Driving and operating191
The selected following distance is
indicated by filled distance bars in the
adaptive cruise control page.
Note that the following distance
setting is shared with the sensitivity
setting of forward collision alert.
Example: If setting 3 (far) is selected,
then the driver is warned sooner
before a possible collision, also if
adaptive cruise control is inactive or
switched off.
9 Warning
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
Following distance must be
adjusted or the system switched
off when required by the prevailing
conditions.
Detecting the vehicle ahead
The green illuminated vehicle ahead
control indicator A is displayed in the
speedometer when the system
detects a vehicle in the driving path.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles
ahead.
Deactivation Adaptive cruise control is deactivatedby the driver when:
● y is pressed.
● The brake pedal is depressed.
● The clutch pedal is depressed for
more than four seconds.
● The gear selector lever of automatic transmission is moved
to N.
The system is also automatically
deactivated when:
● Vehicle speed slows down below
28 mph or accelerates above
120 mph.
● The Traction Control system (TC)
is operating for more than
20 seconds.
● The Electronic Stability Control (ESC) is operating.
192Driving and operating● There is no traffic and nothingdetected on the road sides forseveral minutes. In this case,
there are no radar echoes and
the sensor may report that it is
blocked.
● The collision imminent braking system is applying the brakes.
● The radar sensor is blocked by an ice or water film.
● A fault is detected in the radar, engine or brake system.
When adaptive cruise control is
deactivated automatically, the control indicator m illuminates white and a
warning symbol is displayed as a pop-
up in the Driver Information Centre.
The stored speed is maintained.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press C to switch off adaptive cruise
control. The control indicator m
extinguishes. 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 need 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.
● 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 limits ● The system's automatic brake force does not permit hard
braking and the braking level
may not be sufficient to avoid a
collision.
Driving and operating193● After a sudden lane change, thesystem 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 brake for stopped vehicles,
pedestrians or animals.
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
future bend change. The system may lose the current vehicle ahead or
consider a vehicle which is not in the
actual lane. This can happen when
entering or exiting a bend or if the
bend gets stronger or weaker. If it no
longer detects any vehicle ahead,
then control indicator A will
extinguish.
If the centrifugal force is too high in a bend, the system slows down the vehicle slightly. This braking level is
not designed to avoid spinning off the bend. The driver is responsible for
reducing the selected speed before
entering a bend and in general to
adapt the speed to the road type and
to existing speed limits.
Motorways
On motorways, adapt the set speed
to the situation and the weather.
Always consider that adaptive cruise
control has a limited visibility range, a
limited braking level and a certain
reaction time to verify if a vehicle is on
the driving path or not. Adaptive
cruise control may not be able to
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 depress the brake
pedal, if you need to brake more
quickly.
194Driving and operatingHill and trailer considerations
System performance on hills and
when towing a trailer depends on your
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,
consult a workshop to verify and
correct the adaptive cruise control
sensor position.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation, 3 132.
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.
Driving and operating195Vehicle messages 3 126.
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 3 132 or that it
is not deactivated by pressing V
(depending on the system, see
following).
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 3 188.
● Forward collision alert based on
front camera system
on vehicles with traditional cruise
control or none 3 185.
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 maximum distance of
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
3 132.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
196Driving and operating
Press E; the current setting is shown
in the Driver Information Centre.
Press E again to change the alert
sensitivity. The setting is also displayed in the top line of the Driver
Information Centre.Note that the alert timing sensitivity
setting is shared with the following
distance setting of the adaptive cruise control. So changing the alert timing
sensitivity changes the adaptive
cruise control following distance
setting.
Alerting the driver
A green illuminated vehicle ahead
control indicator A illuminates in the
instrument cluster when the system has detected a vehicle in the driving
path. When the distance to a
preceding moving vehicle gets too
small or when approaching another
vehicle too rapidly and a collision is
imminent, the collision alert symbol
pops-up in the Driver Information
Centre. Simultaneously a warning
chime sounds.
Depress the brake pedal, if it is
required by the situation.
Vehicle care257No.Circuit1Engine control module2Lambda sensor3Fuel injection/Ignition system4Fuel injection/Ignition system5–6Mirror heating/Anti-theft alarm
system7Fan control/Engine control
module/Transmission control
module8Lambda sensor/Engine cooling9Rear window sensor10Vehicle battery sensor11Trunk release12Adaptive forward lighting/Auto‐
matic light control13ABS14Rear window wiper15Engine control moduleNo.Circuit16Starter17Transmission control module18Heated rear window19Front power windows20Rear power windows21Rear electrical centre22Left high beam (Halogen)23Headlamp washer system24Right low beam (Xenon)25Left low beam (Xenon)26Front fog lights27Diesel fuel heating28Start stop system29Electric parking brake30ABS31Adaptive cruise control32Airbag
336IndexAAccessories and vehicle modifications .......................... 229
Active Emergency Braking .........199
Active head restraints ..................38
Adaptive cruise control .......119, 188
Adaptive forward lighting ..119,
146, 240
Adjustable air vents ...................163
Airbag and belt tensioners .........114
Airbag deactivation ..............54, 114
Airbag system .............................. 52
Air conditioning regular operation ................................ 164
Air conditioning system .............. 156
Air intake .................................... 163
Air vents...................................... 163
Antilock brake system ................ 177
Antilock brake system (ABS) .....116
Anti-theft alarm system ................28
Anti-theft locking system .............. 27
Appearance care ........................285
Armrest ........................................ 48
Armrest storage ........................... 63
Ashtrays ..................................... 107
Automatic anti-dazzle ..................32
Automatic light control ...............143
Automatic locking ........................24
Automatic transmission .............173Autostop..................................... 168
Auxiliary heater ........................... 162
B
Battery discharge protection ......154
Battery voltage ........................... 129 Belts.............................................. 49
Bicycle rack .................................. 65
Bonnet ....................................... 230
Brake and clutch fluid .................290
Brake and clutch system ...........115
Brake assist ............................... 180
Brake fluid .................................. 234
Brakes ............................... 177, 234
Breakdown.................................. 283
Bulb replacement ....................... 237
C Capacities .................................. 307
Cargo management system ........91
Car Pass ...................................... 21
Catalytic converter .....................172
Central locking system ................23
Centre console lighting ..............153
Centre console storage ...............64
Changing tyre and wheel size ...269
Charging system ........................ 115
Child locks ................................... 25
Child restraint installation locations ................................... 57
Child restraints.............................. 56