190Driving and operating
On Mid- and Uplevel display L
changes to green.
Change speed limit With speed limiter active, hold or
briefly turn thumb wheel to RES/+ to
increase or SET/- to decrease the
desired maximum speed.
Exceeding the speed limit
When exceeding the limited speed without driver input, the speed will
flash in the Driver Information Centre
and a chime sounds during this
period.
In the event of an emergency, it is
possible to exceed the speed limit by
depressing the accelerator pedal
firmly nearly to the final point. In this
case no chime appears.
Release the accelerator pedal and
the speed limiter function is
reactivated once a speed lower than
the limit speed is obtained.
Deactivation Press y: speed limiter is deactivated
and the vehicle can be driven without
speed limit.
On Baselevel display the stored
limited speed is indicated in brackets.
On Mid- or Uplevel display L
changes to white.
Additionally, a corresponding
message appears.
Speed limiter is deactivated, but not
switched off. Last stored speed
remains in memory for later speed
resume.
Resume limit speed
Turn thumb wheel to RES/+. The
stored speed limit will be obtained
and is indicated without brackets in
the Driver Information Centre.
Switching off
Press L, the speed limit indication
extinguishes in the Driver Information Centre. The stored speed is deleted.
By pressing m to activate cruise
control or adaptive cruise control, speed limiter is also deactivated and
the stored speed is deleted.
By switching off the ignition, speed
limiter is also deactivated, but the
speed limit will be stored for next
speed limiter activation.
Adaptive cruise control
Adaptive cruise control is an
enhancement to conventional cruise control with the additional feature ofmaintaining a certain distance behind the vehicle ahead.
Driving and operating191Adaptive 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.
To facilitate overtaking a vehicle on
the motorway, the activation of the
turn signal reduces the following
distance for a short time. This function is implemented only on the respective
driver's side depending on left or right
hand drive vehicle configuration.
The adaptive cruise control can store
set speed over 30 km/h for manual
transmission. On vehicles with
automatic transmissions the system
can brake until a full stop and drive off from a stop.
Adaptive cruise control uses radar
and camera sensors to detect the
vehicles ahead. If no vehicle is
detected in the driving path, the
adaptive cruise control will behave
like a conventional cruise control.
Adaptive cruise control is mainly
advised to be used on long straight
roads like 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 3 112, C 3 112.
9 Warning
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
Illustrations show different versions.
194Driving and operatingPress E, the current setting is shown
in the Driver Information Centre.
Press E again to change the
following distance. The setting is also displayed in the Driver Information
Centre.
The selected following distance is
indicated by filled distance bars in the
adaptive cruise control page.
Note that the following distance
setting is shared with the sensitivity
setting of forward collision alert
3 198.
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 to drive with the
appropriate following distance
based on traffic, weather, visibility
and regional regulation. Followingdistance must be adjusted or the
system switched off when required by the prevailing conditions.
Adaptive cruise control in Sport
mode
On vehicles with Flex Ride driving
modes, the driver can slightly
increase the Adaptive cruise control
acceleration when Sport mode is
selected. This function can be
deactivated in the Flex Ride
visualisation menu 3 184
Driving and operating195Detecting the vehicle ahead
The green illuminated vehicle ahead
control indicator A is displayed when
the system detects a vehicle in the driving path. The range of the sensors
is between 25 and 150 metres
depending on vehicle speed.
Forward collision alert 3 198.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles ahead.
Deactivation Adaptive cruise control is deactivatedby the driver when:
● y is pressed.
● Brake pedal is applied.
● Clutch pedal is depressed for more than four seconds.
● Selector lever of automatic transmission is moved to N.
The system is also automatically deactivated when:
● Vehicle speed accelerates above
190 km/h or slows down below
25 km/h, on vehicles with
automatic transmission it slows
down to a stop without
deactivating within five minutes.
● The Traction Control system is deactivated or operating.
● The Electronic Stability Control is
deactivated or operating.
● There is no traffic and nothing detected on the road sides forapprox. one minute. In this casethere are no radar echoes and
the sensor may report that it is
blocked.
● The active emergency braking system is applying the brakes.
● Driving on steep inclines.
● The radar sensor is blocked by an ice or water film.● A fault is detected in the radar,camera, engine or brake system.
● The brakes need to cool down.
Additionally, the system is
automatically deactivated on vehicles
with automatic transmission (full
speed range adaptive cruise control)
when:
● The incline uphill or downhill is greater than 20 %.
● The electric parking brake is applied.
● The vehicle is being held to a stop
by the system for more than
five minutes.
● The vehicle stops, the driver's seat belt is unbuckled and thedriver's door is opened.
When adaptive cruise control is
deactivated, the control indicator m
changes from green to white and a
pop-up message is displayed in the
Driver Information Centre.
The stored speed is maintained.
Driving and operating197● Do not use adaptive cruisecontrol when towing a trailer.
● Do not use adaptive cruise control on roads with an incline ofmore than 10%.
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. The
camera applies a certain correction
based on the detectable lane
markings. The control indicator A will
extinguish, if a vehicle ahead is no longer detected.
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 on
the driving path or not. Furthermore,
Adaptive cruise control was designed to brake as late as possible to allow
changing the lane before the
automatic braking. 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 while
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.
Driving and operating199If the vehicle is equipped with
conventional cruise control, the
forward collision alert uses the front
camera in the windscreen to detect a
vehicle directly ahead, in your path.
If the vehicle is equipped with
adaptive cruise control, the forward
collision alert uses the radar sensor
and front camera to detect a vehicle
directly ahead, in your path.
A vehicle ahead is indicated by the
control indicator A.
If a vehicle directly ahead is
approached too quickly, a warning
chime and alert in the Driver
Information Centre is provided.
Additionally the driver gets notified by
a flashing red LED stripe or a pop up
symbol in the head-up display which
is projected on the windscreen in the
driver's field of view.
A precondition is that forward collision
alert in the vehicle personalisation
menu is not deactivated 3 126.
Activation
Forward collision alert with front
camera detects vehicles to distances
of approximately 60 metres and
operates automatically at all speeds
above walking speed.
Forward collision alert with radar
sensor detects vehicles to distances
of approximately 150 metres and
operates automatically at all speeds
above walking speed.
Alerting the driver The vehicle ahead control indicator
A illuminates green in the instrument
cluster when the system has detected
a vehicle in the driving path. On
vehicles with head-up display, A is
projected on the windscreen.
The control indicator A changes to
yellow when the distance to a
preceding moving vehicle gets too
small.Caution
The colour lighting of this control
indicator does not correspond to
local traffic laws on following
distance. The driver bears full
responsibility for maintaining safe
following distance according to
applicable traffic rules, weather
and road conditions etc. at all
times.
When the time to a potential collision
with a vehicle in front gets too small
and a collision is imminent, the
collision alert symbol pops-up in the
Driver Information Centre and the
driver gets notified by a flashing red
LED stripe or the pop-up symbol in
the head-up display which is
projected on the windscreen in the
driver's field of view.
Driving and operating201The last selected setting will be stored
when the ignition is switched off.
General information9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
System limitations
Forward collision alert is designed to warn on vehicles only, but may reactalso to other objects.
In the following cases, Forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
● Driving on winding or hilly roads.● During nighttime driving.
● Weather limits visibility, such as fog, rain, or snow
● The sensor in the windscreen is blocked by snow, ice, slush, mud,dirt, windscreen damage or
affected by foreign items, e.g.
stickers.
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The front camera in
the windscreen is used to detect the
distance of a vehicle directly ahead in
the vehicle's path. It is active at
speeds above 40 km/h.
When a preceding vehicle is detected ahead, the distance is indicated inseconds, displayed on a page in the
Driver Information Centre.On Baselevel display, choose Info
Menu ? via MENU on the turn
signal lever and turn the adjuster
wheel to choose following distance
indication page, 3 113
On Mid- and Uplevel display, select
Info menu via steering wheel buttons
and press å to select following
distance indication 3 113.
The minimum indicated distance is 0.5 seconds.
If there is no vehicle ahead or the vehicle ahead is out of range, two
dashes will be displayed: -.- sec.
202Driving and operating
If Adaptive cruise control is active,
this page shows the alert sensitivity
setting instead of following distance setting. 3 190.
System limitations In the following cases, following
distance indication sensor
performance is limited:
● Driving on winding or hilly roads.● During nighttime driving.
● Weather limits visibility, such as fog, rain, or snow.
● The sensor is blocked by snow, ice, slush, mud, dirt, windscreen
damage or affected by foreign
items, e.g. stickers.
Active emergency braking Active emergency braking can help toreduce the damage and injury from
crashes with vehicles, pedestrians and obstacles directly ahead, when a
collision can no longer be avoided
either by manual braking or by
steering. Before the active
emergency braking applies, the driver
is warned by the Forward collision
alert 3 198 or the Front pedestrian
protection alert 3 205.
The feature uses various inputs (e.g.
camera sensor, radar sensor, brake
pressure, vehicle speed) to calculate
the probability of a frontal collision.9 Warning
This system is not intended to
replace the driver responsibility for driving the vehicle and looking
ahead. Its function is limited to
supplemental use only to reduce
the vehicle speed before a
collision.
The system may not react to
animals. After a sudden lane
change, the system needs a
certain time to detect the next
preceding vehicle.
The driver must always be ready
to take action and apply the brakes and steer to avoid collisions.
Functionality
If equipped only with front camera the
active emergency braking operates in forward gear above walking speed up
to 85 km/h.
With radar sensor active emergency
braking operates in forward gear
above walking speed at all speeds.