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182Driving and operating
Hill and trailer considerations
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. It is not
recommended to use adaptive cruise
control on steep hills.
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,
consult a workshop to verify and
correct the adaptive cruise control
sensor position.
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 3 117.
Vehicle personalisation 3 121.
Fault
If the adaptive cruise control does not
work due to temporary conditions
(e.g. blockage by ice) or if there is a
permanent system error, then a
message is displayed in the Driver
Information Centre.
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Driving and operating183
Vehicle messages 3 119.
Forward collision alert The forward collision alert can help to
avoid or reduce the harm caused by
front-end crashes.
A vehicle ahead is indicated by a
control indicator A.
If a vehicle directly ahead is
approached too quickly, a warning
chime and alert in the Driver
Information Centre is provided.
A precondition is that forward collision
alert is activated in the vehicle
personalisation menu 3 121 or that it
is not deactivated by the button V
(depending on the system, see
below).
Depending on the vehicle's
equipment, there are two variants of
the forward collision alert available:
■ Forward collision alert based on
radar system
on vehicles equipped with adaptive cruise control 3 175.
■ Forward collision alert based on
front camera system
on vehicles with no cruise control or traditional cruise control only
3 173.
Forward collision alert based on radar system
The 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
3 121.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
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186Driving and operating
General information for bothvariants 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 lane.
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 3 110.On Baselevel display set Settings
X with the Menu button and select
Following distance indication via the
adjuster wheel on the turn signal lever 3 110.
On Midlevel or Uplevel display, select
Info menu and press o to select
Following distance indication 3 110.
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.
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Vehicle care237
No.Circuit1Transmission control module2Engine control module3–4–5Ignition, Transmission control
module, Engine control module6Windscreen wiper7–8Fuel injection, ignition system9Fuel injection, ignition system10Engine control module11Lambda probe12Starter13Sensor throttle heating14Lighting15Rear window wiperNo.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 fan