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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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Driving and operating185
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 3 173.
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 3 181.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability of
a frontal collision.
Active emergency braking operates automatically above walking speed, provided that Auto Collision
Preparation setting is not deactivated
in the vehicle personalisation menu
3 118.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.
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.
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 slightly
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,
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186Driving and operatingpedestrians 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 wearing their 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 a short
automatic braking in situations that
seem to be unnecessary, for instance
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 3 114.
Vehicle personalisation 3 118.
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 3 116.
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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