.
Deactivation
Adaptive cruise control is deactivated by the driver when:
■ button y is pressed,
■ brake pedal is applied,
■ clutch pedal is depressed for more than four seconds,
■ gear selector lever of automatic transmission is moved to N.
The system is also automatically
deactivated when:
■ vehicle speed slows down below 45 km/h or accelerates above
190 km/h,
■ Traction Control system is operating for more than
20 seconds,
186Driving and operating
■ Electronic Stability Control isoperating,
■ there is no traffic and nothing detected on the road sides for
several minutes. In this case there are no radar echoes and the sensor may report that it is blocked,
■ collision imminent braking system is applying the brakes,
■ radar sensor is blocked by an ice or
water film,
■ fault is detected in the radar, engine
or brake system.
When adaptive cruise control is
deactivated automatically, the control
indicator m illuminates white and a
warning symbol is displayed as a pop- up in the Driver Information Centre.
The stored speed is maintained.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press button C to switch off adaptive
cruise control. The control indicator
m extinguishes. The stored speed is
deleted.
Switching off the ignition also
switches off adaptive cruise control
and deletes the stored speed.
Driver's attention
■ Use adaptive cruise control carefully on bends or mountain
roads, as it can lose the vehicle
ahead and require time to detect it
again.
■ Do not use the system on slippery roads as it can create rapid
changes in tyre traction (wheel
spinning), so that you could lose
control.
■ Do not use adaptive cruise control during rain, snow or heavy dirt, as
the radar sensor can be covered by a water film, dust, ice or snow. This
reduces or completely suppresses
the visibility. In case of sensor
blockage, clean the sensor cover.
System limits ■ The system's automatic brake force
does not permit hard braking and
the braking level may not be
sufficient to avoid a collision.
■ After a sudden lane change, the system needs a certain time todetect the next preceding vehicle.
Driving and operating187
So if a new vehicle is detected, the
system may accelerate instead of
braking.
■ Adaptive cruise control does ignore
the oncoming traffic.
■ Adaptive cruise control does not brake for stopped vehicles,
pedestrians or animals.
Bends
The adaptive cruise control calculates
a predicted path based on the
centrifugal force. This predicted path
considers the current bend
characteristic, but cannot consider a
future bend change. The system may lose the current vehicle ahead or
consider a vehicle which is not in the
actual lane. This can happen when
entering or exiting a bend or if the
bend gets stronger or weaker. If it no
longer detects any vehicle ahead,
then control indicator A will
extinguish.
If the centrifugal force is too high in a bend, the system slows down the vehicle slightly. This braking level is
not designed to avoid spinning off the bend. The driver is responsible for
reducing the selected speed before
entering a bend and in general to
adapt the speed to the road type and
to existing speed limits.
Motorways
On motorways, adapt the set speed
to the situation and the weather.
Always consider that adaptive cruise
control has a limited visibility range, a
limited braking level and a certain
reaction time to verify if a vehicle is in
the driving path or not. Adaptive
cruise control may not be able to
brake the vehicle in time to avoid a
collision with a much slower vehicle or after a lane change. This is
particularly true if driving fast or if the
visibility is reduced due to weather
conditions.
While entering or exiting a motorway,
adaptive cruise control may lose the
vehicle ahead and accelerate up to
the set speed. For this reason,
decrease the set speed before the
exit or before the entry.
Vehicle path changes
If another vehicle enters your driving
path, adaptive cruise control will first
consider the vehicle when it is
completely in your path. Be ready to
take action and depress the brake
pedal, if you need to brake more
quickly.
188Driving and operating
Hill and trailer considerations
System performance on hills and
when towing a trailer depends on
vehicle speed, vehicle load, traffic
conditions and the road gradient. It
may not detect a vehicle in your path
while driving on hills. On steep hills,
you may have to use the accelerator
pedal to maintain your vehicle speed.
When going downhill, especially
when towing a trailer, you may have
to brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system. It is not
recommended to use adaptive cruise
control on steep hills especially when towing a trailer.
Radar unit
The radar unit is mounted behind the
radiator grille below the brand
emblem.
9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, after a frontal accident, do not use the system. The front
bumper may appear to be intact,
however the sensor behind can be
out of position and react
incorrectly. After an accident,
consult a workshop to verify and
correct the adaptive cruise control
sensor position.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation 3 130.
Fault
If the adaptive cruise control does not
work due to temporary conditions
(e.g. blockage by ice) or if there is a
permanent system error, then a
message is displayed in the Driver
Information Centre.