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154Driving and operatingpreheating. Control indicators
illuminate and most electrical
functions are operable.Engine start
Press Engine Start/Stop briefly while:
● manual transmission: operating clutch pedal,
● automatic transmission: operating brake pedal with
selector lever in P or N.
Starting the engine 3 155.Ignition off
Press Engine Start/Stop briefly when
Autostop is activated or when engine is running and vehicle is stationary.
Automatic transmission: apply the
parking brake and engage P.
Press Engine Start/Stop briefly
without operating clutch or brake pedal when in ignition on power
mode.
Some functions remain active until
driver's door is opened, provided the
ignition was on previously.Emergency engine shut off during
driving
Press Engine Start/Stop for more
than 2 seconds or press twice briefly
within 5 seconds 3 155.
Steering wheel lock The steering wheel lock activates
automatically when:
● The vehicle is stationary.
● The ignition has been switched off.
● The driver's door is opened.
To release steering wheel lock, open
and close driver's door and switch on accessory mode or start the engine
directly.9 Warning
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,
the Driver Information Centre may
display No Remote Detected or
Replace Battery in Remote Key when
you try to start the vehicle.
Open the cover of the centre console
in front of the selector lever. Place the
electronic key across with buttons
upside in the transmitter pocket
beside the power outlet, as shown in
the illustration.
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Driving and operating155Other objects, e.g. other keys,
transponder, tags, coins etc. must be
removed from the pocket.
Depress the clutch pedal (manual
transmission), the brake pedal and
press Engine Start/Stop . Release the
button after starting procedure
begins.
To switch off the engine, press
Engine Start/Stop again. Remove the
electronic key from the transmitter
pocket.
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 26.
Retained power off The following electronic systems can
work until the driver's door is opened
or for 10 minutes after the ignition is
switched off:● power windows
● sunroof
● power outlets
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: turn the key to
position 2 for preheating and wait until
control indicator ! extinguishes.
Turn key briefly to position 3 and
release: an automatic procedure operates the starter with a short delay
until the engine is running, see
Automatic Starter Control.
Manual transmission: during an
Autostop, the engine can be started
by depressing the clutch pedal
3 157.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 157.
Vehicles with power button
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168Driving and operating● Special programmesautomatically adapt the shiftingpoints when driving up inclines or
down hills.
● In snowy or icy conditions or on other slippery surfaces, the
electronic transmission control
enables the driver to manually
select first, second or third gear
for starting off.
Kickdown Pressing down the accelerator pedal
beyond the kickdown detent will lead to maximum acceleration
independent of the selected driving
mode. The transmission shifts to a
lower gear depending on engine
speed and shifts to a higher gear at
high engine revolutions.
Overheat protection
In the event of transmission-
overheating due to high outside
temperatures or sporty driving style,
the torque and the maximum speed of the engine can be temporarily
reduced.Fault
In the event of a fault a vehicle
message is displayed in the Driver
Information Centre.
Vehicle messages 3 122.
6-gear automatic transmission:
electronic transmission control
enables only fourth gear; 8-gear
automatic transmission: electronic
transmission control enables only
third gear. The transmission no
longer shifts automatically.
Have the cause of the fault remedied
by a workshop.
Interruption of power supply
In the event of an interruption of
power supply, the selector lever
cannot be moved out of the P
position.
The ignition key cannot be removed from the ignition switch.
If the vehicle battery is discharged,
start the vehicle using jump leads
3 269.
If the vehicle battery is not the cause
of the fault, release the selector lever.1. Apply parking brake.
2. Release the selector lever trim from the centre console. Poke
with a finger into the leather
socket beside the selector lever
and pull the trim up carefully, there
is a cable attached to it. Slide trim slightly forward as it is hinged on
its rear side. Tilt loose trim to the
left side to aviod tensioning the
cable.
Page 306 of 315

304Customer informationVehicle data recording
and privacy
Event data recorders
Electronic control units are installed in
your vehicle. Control units process
data which is received by vehicle
sensors, for example, or which they
generate themselves or exchange
amongst themselves. Some control
units are necessary for the safe
functioning of your vehicle, others
assist you while you drive (driver
assistance systems), while others
provide comfort or infotainment
functions.
The following contains general
information about data processing in
the vehicle. You will find additional
information as to which specific data
is uploaded, stored and passed on to third parties and for what purpose in
your vehicle under the key word Data Protection closely linked to the
references for the affected functional
characteristics in the relevant owner's manual or in the general terms of
sale. These are also available online.Operating data in the vehicle
Control units process data for
operation of the vehicle.
This data includes, e.g.: ● vehicle status information (e.g. speed, movement delay, lateral
acceleration, wheel rotation rate,
"seat belts fastened" display)
● ambient conditions (e.g. temperature, rain sensor,
distance sensor)
As a rule such data is transient, not
stored for longer than an operational
cycle, and only processed on board
the vehicle itself. Control units often
include data storage (including the vehicle key). This is used to allowinformation to be documented
temporarily or permanently on vehicle
condition, component stress,
maintenance requirements and
technical events and errors.Depending on technical equipment
level, the data stored is as follows:
● system component operating states (e.g. fill level, tyre
pressure, battery status)
● faults and defects in important system components (e.g. lights,
brakes)
● system reactions in special driving situations (e.g. triggering
of an airbag, actuation of the
stability control systems)
● information on events damaging the vehicle
● for electric vehicles the amount of
charge in the high-voltage
battery, estimated range
In special cases (e.g. if the vehicle
has detected a malfunction), it may be
necessary to save data that would
otherwise just be volatile.
When you use services (e.g. repairs,
maintenance), the operating data
saved can be read together with the
vehicle identification number and
used when necessary. Staff working
for the service network ( e.g. garages,
manufacturers) or third parties (e.g.