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180Driving and operating
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 press the brake
pedal, if you need to brake more
quickly.
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,
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182Driving and operating
Forward collision alert based onradar systemThe system uses the radar sensor
behind the radiator grille to detect a
vehicle directly ahead, in your path,
within a distance of max. 150 metres.
Activation
Forward collision alert operates
automatically above walking speed,
provided that Auto Collision
Preparation setting is not deactivated
in the vehicle personalisation menu
3 118.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
Press button E, the current setting is
shown in the Driver Information
Centre. Press button E again to
change the alert sensitivity. The
setting is also displayed in the Driver Information Centre.Note that the alert timing sensitivity
setting is shared with the following
distance setting of the adaptive cruise
control 3 173. So changing the alert
timing sensitivity changes the
adaptive cruise control following
distance setting.
Alerting the driver
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184Driving and operating
Deactivation
The system can be deactivated.
Press button V repeatedly
until Forward Collision Alert Off
appears in the Driver Information
Centre.
General information for both
variants of forward collision alert9 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
The system is designed to warn only for vehicles, but may react also to
other metallic objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance may be limited:
■ on winding roads,
■ when weather limits visibility, e.g. fog, rain, or snow,
■ when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage.
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your path. It is active at speeds above 40 km/h.When a preceding vehicle is detected
ahead, the distance is indicated in
seconds, displayed on a page in the
Driver Information Centre 3 107.
On Baselevel display set Settings
X with the Menu button and
select Following distance indication
via the adjuster wheel on the turn signal lever 3 107.
On Midlevel or Uplevel display, select
Info menu and press o to
select Following distance indication
3 107.
The minimum indicated distance is
0.5 seconds.
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Vehicle care235
No.Circuit16Vacuum pump, mass air flow
meter, water in fuel sensor, DC
transformer17–18Adaptive forward lighting19Adaptive forward lighting20Fuel pump21Rear power windows22ABS23Variable effort steering24Front power windows25Power outlets26ABS27Electric parking brake28Heated rear window29Left power seat30Right power seatNo.Circuit31Air conditioning system32Body control module33Heated front seats34Sunroof35Infotainment system36–37Right high beam38Left high beam39–40–41Vacuum pump42Radiator fan43Vehicle battery, DC transformer (only on vehicles with stop-start
system)44Headlamp washer system45Radiator fanNo.Circuit46Terminal 87, main relay47Lambda probe48Fog lights49Right low beam50Left low beam51Horn52Ignition53Ignition, ventilated front seats54Ignition55Power windows, mirror folding56Windscreen washer57–58–59Diesel fuel heating, emission
control system60Mirror heating61Mirror heating