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154Driving and operatingPower button
Electronic key must be inside the
vehicle.
Accessory power mode
Press Engine Start/Stop once without
operating clutch or brake pedal. The yellow LED in the button illuminates.
Steering wheel lock is released and
some electrical functions are
operable, ignition is off.Ignition on power mode
Press and hold Engine Start/Stop for
six seconds without operating clutch
or brake pedal. The green LED in the button illuminates, diesel engine ispreheating. 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 two seconds or press twice
briefly within five 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.
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Driving and operating155Operation 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 gear shift lever. Place
the electronic key across with buttons
upside in the transmitter pocket
beside the power outlet, as shown in
the illustration.
Other objects, e.g. other keys,
transponder, tags, coins etc. must be removed from the pocket.
Depress the clutch pedal (manual
transmission) or the brake pedal
(automatic transmission) and press
Engine Start/Stop .
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 21.
For unlocking or locking the doors,
see fault in radio remote control unit
or electronic key system 3 23.
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 outletsStarting the engine
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 Engine Start/Stop briefly: an
automatic procedure operates the
starter with a short delay until the engine is running.
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Driving and operating159● The driver's seat belt isunfastened and the driver's door
is opened.
● The engine temperature is too low.
● The charging level of the vehicle battery is below a defined level.
● The brake vacuum is not sufficient.
● The vehicle is driven at least at walking speed.
● The climate control system requests an engine start.
● The air conditioning is manually switched on.
If the bonnet is not fully closed, a warning message is displayed in the
Driver Information Centre.
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.
● Always apply the parking brake. Pull switch m for
approx. one second and check
if the control indicator m
illuminates.
The electric parking brake is applied when control indicator
m illuminates 3 99.
● Switch off the engine. ● If the vehicle is on a level surface or uphill slope, engage
first gear or set the selector
lever to position P before
removing the ignition key or
switching off ignition on
vehicles with power button. 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 before removing the ignition
key or switching off ignition on
vehicles with power button.
Turn the front wheels towards
the kerb.
● Close the windows and the sunroof.
● Remove the ignition key from the ignition switch or switch off
ignition on vehicles with power
button. Turn the steering wheel
until the steering wheel lock is
felt to engage.
For vehicles with automatic
transmission, the key can only
be removed when the selector
lever is in position P.
●
Lock the vehicle with button e on
the radio remote control.
Activate the anti-theft alarm
system 3 30.
● The engine cooling fans may run
after the engine has been
switched off 3 231.
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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 even in manual 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 3 115.
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
3 264.
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 below the selector lever
and push the trim upwards.
Rotate trim to the left.