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Driving and operating191
On Baselevel display set Settings
X with the Menu button and select
Following distance indication via the
adjuster wheel on the turn signal lever
3 111.
On Midlevel or Uplevel display, select
Info menu and press o to select
Following distance indication 3 111.
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: -.- s.
If Adaptive cruise control is active,
this page shows the following
distance setting instead 3 180.
Active Emergency Braking
Active emergency braking can help to reduce the damage 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 3 187.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability ofa frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto Collision
Preparation setting is not deactivated
in the vehicle personalisation menu
3 122.The system includes:
■ brake preparation system
■ emergency automatic braking
■ forward looking brake assist9 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. 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.
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192Driving and operating
Emergency automatic brakingAfter the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of the collision.
Below a speed of 11 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.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 stopped vehicles,
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 radar
sensor can be covered by a water
film, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
In some cases, the active emergency braking 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.
Settings Settings can be changed in the
vehicle personalisation menu in the
Colour-Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Colour-Info-Display.
Colour-Info-Display 3 118.
Vehicle personalisation 3 122.
Fault In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
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Driving and operating193
If the system does not work as it
should do, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 120.
Parking assist9 Warning
The driver bears full responsibility
for the parking manoeuvre.
Always check the surrounding
area when driving backwards or
forwards while using parking
assist system.
Front-rear parking assist
The front-rear parking assist
measures the distance between the vehicle and obstacles in front and
behind the vehicle. The system gives acoustic signals and display
messages.
The system has four ultrasonic
parking sensors each in the rear and front bumper.
It uses two different acoustic warning
signals for the front and rear
monitoring areas, each with a
different tone frequency. The signal
for front obstacles sounds via the
front speakers, for rear obstacles it
sounds from the rear of the vehicle.
Activation
When reverse gear is engaged, the
front and rear parking assist is ready
to operate.
The front parking assist is also
activated automatically at a speed up
to 7 mph.
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194Driving and operating
An illuminated LED in the parking
assist button r indicates that the
system is ready to operate.
If the vehicle exceeds a speed of
7 mph, the front parking assist is
deactivated. The front parking assist
is always reactivated when vehicle
speed drops below 7 mph.
Indication
The system warns the driver with
acoustic signals against potentially
hazardous obstacles behind and in
front of the vehicle. Depending on
which side of the vehicle is closer to
an obstacle, you will hear acoustic
warning signals on the respective
side of the vehicle. 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 obstacles is shown in the Driver Information
Centre 3 111.
The distance to a front and rear
obstacle is indicated by changing
distance lines around the vehicle.
Rear obstacles are indicated
acoustically and visually at the same
time.
Front obstacles are indicated visually
first. At distances less than 80 cm an
acoustic signal also sounds.
The distance indication in the Driver
Information Centre can be inhibited
by vehicle messages with a higher
priority. After approving the message
by pressing the SET/CLR button on
the turn signal lever or 9 on right
steering wheel control, distance
indication appears again.
Deactivation
The rear parking assist automatically
switches off when reverse gear is
disengaged.
The front parking assist is deactivated
automatically at a speed above
7 mph.
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Driving and operating195
Manual deactivation is possible by
pressing the parking assist button
r briefly.
When the system is deactivated, the
LED in the button extinguishes.
Additionally, Park Assist Off pops-up
in the Driver Information Centre when the system is deactivated manually.
After a manual deactivation, the front
parking assist is activated again if the
parking assist button r is pressed
or if reverse gear is engaged.
Fault
In the event of a fault in the system or if the system does not work due to
temporary conditions, e.g. ice
covered sensors, a message is
displayed in the Driver Information
Centre.
Vehicle messages 3 120.
Advanced parking assist9 Warning
The driver bears full responsibility
for accepting the parking slot
suggested by the system and the
parking manoeuvre.
Always check the surrounding
area in all directions when using
advanced parking assist.The advanced parking assist system manoeuvres the driver into a parkingslot by giving instructions on the
Driver Information Centre and
acoustic signals. The driver must
control acceleration, braking, steering
and gear shifting.
The system uses the sensors of the
parking assist system in combination
with two additional sensors on both
sides of the front and rear bumper.
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196Driving and operating
Activation
When searching for a parking slot, the
system is ready to operate by
pressing button (.
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.
Functionality
When the vehicle passes a row of
cars and the system is activated, the
advanced parking assist system
begins looking for a suitable parking
slot. When a suitable slot is detected, a visual feedback and acoustic
signals are given in the Driver
Information Centre.
If the driver does not stop the vehicle
within 10 metres after a parking slot is
proposed, the system starts to search
for another suitable parking slot.
The parking slot suggestion of the
system is accepted when the vehicle
is stopped by the driver within
10 metres after the "Stop" message is
given. The system calculates the
optimal route into the parking slot.
Then it manoeuvres the driver into the
slot by giving detailed instructions.
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Driving and operating197
The instructions in the display show:■ A hint when driving faster than 18 mph.
■ The demand to stop the vehicle, when a parking slot is detected.
■ The direction of driving during the parking manoeuvre.
■ The steering wheel position during parking.
■ For some of the instructions a progress bar is shown.A successful parking manoeuvre is
indicated by the End position
message.
Always pay attention to the sound of
the front-rear parking assist.
Continuous sound means that the
distance to an obstacle is less than
approx. 30 cm.
Changing the parking side
The system is configured to detect parking slots on the passenger side.
To detect parking slots on the driver
side, press ( for approx. 2 seconds.
Display priorities
After activating the advanced parking assist, a message appears in the
Driver Information Centre. Advanced
parking assist indication in the Driver
Information Centre can be inhibited
by vehicle messages with a higher
priority. After approving the message
by pressing the SET/CLR button on
the turn signal lever or the 9 button
in the steering wheel controls,
advanced parking assist instructions
appear again and the parking
manoeuvre can be continued.
Deactivation
The system is deactivated by:
■ pressing (
■ parking manoeuvre successfully ended
■ driving faster than 18 mph
■ switching off the ignition
Notice
If advanced parking assist is
deactivated manually or by the
system (e.g. parking manoeuvre
ended), the front and rear parking
assist is also deactivated.
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198Driving and operating
Reactivate front and rear parking
assist by pressing parking assist
button r or engaging reverse gear
once.
Deactivation by the driver or by the
system during manoeuvring will be
indicated by Parking Deactivated in
the Driver Information Centre.
Fault
A message appears in the Driver
Information Centre when:
■ There is a fault in the system.
■ The driver did not successfully complete the parking manoeuvre.
■ The system is not operational.
If an object is detected during parking instructions, Stop is indicated in the
Driver Information Centre. Removing
the object will resume the parking
manoeuvre. If the object is not
removed, the system will be
deactivated. Press ( to activate the
system and search for a new parking
slot.
Basic notes on using 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