Page 145 of 283
Climate control143Maintenance
Air intake
The air intake in front of the
windscreen in the engine
compartment must be kept clear to
allow air intake. Remove any leaves,
dirt or snow.
Air conditioning regular
operation
In order to ensure continuously
efficient performance, cooling must
be operated for a few minutes once a
month, irrespective of the weather
and time of year. Operation with
cooling is not possible when the
outside temperature is too low.
Service For optimal cooling performance, it is recommended to annually check the
climate control system, starting
three years after initial vehicle
registration, including:
● functionality and pressure test
● heating functionality
● leakage check
● check of drive belts
● cleaning of condenser and evaporator drainage
● performance check
Page 146 of 283

144Driving and operatingDriving and
operatingDriving hints ............................... 145
Control of the vehicle ...............145
Steering ................................... 145
Starting and operating ...............145
New vehicle running-in ............145
Ignition switch positions ...........145
Power button ........................... 146
Power saving mode .................147
Starting the engine ..................148
Overrun cut-off ........................ 149
Stop-start system ....................149
Parking .................................... 152
Engine exhaust .......................... 153
Exhaust filter ............................ 153
Catalytic converter ...................154
AdBlue ..................................... 154
Automatic transmission ..............157
Transmission display ...............157
Selector lever .......................... 158
Manual mode ........................... 158
Electronic driving programmes 159
Fault ........................................ 160
Eco mode ................................ 160Manual transmission ..................160
Brakes ........................................ 161
Antilock brake system .............161
Parking brake .......................... 162
Brake assist ............................. 165
Hill start assist ......................... 165
Ride control systems .................165
Electronic Stability Control and Traction Control system .........165
Descent control system ...........166
Selective ride control ...............168
Driver assistance systems .........170
Cruise control .......................... 170
Speed limiter ........................... 172
Adaptive cruise control ............174
Forward collision alert .............181
Active emergency braking .......182
Front pedestrian protection .....185
Parking assist .......................... 186
Advanced parking assist .........190
Side blind spot alert .................194
Passenger side camera ...........195
Panoramic view system ...........196
Rear view camera ...................199
Lane keep assist .....................201
Driver alert ............................... 203
Fuel ............................................ 205
Fuel for petrol engines .............205Fuel for diesel engines ............205
Refuelling ................................ 206
Trailer hitch ................................ 208
General information .................208
Driving characteristics and towing tips .............................. 208
Trailer towing ........................... 208
Towing equipment ...................209
Trailer stability assist ...............211
Page 147 of 283

Driving and operating145Driving hints
Control of the vehicle
Never coast with engine not
running
Many systems will not function in this
situation ( e.g. brake servo unit, power
steering). Driving in this manner is a danger to yourself and others.
All systems function during an
Autostop.
Stop-start system 3 149.
Idle boost
If charging of the vehicle battery is
required due to battery condition, the
power output of the generator must be increased. This will be achieved by an idle boost which may be audible.
A message appears in the Driver
Information Centre.
Pedals
To ensure the pedal travel is
uninhibited, there must be no mats in
the area of the pedals.Use only floor mats, which fit properly and are fixed by the retainers on the
driver side.
Steering If power steering assist is lost
because the engine stops or due to a system malfunction, the vehicle can
be steered but may require increased
effort.Starting and operating
New vehicle running-in Do not brake unnecessarily hard for
the first few journeys.
During the first drive, smoke may
occur because of wax and oil
evaporating off the exhaust system. Park the vehicle in the open for a
while after the first drive and avoid
inhaling the fumes.
During the running-in period, fuel and engine oil consumption may be
higher.
Additionally, the cleaning process of
the exhaust filter may take place more
often.
Exhaust filter 3 153.
Autostop may be inhibited to allow
charging of the vehicle battery.
Ignition switch positions Turn key:
Page 148 of 283

146Driving and operating0:ignition off: some functions
remain active until key is
removed or driver's door is
opened, provided the ignition was
on previously1:ignition on power mode: ignition
is on, diesel engine is preheating, control indicators illuminate and
most electrical functions are
operable2:engine start: release key after
engine has been started
Steering wheel lock
Remove key from ignition switch and
turn steering wheel until it engages.
9 Danger
Never remove the key from
ignition switch during driving as
this will cause steering wheel lock.
Power button
The electronic key must be inside the
vehicle.
Engine start
Operate the clutch pedal (manual
transmission), the brake pedal and
press Start/Stop .Ignition on power mode without
starting the engine
Press Start/Stop without operating
clutch or brake pedal. Control
indicators illuminate and most
electrical functions are operable.Engine and ignition off
Press Start/Stop briefly in each mode
or when engine is running and vehicle
is stationary. Some functions remain
active until driver's door is opened,
provided the ignition was on
previously.Emergency shut off during driving
Press Start/Stop for about three
seconds 3 148. Steering wheel locks
as soon as vehicle is stationary.
Steering wheel lock
The steering wheel lock activates
automatically when:
● The vehicle is stationary.
● The ignition has been switched off.
To release steering wheel lock, open
and close driver's door and switch the ignition on power mode or start the
engine directly.
Page 149 of 283

Driving and operating1479Warning
If the vehicle battery is discharged,
the vehicle must not be towed,
tow-started or jump-started as the
steering wheel lock cannot be
disengaged.
Operation on vehicles with
electronic key system in case of
failure
If either the electronic key fails or the
battery of the electronic key is weak,
a message may be displayed in the
Driver Information Centre.
Hold the electronic key with buttons
outside at the marking on the steering column cover as shown in the
illustration.
Operate the clutch pedal (manual
transmission), the brake pedal and
press Start/Stop .
This option is intended for
emergencies only. Replace the
electronic key battery as soon as
possible 3 23.
For unlocking or locking the doors,
see fault in radio remote control unit
or electronic key system 3 25.
Power saving mode
This mode deactivates electrical
consumers to avoid excessive
discharging of the vehicle battery.
These consumers, such as the
infotainment system, windscreen
wipers, low beam headlights,
courtesy light, etc. can be used for a
total maximum time of about
40 minutes after ignition is switched
off.Changing into power saving
mode
When power saving mode is
activated, a message appears in the
Driver Information Centre indicating
Power saving mode .
An active telephone call using the
hands-free option will be maintained
for around 10 minutes longer.
Deactivating power saving mode
Power saving mode is deactivated
automatically when the engine is
restarted. Run the engine for a
sufficient charge:
● for less than 10 minutes to use the consumers for approx.
5 minutes
● for more than 10 minutes to use the consumers for up to approx.
30 minutes
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148Driving and operatingStarting the engine
Vehicles with ignition switch
Turn key to position 1 to release the
steering wheel lock.
Manual transmission: operate clutch
and brake pedal.
Automatic transmission: operate
brake pedal and move selector lever
to P or N.
Do not operate accelerator pedal.
Diesel engines: wait until control
indicator ! extinguishes.
Turn key briefly to position 2 and
release after engine has been
started.
Manual transmission: during an
Autostop, the engine can be started
by depressing the clutch pedal
3 149.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 149.
Vehicles with power button● Manual transmission: operate clutch and brake pedal.
● Automatic transmission: operate brake pedal and move selector
lever to P or N.
● Do not operate accelerator pedal.
● Press Start/Stop button.
● Release button after starting procedure begins. Diesel engine
starts after control indicator ! for
preheating extinguishes.
● Before restarting or to switch off the engine when vehicle is
stationary, press Start/Stop once
more briefly.
To start the engine during an
Autostop:
● Manual transmission: during an Autostop, the engine can be
started by depressing the clutch
pedal 3 149.
● Automatic transmission: during an Autostop, the engine can be
started by releasing the brake
pedal 3 149.
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Driving and operating149Emergency shut off during drivingIf the engine needs to be switched offduring driving in case of emergency,
press Start/Stop for five seconds.9Danger
Switching off the engine during
driving may cause loss of power
support for brake and steering
systems. Assistance systems and
airbag systems are disabled.
Lighting and brake lights will
extinguish. Therefore power down the engine and ignition while
driving only when required in case of emergency.
Starting the vehicle at low
temperatures
Starting the engine without additional
heaters is possible down to -25 °С for diesel engines and -30 °C for petrol
engines. Required is an engine oil
with the correct viscosity, the correct fuel, performed services and a
sufficiently charged vehicle battery.
With temperatures below -30 °C the
automatic transmission requires a
warming phase of approx.
five minutes. The selector lever must
be in position P.
Heating functionalities Note
Individual heating functionalities,
such as heated seats or heated
steering wheel, may be temporarily
unavailable in the event of electrical
loading constraints. Functions will
be resumed after some minutes.Turbo engine warm-up
Upon start-up, engine available
torque may be limited for a short time, especially when the engine
temperature is cold. The limitation is
to allow the lubrication system to fully
protect the engine.
Overrun cut-off
The fuel supply is automatically cut off
during overrun, i.e. when the vehicle
is driven with a gear engaged but accelerator pedal is released.
Depending on driving conditions, the
overrun cut-off may be deactivated.
Stop-start system The stop-start system helps to save
fuel and to reduce the exhaust
emissions. When conditions allow, it
switches off the engine as soon as the
vehicle is at a low speed or at a
standstill, e.g. at a traffic light or in a traffic jam.
Page 152 of 283

150Driving and operatingActivation
The stop-start system is available as
soon as the engine is started, the
vehicle starts-off and the conditions
as stated below in this section are
fulfilled.
Deactivation
Deactivate the stop-start system
manually by pressing Ò. The
deactivation is indicated when the
LED in the button illuminates.
AutostopVehicles with manual transmission
An Autostop can be activated at a
standstill or at a speed below
20 km/h.
Activate an Autostop as follows: ● Depress the clutch pedal.
● Set the selector lever to neutral.
● Release the clutch pedal.
The engine will be switched off while the ignition stays on.Vehicles with automatic transmissionIf the vehicle is at a standstill with
depressed brake pedal, Autostop is
activated automatically.
The engine will be switched off while the ignition stays on.
The stop-start system will be disabled
on inclines of 12% or more.Indication
An Autostop is indicated by control
indicator D.
During an Autostop, the heating and
brake performance will be
maintained.
Conditions for an Autostop
The stop-start system checks if each
of the following conditions is fulfilled.
● The stop-start system is not manually deactivated.
● The driver's door is closed or the driver's seat belt is fastened.
● The vehicle battery is sufficiently charged and in good condition.
● The engine is warmed up.
● The engine coolant temperature is not too high.