Page 195 of 317

Driving and operating1939Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control
immediately.
Switching off the system
Press C to switch off adaptive cruise
control. The control indicator C
extinguishes in the Driver Information Centre. The stored speed is deleted.
Switching off the ignition also
switches off adaptive cruise control
and deletes the stored speed.
Driver's attention ● Use adaptive cruise control carefully on bends or mountain
roads, as it can lose the vehicle
ahead and needs time to detect it again.
● Do not use the system on slippery roads as it can create
rapid changes in tyre traction
(wheel spinning), so that you
could lose control of the vehicle.
● Do not use adaptive cruise control during rain, snow or
heavy dirt, as the radar sensor
can be covered by a water film,
dust, ice or snow. This reduces or suppresses completely the
visibility. In case of sensor
blockage, clean the sensor
cover.
System limits9 Warning
The system's automatic brake
force does not permit hard braking and the braking level may not be
sufficient to avoid a collision.
● After a sudden lane change, the system needs a certain time to
detect the next preceding
vehicle. So if a new vehicle is
detected, the system may
accelerate instead of braking.
● Adaptive cruise control does ignore the oncoming traffic.
● Adaptive cruise control does not consider pedestrians and
animals for braking and driving
off.
● Adaptive cruise control considers
stopped vehicles only at low
speed.
● Do not use adaptive cruise control when towing a trailer.
● Do not use adaptive cruise control on roads with an incline ofmore than 10%.
Bends
The adaptive cruise control calculates
a predicted path based on the
centrifugal force. This predicted path
considers the current bend
characteristic, but cannot consider a
Page 197 of 317

Driving and operating195System 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. Full speed range
adaptive control is deactivated
automatically, as the vehicle is
stopping uphill on an incline greater
than 10%. In this condition, be
prepared to take control of the
vehicle.
Note that applying the brake
deactivates the system.
Radar unitThe radar unit is mounted behind the
radiator grille behind or below the
brand emblem.9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, in the event of a front-
end impact, 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 adjust the radar unit
position.
Settings
Settings can be changed in the
vehicle personalisation menu in the
Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Info-Display.
Info-Display 3 120.
Vehicle personalisation 3 124.
Fault
If the adaptive cruise control does not
work due to temporary conditions
(e.g. blockage by ice, overheated
brakes or low speed manoeuvres) or
if there is a permanent system error,
then a message is displayed in the
Driver Information Centre.
Vehicle messages 3 123.
Forward collision alert The forward collision alert may help toavoid or reduce the harm caused by
front-end crashes.
If the vehicle is equipped with
conventional cruise control, the
forward collision alert uses the front
camera in the windscreen to detect a
vehicle directly ahead, in your path.
If the vehicle is equipped with
adaptive cruise control, the forward
collision alert uses the radar sensor to
detect a vehicle directly ahead, in
your path.
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198Driving and operatingOn forward collision alert with front
camera press V repeatedly until
Forward Collision Alert Off appears in
the Driver Information Centre.
If the forward collision alert was
deactivated, alert sensitivity is set to
"medium" when ignition is switched on next time.
The last selected setting will be stored
when the ignition is switched off.
General information9 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
Forward collision alert is designed to warn on vehicles only, but may reactalso to other objects.
In 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 and the Radar sensor
are 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, 3 115
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Driving and operating201After 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.
Intelligent Brake Assist
If the vehicle is equipped with radar
sensor Intelligent brake assist may
activate when the brake pedal is
applied quickly by providing a boost
to braking based on the speed of
approach and distance to a vehicle
ahead.
Minor brake pedal pulsations or pedal movement during this time is normal
and the brake pedal should continue to be applied as needed. Intelligent
brake assist will automatically
disengage only when the brake pedal is released.
9 Warning
Intelligent brake assist may
increase vehicle braking in
situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
Deactivation
On vehicles with front camera active
emergency braking can be
deactivated by repeatedly pressing
the gap switch V to Off setting,
3 195. If deactivated a message is
displayed in the Driver Information
Centre.
On vehicles with radar sensor the
system can be disabled in the
personalisation menu in the Info-
display, 3 124.
System limitations In 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.
Page 225 of 317

Driving and operating223
The fuel filler flap can only be opened
if the vehicle is unlocked. Release the
fuel filler flap by pushing the flap.
Petrol and Diesel refuelling To open, turn the cap slowly
anticlockwise.The fuel filler cap can be retained in
the bracket on the fuel filler flap.
To refuel, switch on pump nozzle.
After the automatic cut-off, the tank can be topped up by operating the
pump nozzle a maximum of two more
times.
Caution
Wipe off any overflowing fuel
immediately.
To close, turn the fuel filler cap
clockwise until it clicks.
Close the flap and engage.
Misfuel inhibitor9 Warning
Do not try to open the flap of the
fuel filler neck manually on
vehicles with misfuel inhibitor.
Disregarding this could lead to
trapping of the fingers.
The misfuel inhibitor ensures that the flap of the fuel filler neck can only be
opened by using the suitable fuel
nozzle or a funnel for emergency
refilling.
In case of an emergency, refill with a
canister. A funnel must be used to
open the cap of the filler neck.
The funnel may be stowed in the load
compartment or the glovebox.
Place the funnel in straight position to the filler neck and press with slight
force to insert.
After topping-up, clean funnel from
fuel remains and stow it away.
Page 226 of 317

224Driving and operatingNatural gas refuelling
The fuel filler flap can only be opened
if the vehicle is unlocked. Release the
fuel filler flap by pushing the flap.
9 Warning
Refuel only with a maximum
output pressure of 250 bar. Use
only temperature-compensated
filling stations.
The refuelling procedure must be
completed, i.e. the filler neck must be
vented.
The capacity of the natural gas tank depends on outside temperature,
filling pressure, gas composition and
type of refuelling system. Capacities
3 295.
Close the flap and allow it to engage. Terms for "natural gas vehicles"
abroad:GermanErdgasfahrzeugeEnglishNGVs = Natural Gas Vehi‐
clesFrenchVéhicules au gaz naturel -
or - Véhicules GNVItalianMetano auto
Terms for "natural gas" abroad:
GermanErdgasEnglishCNG = Compressed
Natural GasFrenchGNV = Gaz Naturel (pour)
Véhicules - or -
CGN = carburantgaz
naturelItalianMetano (per auto)Fuel filler cap
Only use genuine fuel filler caps. Diesel-engined vehicles have special fuel filler caps.
Page 229 of 317
Driving and operating227
Disengage and fold down the
connecting socket. Remove the
sealing plug from the opening for the
coupling ball bar and stow it.
Checking the tensioning of the
coupling ball bar
● Red marking on rotary knob must
point towards green marking on
coupling ball bar.
● The gap between the rotary knob
and the coupling ball bar must be approx. 6 mm.
● The key must be in position c.
Otherwise, the coupling ball bar must be tensioned before being inserted:
● Unlock coupling ball bar by turning key to position c.
● Pull out rotary knob and turn
clockwise as far as it will go.
Inserting the coupling ball bar
Page 230 of 317

228Driving and operatingInsert the tensioned coupling ball bar
in the opening and push firmly
upwards until it audibly engages.
The rotary handle snaps back into its
original position resting against the
coupling ball bar without a gap.9 Warning
Do not touch rotary handle during
insertion.
Lock the coupling ball bar by turning
the key to position e. Remove the key
and close the protective flap.
Eye for break-away stopping cable
Illustration shows 5-door hatchback.
Illustration shows Sports Tourer.
Attach breakaway stopping cable to eye.
Check that the coupling ball bar is
correctly installed
● Green marking on rotary knob must point towards green
marking on coupling ball bar.
● There must be no gap between the rotary handle and the
coupling ball bar.
● The coupling ball bar must be firmly engaged in the opening.
● The coupling ball bar must be locked and the key removed.9Warning
Towing a trailer is permitted only
when a coupling ball bar is fitted correctly. If the coupling ball bardoes not engage correctly, seekthe assistance of a workshop.
Dismounting the coupling ball bar