Driving and operating157Driving and
operatingDriving hints ............................... 158
Control of the vehicle ...............158
Steering ................................... 158
Starting and operating ...............158
New vehicle running-in ............158
Ignition switch positions ...........158
Power button ........................... 159
Retained power off ..................160
Starting the engine ..................161
Overrun cut-off ........................ 163
Stop-start system ....................163
Parking .................................... 166
Engine exhaust .......................... 168
Diesel particle filter ..................168
Catalytic converter ...................169
Automatic transmission ..............169
Transmission display ...............169
Selector lever .......................... 170
Manual mode ........................... 171
Electronic driving programmes 171
Fault ........................................ 171
Interruption of power supply ....172
Manual transmission ..................173Manual transmission automa‐
ted .............................................. 173
Transmission display ...............174
Selector lever .......................... 174
Manual mode ........................... 175
Electronic driving programmes 176
Fault ........................................ 176
Brakes ........................................ 176
Antilock brake system .............176
Parking brake .......................... 177
Brake assist ............................. 179
Hill start assist ......................... 179
Ride control systems .................179
Traction Control system ..........179
Electronic Stability Control ......180
Sport mode .............................. 182
Driver assistance systems .........182
Cruise control .......................... 182
Speed limiter ........................... 184
Adaptive cruise control ............186
Forward collision alert .............193
Following distance indication ...196
Active emergency braking .......197
Parking assist .......................... 200
Side blind spot alert .................207
Rear view camera ...................209
Traffic sign assistant ................211
Lane keep assist .....................215Fuel............................................ 217
Fuel for petrol engines .............217
Fuel for diesel engines ............218
Fuel for natural gas operation . 219
Refuelling ................................ 219
Fuel consumption - CO 2-
Emissions ............................... 221
Trailer hitch ................................ 222
General information .................222
Driving characteristics and towing tips .............................. 222
Trailer towing ........................... 223
Towing equipment ...................223
Trailer stability assist ...............226
Driving and operating197Active emergency braking
Active emergency braking can help to reduce the damage and injury 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 3 193.
The feature uses various inputs (e.g.
camera sensor, radar sensor, brake
pressure, vehicle speed) to calculate
the probability of a frontal collision.9 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 to reduce
the vehicle speed before a
collision.
The system may not react for
pedestrians or animals. After a
sudden lane change, the system
needs a certain time to detect the
next preceding vehicle.
The driver shall always be ready to take action and apply the brakes
and steer to avoid collisions.
Functionality
If equipped only with front camera the active emergency braking operates in
forward gear above walking speed up to 85 km/h.
With radar sensor active emergency
braking operates in forward gear
above walking speed at all speeds.
A precondition is that forward collision
alert with front camera system is not
deactivated by pressing V on the
steering wheel 3 193or, with radar
sensor, that it is not deactivated in the
vehicle personalisation menu 3 125.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist
● intelligent brake assist (only with radar sensor)
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightlypressurizes 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.
If equipped only with front camera the system operates up to a speed of 80
km/h.
Emergency automatic braking After activation of brake preparation
system and just before the imminent
collision, this function automatically
applies limited braking to reduce the
impact speed of the collision or
prohibit a crash. Depending on the
situation, the vehicle may
automatically brake moderately or
hard. This front automatic braking can
198Driving and operatingonly occur if a vehicle ahead is
detected, indicated by the vehicle ahead indicator A 3 193.
If equipped only with front camera the
system operates up to a speed of 60
km/h.
Below a speed of 40 km/h the system can apply full braking.
Emergency automatic braking may
slow the vehicle to a complete stop to
try to avoid a potential crash. If this
happens, emergency automatic
braking may engage the electric
parking brake to hold the vehicle at a
stop. To release press the electric
parking brake button or firmly press
the accelerator pedal.9 Warning
Emergency automatic braking is
an emergency crash preparation
feature and is not designed to
avoid crashes. Do not rely on the
system to brake the vehicle.
Emergency automatic braking will
not brake outside of its operating speed range and only responds to
detected vehicles.
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, pressing
the brake pedal less strongly results
in immediate hard braking. This
function helps the driver brake
quicker and harder before the
imminent collision.
If equipped only with front camera the
system operates up to a speed of 85
km/h.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 pedestrians 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 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.
Driving and operating1999Warning
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,
3 193. 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, 3 125.
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.Emergency automatic braking may
not:
● detect a vehicle ahead on winding or hilly roads.
● detect all vehicles, especially vehicles with a trailer, tractors,
muddy vehicles, etc.
● detect a vehicle when weather limits visibility, such as in fog,rain, or snow.
To avoid malfunction keep the areas
of the camera sensor in the
windscreen and the radar sensor in
the radiator grille always clean from
dirt, dust, ice and snow.
Complete attention is always required
while driving, and you should be
ready to take action and apply the
brakes and/or steer the vehicle to
avoid crashes.
Fault
In case the system requires a service,
a message is displayed in the Driver
Information Centre.
210Driving and operating
The area displayed by the camera is
limited. The distance of the image that
appears on the display differs from
the actual distance.
Guiding lines
Dynamic guiding lines are horizontal
lines at one metre intervals projected
onto the picture to define the distance
to displayed objects.Trajectory lane of the vehicle is
shown in accordance with the
steering angle.
Warning symbols
Warning symbols are indicated as
triangles 9 on the picture, which show
obstacles detected by the rear
sensors of the advanced parking
assist.
Additionally, 9 appears on the top
line of the Info-Display with the
warning to check the vehicle
surrounding.
Deactivation
The camera is switched off when a
certain forward speed is exceeded or if reverse gear is not engaged for
approx. 15 seconds.
Deactivation of guiding lines and
warning symbols
7'' Colour-Info-Display: Activation or
deactivation of the visual guiding lines and the warning symbols can be
changed via touch buttons in the
lower zone of the display.
8'' Colour-Info-Display: Activation or
deactivation of the visual guiding lines
and the warning symbols can be
Driving and operating215Fault
Traffic sign assistant may not operate correctly if:
● The area of the windscreen, where the front camera is
located, is not clean or affected
by foreign items, e.g. stickers.
● Traffic signs are completely or partially covered or difficult to
discern.
● There are adverse environmental
conditions, e.g. heavy rain, snow,
direct sunlight or shadows.
● Traffic signs are incorrectly mounted or damaged.
● Traffic signs do not comply with the Vienna Convention on traffic
signs (Wiener Übereinkommen
über Straßenverkehrszeichen).Caution
The system is intended to help the driver within a defined speed
range to discern certain traffic
signs. Do not ignore traffic signs
which are not displayed by the
system.
The system does not discern any other than the conventional traffic
signs that might give or end a
speed limit.
Do not let this special feature
tempt you into taking risks when
driving.
Always adapt speed to the road
conditions.
The driver assistance systems do not relieve the driver from full
responsibility for vehicle
operation.
Lane keep assist
Lane keep assist helps to avoid
crashes due to unintentional lane
departures. The front camera
observes the lane markings between
which the vehicle is driving. If the
vehicle approaches a lane marking, the steering wheel is gently turned to
position the vehicle back into the lane. Turn steering wheel in same
direction, if system steers not
sufficient. Turn steering wheel gently
into opposite direction, if lane change is intended.
When crossing a lane marking
significantly, lane keep assist starts a
visual and acoustic warning.
Unintended lane departure is
assumed
● without using turn signal● using the turn signal in the opposite direction of the lane
departure
● without braking
● without acceleration
● without active steering.
Note
The system is switched off during
detection of ambiguous lane
markings, e.g. in construction areas.
Note
The system may be switched off if it
detects lanes which are too narrow,
too wide or too curved.
216Driving and operatingActivation
The lane keep assist is activated by
pressing a. The LED in the button
illuminates to indicate that the system
is switched on.
When the control indicator a in the
instrument cluster illuminates green,
the system is ready to assist.
The system is operational at vehicle
speeds between 60 km/h and
180 km/h and if lane markings are
available.
The system gently turns the steering
wheel and the control indicator a
changes to yellow, if the vehicle
approaches a detected lane marking
without using the turn signal in that
direction.
The system alerts by flashing a
together with three chimes, from the
respective direction, if the lane is
departed significantly.
The system is only operable when a
lane marking is detected.
If the system only detects lane
markings on one side of the road, it
will only assist for this side.
Lane keep assist detects hands-free
driving. In this case a message in the
Driver Information Centre pops-up
and a chime sounds as long as lane
keep assist detects hands-free
driving.Deactivation
The system is deactivated by
pressing a; the LED in the button
extinguishes.
Fault
The system performance may be
affected by:
● Windscreen not clean or affected
by foreign items, e.g. stickers
● Close vehicles ahead
● Banked roads
● Winding or hilly roads
● Road edges
● Roads with poor lane markings
● Sudden lighting changes
● Adverse environmental conditions e.g. heavy rain or
snow
● Vehicle modifications, e.g. tyres.
Switch off the system if the system is
disturbed by tar marks, shadows, road cracks, temporary or
construction lane markings, or other
road imperfections.
Driving and operating2179Warning
Always keep your attention on the
road and maintain proper vehicle
position within the lane, otherwise
vehicle damage, injury or death
could occur.
Lane keep assist does not
continuously steer the vehicle.
The system may not keep the
vehicle in the lane or give an alert,
even if a lane marking is detected.
The steering of the lane keep
assist may not be sufficient to
avoid a lane departure.
The system may not detect hands-
off driving due to external
influences (road condition and
surface, weather etc). The driver
has full responsibility to control the vehicle and is always required tokeep the hands on the steeringwheel while driving.
Using the system while towing a
trailer or on slippery roads could
cause loss of control of the vehicle
and a crash. Switch the system off.
Fuel
Fuel for petrol engines Only use unleaded fuel that complies
with European standard EN 228 or equivalent.
The engine is capable of running with fuel that contains up to 10% ethanol
(e.g. named E10).
Use fuel with the recommended
octane rating. A lower octane rating
can reduce engine power and torque
and slightly increases fuel
consumption.Caution
Do not use fuel or fuel additives
that contain metallic compounds
such as manganese-based
additives. This may cause engine
damage.
Caution
Use of fuel that does not comply to EN 228 or equivalent can lead todeposits or engine damage.
Caution
Use of fuel with a lower octane
rating than the lowest possible
rating could lead to uncontrolled combustion and engine damage.
The engine-specific requirements
regarding octane rating are given in
the engine data overview 3 285. A
country-specific label at the fuel filler
flap can supersede the requirement.
Fuel additives outside Europe
Fuel should contain detergent
additives that help prevent engine
and fuel system deposits from
forming. Clean fuel injectors and
intake valves will allow the emission
control system to work properly.