184Driving and operatingIn the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
● on winding roads
● when weather limits visibility, such as fog, rain, or snow
● when the sensor 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 25 mph.
When a preceding vehicle is detected
ahead, the distance is indicated in
seconds, displayed on a page in the
Driver Information Centre.On Midlevel 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 Uplevel display, select Info menu
via steering wheel buttons and press o 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.
Active emergency braking
Active emergency braking can help toreduce the damage and injury from
crashes with vehicles 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 3 181.
The feature uses various inputs (e.g.
camera sensor, brake pressure,
vehicle speed) to calculate the
probability of a frontal collision.
Active emergency braking operates
above walking speed up to 53 mph. A precondition is that the system is not
deactivated by toggling the gap
switch V to Off setting, 3 181.
The system includes: ● brake preparation system
● emergency automatic braking ● forward looking brake assist
Driving and operating1859Warning
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. The driver must continue to apply the brake
pedal as the driving situation
dictates.
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the
brake preparation system slightly
pressurises 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.
The system operates up to a speed of 50 mph.
Emergency automatic braking
After the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of the collision or prohibit a crash.
The system operates up to a speed of 37 mph.
Below a speed of 25 mph the system
can apply full braking.
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,
depressing the brake pedal less
strongly results in immediate hard
braking. This function helps the driver
brake quicker and harder before the
imminent collision.
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 for pedestrians or 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 shall always be ready to take action and apply the
brakes and steer to avoid
collisions. The system is designed to work with all occupants wearingtheir seat belts.
System limitations
The active emergency braking has
limited or no function during rain,
snow or heavy dirt, as the camera
sensor can be covered by a water
film, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
186Driving and operatingIn 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.
Deactivation
Active emergency braking can be
deactivated by repeatedly pressing
the gap switch V to Off setting,
3 181. If deactivated a message is
displayed in the Driver Information
Centre.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
If the system does not work as it
should do, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 120.
Parking assist Rear parking assist9 Warning
It is the driver who bears full
responsibility for the parking
manoeuvre.
Always check the surrounding
area while reversing and using the rear parking assist system.
The rear parking assist makes
parking easier by measuring the
distance between the vehicle and
rear obstacles. It informs and warns
the driver by giving acoustic signals
and display indication.
The system has four ultrasonic
parking sensors in the rear bumper.
Activation
After ignition is switched on, the rear
parking assist is activated.
An illuminated LED in the parking
assist button r indicates that the
system is ready to operate.
188Driving and operating
The system has four ultrasonic
parking sensors each in the rear and
front bumper.
Activation
The system is activated automatically
at a speed up to 7 mph.An illuminated LED in the parking
assist button r indicates that the
system is ready to operate.
If r is switched off within an ignition
cycle, the front parking assist is
deactivated. If vehicle speed has
exceeded 15 mph beforehand,
parking assist will be reactivated when speed drops below 7 mph.
When the system is deactivated, the
LED in the button extinguishes and
Park Assist Off pops-up in the Driver
Information Centre.
Indication
The system warns the driver with
acoustic signals against potentially
hazardous obstacles in front of the
vehicle in a distance range up to 80
cm and against potentially hazardous
obstacles behind the vehicle in a
distance range up to 50 cm while a
forward gear is engaged, respectively up to 1.5 m while reverse gear is
engaged.
Depending on which side of the
vehicle is closer to an obstacle, you
will hear acoustic warning signals inthe vehicle on the respective side.
The interval between the sounds
becomes shorter as the vehicle gets
closer to that obstacle. When the
distance is less than approx. 30 cm,
the sound is continuous.
Additionally, the distance to rear and
front obstacles is displayed by
changing distance lines in the Driver
Information Centre 3 113 or,
depending on the version, on the Info-
Display 3 118.
190Driving and operating
Advanced parking assist is always
combined with front-rear parking assist. Both systems use the same
sensors in the front and rear bumper.
The system has six ultrasonic parking sensors each in both the rear and
front bumper.
Activation of advanced parking assist
Advanced parking assist can only be
activated when driving forwards.When searching for a parking slot, the system is ready to operate with a
short press of (.
The system recognises and
memorises ten metres for parallel parking slots or six metres for
perpendicular parking slots in the
parking assist mode.
The system can only be activated at
a speed up to 18 mph and the system searches for a parking slot at a speed
up to 18 mph.
The maximum allowed parallel
distance between the vehicle and a
row of parked cars is 1.8 metres for parallel parking and 2.5 metres for
perpendicular parking.
FunctionalityParking slot searching mode,
indication in the Driver Information
Centre
Select parallel or perpendicular
parking slot in Driver Information
Centre by long press on (.
The system is configured to detect parking slots by default on the
passenger side. To detect parking
slots on the driver side, switch on turn
signal indicator on the driver side.
Driving and operating193Fault
A message appears when:
● There is a fault in the system.● The driver did not successfully complete the parking
manoeuvre.
● The system is not operational.
● Any of the deactivation reasons described above apply.
If an object is detected during parking
instructions, Stop is indicated on the
display. Removing the object will
resume the parking manoeuvre. If the
object is not removed, the system will be deactivated. A long press of ( will
activate the system and search for a
new parking slot.
Basic notes on parking assist
systems9 Warning
Under certain circumstances,
various reflective surfaces on
objects or clothing as well as
external noise sources may cause the system to fail to detect
obstacles.
Special attention must be paid to
low obstacles which can damage
the lower part of the bumper.Caution
Performance of the system can be reduced when sensors are
covered, e.g. by ice or snow.
Performance of the parking assist
system can be reduced due to
heavy loading.
Special conditions apply if there
are taller vehicles in the vicinity
(e.g. off-road vehicles, mini vans,
vans). Object identification and correct distance indication in the
upper part of these vehicles
cannot be guaranteed.
Objects with a very small reflection
cross-section, e.g. objects of
narrow size or soft materials, may
not be detected by the system.
Parking assist systems do not
detect objects outside the
detection range.
Notice
It is possible that the sensor detects a non-existing object caused by
echo disturbance from external
acoustic noise or mechanical
misalignments (sporadic false
warnings may occur).
Make sure that the front number
plate is properly mounted (not bent
and no gaps to the bumper on the left
or right side) and the sensors are
firmly in place.
Advanced parking assist system
may not respond to changes in the
available parking space after
initiating a parking manoeuvre. The
system may recognize an entry, a
gateway, a courtyard or even a crossing as a parking slot. After
selecting reverse gear the system
194Driving and operatingwill start a parking manoeuvre. Takecare regarding the availability of the
suggested parking slot.
Surface irregularities, e.g. on
construction zones, are not detected
by the system. The driver accepts
responsibility.
Notice
After production, the system requires a calibration. For optimal parking guidance, a driving distance
of at least 6 miles, including a
number of bends, is required.
Side blind spot alert
The Side blind spot alert system
detects and reports objects on either
side of the vehicle, within a specified
"blind spot" zone. The system alerts
visually in each exterior mirror, when
detecting objects that may not be
visible in the interior and exterior
mirrors.
Side blind spot alert uses some of the advanced parking assist sensors
which are located in the front and rear
bumper on both sides of the vehicle.9 Warning
Side blind spot alert does not
replace driver vision.
The system does not detect:
● vehicles outside the side blind zones which may be rapidly
approaching
● pedestrians, cyclists or animals
Before changing a lane, always
check all mirrors, look over the
shoulder and use the turn signal.
When the system detects a vehicle in the side blind zone while driving
forwards, either while passing a
vehicle or being passed, a yellow
warning symbol B will illuminate in
the relevant exterior mirror. If the
driver then activates the turn signal,
the warning symbol B starts flashing
yellow as a warning not to change
lanes.
Notice
If the overtaking vehicle is at least
6 mph faster than the vehicle being
overtaken, the warning symbol B in
the relevant exterior mirror may not
illuminate.
Side blind spot alert is active from
speeds of 6 mph up to 87 mph.
Driving faster than 87 mph
deactivates the system, indicated by
low lighting warning symbols B in
both exterior mirrors. Reducing the speed again will extinguish the
warning symbols. If a vehicle is then
detected in the blind zone, the
warning symbols B will illuminate as
normal on the relevant side.
Driving and operating195When the vehicle is started, both
exterior mirror displays will briefly
come on to indicate that the system is
operating.
The system can be activated or
deactivated in the Info-Display,
vehicle personalisation 3 122.
Deactivation is indicated by a message in the Driver Information
Centre.
Detection zones
The detection zones start at the rear
bumper and extend approx.
three metres rearwards and to the
sides. The height of the zone is
approx. between half a metre and
two metres off the ground.
Side blind spot alert is designed to
ignore stationary objects, e.g.
guardrails, posts, curbs, walls and
beams. Parked vehicles or oncoming
vehicles are not detected.
Fault
Occasional missed alerts can occur
under normal circumstances and will
increase in wet conditions.Side blind spot alert does not operate when the left or right corners of the
rear bumper are covered with mud,
dirt, snow, ice, slush, or in heavy
rainstorms. Cleaning instructions
3 257.
In the event of a fault in the system or if the system does not work due to
temporary conditions, the symbols in
the mirrors will be permanently
illuminated and a message is
displayed in the Driver Information
Centre. Seek the assistance of a
workshop.
Rear view camera
The rear view camera assists the
driver when reversing by displaying a view of the area behind the vehicle.
The view of the camera is displayed
in the Colour-Info-Display.9 Warning
The rear view camera does not
replace driver vision. Note that
objects that are outside the
camera's field of view and the
advanced parking assist sensors,
e.g. below the bumper or
underneath the vehicle, are not
displayed.
Do not reverse the vehicle by only looking at the Info-Display and
check the surrounding area
behind and around the vehicle
before reversing.
Activation
Rear view camera is automatically
activated when reverse gear is
engaged.
Functionality