Driving and operating189
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 operating193
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
3 197.
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.
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.
Detecting 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 3 197.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles ahead.
196Driving and operatingIf 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. 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 ifthe 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.
Hill and trailer considerations9 Warning
Do not use adaptive cruise control
on steep hill roads.
System performance on hills 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 you may have to
brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system.
198Driving and operatingA precondition is that forward collision
alert in the vehicle personalisation
menu is not deactivated 3 125.
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.
Simultaneously a warning chime
sounds. Depress the brake pedal and
steer the vehicle, if it is required by the
situation.
Selecting the alert sensitivity Press V or E to set the alert
sensitivity to near, medium or far.
Driving and operating199
The first button press shows the
current setting on the Driver
Information Centre. Additional button
presses will change this setting. The
chosen setting will remain until it is
changed. The alert timing will vary based on vehicle speed. The faster
the vehicle speed, the farther away
the alert will occur. Consider traffic
and weather conditions when
selecting the alert timing.Note that the alert timing sensitivity
setting is shared with the following
distance setting of the adaptive cruise
control. So changing the alert timing
sensitivity changes the adaptive
cruise control following distance
setting.
Deactivation
The system can be deactivated in the personalisation menu, 3 125.
If the forward collision alert was
deactivated, alert sensitivity is set to
"medium" when ignition is switched on next time.
The 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.
Driving and operating201● Weather limits visibility, such asfog, 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 3 197 or the Front pedestrian
protection alert 3 204.
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 53 mph.
With radar sensor active emergency
braking operates in forward gear
above walking speed at all speeds.
A precondition is that forward collision
alert with front camera system is not
deactivated in the vehicle
personalisation menu 3 125.
The system includes: ● brake preparation system
● emergency automatic braking ● forward looking brake assist
● intelligent brake assist (only with radar sensor)
● front pedestrian protection system
Brake preparation system
When approaching a vehicle ahead
or a pedestrian so quickly that a
collision is likely, the brake
preparation system slightly
pressurizes the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that braking can occur more rapidly.
If equipped only with front camera the
system operates up to a speed of 50
mph.
202Driving and operatingEmergency automatic braking
After activation of brake preparation
system and just before the imminent
collision, this function automatically
applies limited braking to reduce the
impact speed of the collision or
prohibit a crash. Depending on the
situation, the vehicle may
automatically brake moderately or
hard. This front automatic braking can
only occur if a vehicle ahead is
detected, indicated by the vehicle
ahead indicator A 3 197 . On vehicles
with front pedestrian protection, front automatic braking can also occur
when a pedestrian ahead is detected,
indicated by the pedestrian ahead
indicator 7.
If equipped only with front camera the system operates up to a speed of 50
mph.
Below a speed of 25 mph the system
can apply full braking.
Emergency automatic braking may
slow the vehicle to a complete stop to
try to avoid a potential crash. If this
happens, emergency automatic
braking may engage the electricparking brake to hold the vehicle at a stop. To release press the electric
parking brake button or firmly press
the accelerator pedal.9 Warning
Emergency automatic braking is
an emergency crash preparation
feature and is not designed to
avoid crashes. Do not rely on the
system to brake the vehicle.
Emergency automatic braking will
not brake outside of its operating speed range and only responds to
detected vehicles and
pedestrians.
Forward looking brake assist
In addition to the brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. Therefore, pressing
the brake pedal less strongly results
in immediate hard braking. This
function helps the driver brake
quicker and harder before the
imminent collision.
If equipped only with front camera the
system operates up to a speed of 53
mph.9 Warning
Active emergency braking is not
designed to apply hard
autonomous braking or to
automatically avoid a collision. It is designed to reduce the vehicle
speed before a collision. It may not
react to animals. After a sudden
lane change, the system needs a
certain time to detect the next
preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the brakes and steer to avoid
collisions.
The system is designed to work with
all occupants wearing their seat belts.
Intelligent Brake Assist
If the vehicle is equipped with radar
sensor Intelligent brake assist may
activate when the brake pedal is
Driving and operating203applied quickly by providing a boost
to braking based on the speed of
approach and distance to a vehicle
ahead.
Minor brake pedal pulsations or pedal
movement during this time is normal
and the brake pedal should continue
to be applied as needed. Intelligent
brake assist will automatically
disengage only when the brake pedal is released.9 Warning
Intelligent brake assist may
increase vehicle braking in
situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
Front pedestrian protection
3 204.
Deactivation
Active emergency braking can be
deactivated in the personalisation
menu 3 125. If deactivated a
message is displayed in the Driver
Information Centre.
System limitations In some cases, the active emergencybraking system may provide an
automatic braking in situations that
seem to be unnecessary, for instance
in parking garages, due to traffic signs
in a curve or due to vehicles in
another lane. This is normal
operation, the vehicle does not need service. Firmly apply the accelerator
pedal to override the automatic
braking if the situation and the
surroundings permit.
In the following cases, Active
emergency braking performance is limited:
● Driving on winding or hilly roads.
● Detecting all vehicles, especially vehicles with a trailer, tractors,
muddy vehicles, etc.● Detecting a vehicle when weather limits visibility, such as in
fog, rain, or snow.
● 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.
To avoid malfunction keep the areas
of the camera sensor in the
windscreen and the radar sensor in
the radiator grille always clean from
dirt, dust, ice and snow.
Complete attention is always required
while driving, and you should be ready to take action and apply the
brakes and/or steer the vehicle to
avoid crashes.
Fault
In case the system requires a service,
a message is displayed in the Driver
Information Centre.