136Driving and operating9Warning
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 22.
For unlocking or locking the doors,
see fault in radio remote control unit
or electronic key system 3 23.Starting 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.
Driving and operating137Turn 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
3 138.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 138.
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 3 138.
● Automatic transmission: during an Autostop, the engine can be
started by releasing the brake
pedal 3 138.Hybrid vehicles
● Press Start/Stop button.
● Depress brake pedal.
● Press Start/Stop button.
● Keep the brake pedal depressed until the activation of the hybrid
system is confirmed by the
illumination of READY in the
instrument cluster and an
accoustic signal.
Emergency shut off during driving
If the engine needs to be switched off during driving in case of emergency,
press Start/Stop for 5 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.
138Driving and operatingStarting 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. 5 minutes.
The selector lever must be in position P .
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.
Activation
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.
The system is ready to operate when
the LED in the button Ò is not
illuminated. To activate the system
when the system is deactivated,
press Ó.
If the stop-start system is temporarily not available and the button Ò is
pressed, the LED in the button
flashes.Deactivation
Deactivate the stop-start system
manually by pressing Ò. The
deactivation is indicated when the
LED in the button illuminates.
Autostop
Vehicles with manual transmission
An Autostop can be activated at a
standstill.
Activate an Autostop as follows: ● Depress the clutch pedal.
● Set the selector lever to neutral.
● Release the clutch pedal.
Driving and operating139The engine will be switched off whilethe ignition stays on.Vehicles with automatic transmission
If 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.
● The engine exhaust temperature is not too high, e.g. after driving
with high engine load.
● The ambient temperature is not too low or too high.
● The climate control system allows an Autostop.
● The brake vacuum is sufficient.
● The self-cleaning function of the exhaust filter is not active.
● The vehicle was driven at least at
walking speed since the last
Autostop.
Otherwise an Autostop will be
inhibited.Notice
The Autostop may be inhibited for
several hours after a battery
replacement or reconnection.
Certain settings of the climate control
system may inhibit an Autostop.
Climate control 3 123.
Immediately after higher speed
driving an Autostop may be inhibited.
New vehicle running-in 3 134.
Vehicle battery discharge protection
To ensure reliable engine restarts,
several vehicle battery discharge
protection features are implemented
as part of the stop-start system.
Power saving measures
During an Autostop, several electrical
features such as auxiliary electric
heater or rear window heating are
disabled or switched to a power
saving mode. The fan speed of the
climate control system is reduced to
save power.
140Driving and operatingRestart of the engine by the driver
Vehicles with manual transmission
Depress the clutch pedal without
depressing the brake pedal to restart the engine.
Vehicles with automatic transmission The engine is restarted in the
following cases:
● brake pedal released while the selector lever in position D or M
● brake pedal released or selector lever in position N when selector
lever is moved to position D or
M
● selector lever moved to position R
Restart of the engine by the stop- start system
The selector lever must be in neutral to enable an automatic restart.
If one of the following conditions
occurs during an Autostop, the
engine will be restarted automatically
by the stop-start system:● stop-start system manually deactivated
● driver's seat belt unfastened and driver's door opened
● engine temperature too low
● charging level of vehicle battery below a defined level
● brake vacuum not sufficient
● vehicle driven at least at walking speed
● climate control system requests engine start
● air conditioning manually switched on
If an electrical accessory, e.g. a
portable CD player, is connected to
the power outlet, a brief power drop
during the restart might be noticeable.Parking9 Warning
● Do not park the vehicle on an
easily ignitable surface. The
high temperature of the
exhaust system could ignite the
surface.
● Apply the parking brake.
● If the vehicle is on a level surface or uphill slope, engage
first gear or set the selector
lever to position P. On an uphill
slope, turn the front wheels
away from the kerb.
If the vehicle is on a downhill
slope, engage reverse gear or
set the selector lever to position
P . Turn the front wheels
towards the kerb.
● Close the windows.
● Switch off the engine.
● Remove the ignition key from the ignition switch or switch off
ignition on vehicles with power
Driving and operating141button. Turn the steering wheeluntil the steering wheel lock is
felt to engage.
● For hybrid vehicles, make sure READY is not illuminated in the
instrument cluster.
● Lock the vehicle.
● Activate the anti-theft alarm system.
● The engine cooling fans may run
after the engine has been
switched off 3 213.
Caution
After running at high engine
speeds or with high engine loads,
operate the engine briefly at a low load or run in neutral for
approx. 30 seconds before
switching off, in order to protect
the turbocharger.
Notice
In the event of an accident with airbag deployment, the engine is
switched off automatically if the
vehicle comes to a standstill within a
certain time.
In countries with extreme low
temperatures it may be necessary to park the vehicle without applied
parking brake. Make sure to park the
vehicle on a level surface.Engine exhaust9 Danger
Engine exhaust gases contain
poisonous carbon monoxide,
which is colourless and odourless and could be fatal if inhaled.
If exhaust gases enter the interior
of the vehicle, open the windows.
Have the cause of the fault
rectified by a workshop.
Avoid driving with an open load
compartment, otherwise exhaust
gases could enter the vehicle.
Exhaust filter
Automatic cleaning process
The exhaust filter system filters soot particles out of the exhaust gases.
The start of saturation of the exhaust
filter is indicated by the temporary
illumination of % or C ,
accompanied by a message in the
Driver Information Centre.
142Driving and operatingAs soon as the traffic conditions
permit, regenerate the filter by driving at a vehicle speed of at least 40 mph
until the control indicator
extinguishes.
Notice
On a new vehicle, the first exhaust
filter regeneration operations may
be accompanied by a burning smell,
which is normal. Following
prolonged operation of the vehicle at
very low speed or at idle, water
vapour can be emitted at the
exhaust on acceleration. This does
not affect the behaviour of the
vehicle or the environment.
Cleaning process not possible
If % or C stays on, accompanied
by an audible signal and a message,
this indicates that the exhaust filter
additive level is too low.
The reservoir must be topped-up
without delay. Seek the assistance of
a workshop.Catalytic converter
The catalytic converter reduces the
amount of harmful substances in the
exhaust gases.Caution
Fuel grades other than those listed on pages 3 201, 3 260 could
damage the catalytic converter or
electronic components.
Unburnt petrol will overheat and
damage the catalytic converter.
Therefore avoid excessive use of the starter, running the fuel tank
dry and starting the engine by
pushing or towing.
In the event of misfiring, uneven
engine running, a reduction in engine performance or other unusual
problems, have the cause of the fault
rectified by a workshop as soon as
possible. In an emergency, driving
can be continued for a short period,
keeping vehicle speed and engine
speed low.
AdBlue
General information
The selective catalytic reduction
(BlueInjection) is a method to
substantially reduce the nitrogen
oxides in the exhaust emission. This
is achieved by injecting a Diesel
Exhaust Fluid (DEF) into the exhaust
system. The ammonia released by
the fluid reacts with nitrous gases
(NO x) from the exhaust and turns it
into nitrogen and water.
The designation of this fluid is
AdBlue ®
. It is a non-toxic, non-
flammable, colourless and odourless
fluid which consists of 32% urea and
68% water.9 Warning
Avoid contact of your eyes or skin
with AdBlue.
In case of eye or skin contact,
rinse off with water.
Driving and operating143Caution
Avoid contact of the paintwork withAdBlue.
In case of contact, rinse off with water.
AdBlue freezes at a temperature of
approx. -11 °C. As the vehicle is
equipped with an AdBlue preheater,
the emissions reduction at low
temperatures is ensured. The AdBlue
preheater works automatically.
Notice
Frozen and again liquefied AdBlue is usable without quality loss.
The typical AdBlue consumption is
approx. 0.85 l per 600 miles, but can
also be higher depending on driving
behaviour (e.g. high load or towing).
Level warnings
Depending on the calculated range of AdBlue, different messages are
displayed in the Driver Information
Centre. The messages and the
restrictions are a legal requirement.
1. The first possible warning is Top
up emissions additive: Starting
prevented in 1500 mi .
When switching on the ignition,
this warning will show up once
briefly with the calculated range.
Additionally, control indicator u
will illuminate and a chime will
sound. Driving is possible without
any restrictions.
When driving, the message is
displayed every 200 miles until
the additive tank has been
topped-up.
2. The next warning level is entered with a range below 350 miles. The
message with the current range
will always be displayed when
ignition is switched on.
Additionally, control indicator u
will flash and a chime will sound. Refill AdBlue before entering the
next warning level.
When driving, the message is
displayed every 30 seconds untilthe additive tank has been
topped-up.
3. The last warning level is entered when the AdBlue tank is empty.
Restart of the engine is not
possible. The following warning
message will be displayed:
Top up emissions additive:
Starting prevented
Additionally, control indicator u
will flash and a chime will sound.
Refill the tank to a level of at least 5 l of AdBlue, otherwise restarting
of the engine is not possible.
High emission warnings In the event of a fault with the
emissions control system, different
messages are displayed in the Driver
Information Centre. The messages
and the restrictions are a legal
requirement.
1. If a fault is detected for the first time, the warning Emissions fault
is displayed.
Additionally, control indicators u,
C and Z will illuminate and a