Page 23 of 323
Keys, doors and windows21
The electronic key simply needs to beon the driver's person.
Additionally, the electronic key
includes the functionality of the radio
remote control:
● central locking system● anti-theft alarm system
● power windows
The hazard warning flashers confirm
operation.
Handle the device with care, protect
from moisture and high temperatures
and avoid unnecessary operation.
Note
Do not put the electronic key in the
load compartment.
Replacing battery in electronic
key
Replace the battery as soon as the
system no longer operates properly
or the range is reduced. The need for battery replacement is indicated by a
message in the Driver Information
Centre 3 124.
Batteries do not belong in household
waste. They must be disposed of at
an appropriate recycling collection
point.
To replace:
1. Press button at the back of the electronic key unit and extract thekey blade from the housing.
Page 24 of 323

22Keys, doors and windows2. Insert the key blade again forapprox. 6 mm and turn the key to
open the housing. Further
insertion of the key blade can
damage the housing.
3. Remove and replace battery. Use
CR 2032 or equivalent battery.
Pay attention to the installation
position.
4. Close the housing and insert key blade.
Batteries do not belong in household
waste. They must be disposed of at
an appropriate recycling collection
point.
Fault
If the central locking cannot be
operated or the engine cannot be
started, the cause may be one of the
following:
● Fault in electronic key.
● Electronic key is out of reception range.
● The battery voltage is too low.● Overload of the central locking system by operating at frequent
intervals, the power supply is
interrupted for a short time.
● Interference from higher-power radio waves from other sources.
To rectify the cause of the fault,
change the position of the electronic
key.
Manual unlocking 3 22.
Memorised settings
Whenever the ignition is switched off, the following settings are
automatically memorised by the
electronic key:
● automatic climate control
● lighting
● Infotainment system
● central locking system
● Sport mode settings
● comfort settings
The saved settings are automatically
used the next time the ignition is
switched on with the memorised
electronic key 3 20.A precondition is that Personalisation
by Driver is activated in the personal
settings of the Info-Display. This must
be set for each electronic key which is used. The status change is available
only after locking and unlocking the
vehicle.
The assigned memory position of the
power seat is automatically recalled
when switching on ignition and Auto
Memory Recall is activated in the
Info-Display for the memorised electronic key.
Power seat 3 49.
Vehicle personalisation 3 126.
Central locking system
Unlocks and locks doors, load
compartment and fuel filler flap.
A pull on an interior door handle
unlocks the respective door. Pulling
the handle once more opens the door.
Note
In the event of an accident in which
airbags or belt pretensioners are
deployed, the vehicle is
automatically unlocked.
Page 25 of 323

Keys, doors and windows23Note
A short time after unlocking with the
electronic key, the doors are being
locked automatically if no door has
been opened. A precondition is that
the setting is activated in the vehicle
personalisation 3 126.
Electronic key system operation
The electronic key must be outside
the vehicle, within a range of approx. one metre of the relevant door side.
Unlocking
Press the button on the respective
exterior door handle and pull the
handle.
Unlocking mode can be set in the
vehicle personalisation menu in the
Info-Display. Two settings are
selectable:
● All doors, load compartment and fuel filler flap will be unlocked by
pressing the button on any
exterior handle once.
● Only the driver's door, load compartment and fuel filler flap
will be unlocked by pressing the
button on the driver's door
exterior handle once. To unlock
all doors, press button twice.
The setting can be changed in the
menu Settings in the Info-Display.
Vehicle personalisation 3 126.
Locking
Press the button on any exterior door
handle.
All doors, load compartment and fuel
filler flap will be locked.
Page 26 of 323

24Keys, doors and windowsThe system locks if any of the
following occurs:
● It has been more than five seconds since unlocking.
● The button on an exterior handle has been pressed twice within
five seconds to unlock the
vehicle.
● Any door has been opened and all doors are now closed.
If the driver's door is not closed
properly, the electronic key remains in the vehicle or the ignition is not off,
locking will not be permitted.
If there have been two or more
electronic keys in the vehicle and the
ignition was on once, the doors will be locked even if just one electronic key
is taken out of the vehicle.
Unlocking and opening the tailgate
The tailgate can be unlocked and
opened handsfree via moving the foot below the rear bumper or by pushing
the touchpad switch under the brand
emblem when the electronic key is in
range. The doors remain locked.
Load compartment 3 28.Operation with buttons on the
electronic key
The central locking system can also
be operated with the buttons on the
electronic key.
Unlocking
Press c.Unlocking mode can be set in the
vehicle personalisation menu in the
Info-Display. Two settings are
selectable:
● All doors, load compartment and fuel filler flap will be unlocked by
pressing c once.
● Only the driver's door and fuel filler flap will be unlocked by
pressing c once. To unlock all
doors, press c twice.
Select the relevant setting in Settings,
I Vehicle in the Info-Display.
Info-Display 3 120.
Vehicle personalisation 3 126.
The setting can be saved for the key
being used. Memorised settings
3 22.Locking
Close doors, load compartment and
fuel filler flap.
Press e.
If the driver's door is not closed properly, the central locking system
will not work.
Page 27 of 323
Keys, doors and windows25Passive locking
Automatic locking 3 26.
Confirmation
Operation of central locking system is
confirmed by the hazard warning
flashers. A precondition is that the
setting is activated in the vehicle
personalisation 3 126.
Central locking buttons
Locks or unlocks all doors, the load
compartment and fuel filler flap from
the passenger compartment via a
switch in the driver's door panel.Press e to lock. LED in button
illuminates.
Press c to unlock.
Operation with the key in case of
a central locking system fault
In case of a fault, e.g. vehicle battery
or electronic key battery is
discharged, the driver's door can be
locked or unlocked with the key blade.
Push the button on the electronic key
and pull out the key blade.
The lock cylinder in the driver's door is covered by a cap.
Insert the key blade into the recess at the bottom of the cap and swivel the
key upward.
Manual unlocking
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26Keys, doors and windowsManually unlock the driver's door by
inserting and turning the key blade in
the lock cylinder.
The other doors can be opened by
pulling the interior handle twice or by
pressing c in the driver's door panel.
The load compartment and fuel filler
flap will possibly not be unlocked.
By switching on the ignition, the anti-
theft locking system is deactivated.
Manual locking
Push inside locking knob of all doors
except driver's door or press e in the
driver's door panel. Then close the driver's door and lock it from the
outside by turning the key in the lock
cylinder. The fuel filler flap and
tailgate are possibly not locked.
After locking, cover the lock cylinder
with the cap: insert the cap with the
lower side in the recesses, swivel and
push the cap until it engages at the
upper side.
Automatic locking
Automatic locking after driving off
This security feature can be
configured to automatically lock all
doors, load compartment and fuel
filler flap after driving off and
exceeding a certain speed.
When at a standstill after driving, the
vehicle will be unlocked automatically
as soon as the key is removed from
the ignition switch, or with electronic
key system when the ignition is
switched off.
Activation or deactivation of
automatic locking can be set in the
menu Settings , I Vehicle in the Info-
Display.
Info-Display 3 120.
Vehicle personalisation 3 126.
The setting can be saved for each
electronic key being used 3 22.
Automatic relock after unlocking
This feature can be configured to
automatically lock all doors, load
compartment and fuel filler flap a
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Keys, doors and windows27short time after unlocking with the
remote control or electronic key,
provided no door has been opened.
Activation or deactivation of
automatic relock can be set in the
menu Settings , I Vehicle in the Info-
Display.
Info-Display 3 120.
Vehicle personalisation 3 126.
The setting can be saved for each electronic key being used 3 22.
Passive locking This feature locks the vehicle
automatically after several seconds if
an electronic key has been
recognised previously inside the
vehicle, all doors have then been
closed and the electronic key does
not remain within the vehicle.
If the electronic key remains in the
vehicle or the ignition is not off,
passive locking will not be permitted.
If there have been two or more
electronic keys in the vehicle and the
ignition was on once, the feature
locks the vehicle if just one electronic key is taken out of the vehicle.To prevent passive locking of the
vehicle e.g. when refuelling or if
passengers remain in the vehicle, the
system must be disabled.
To disable the system, press the
central locking button c for a few
seconds while one door is open. An
acoustic signal sounds three times to confirm deactivation. The function
remains disabled until the central
locking button e is pressed or the
ignition is switched on.
Activation or deactivation of passive
locking can be set in the menu
Settings , I Vehicle in the Info-Display.
Info-Display 3 120.
Vehicle personalisation 3 126.
The setting can be saved for each electronic key being used 3 22.Child locks9 Warning
Use the child locks whenever
children are occupying the rear
seats.
Move the pin in the rear door to the front position. The door cannot be
opened from the inside.
To deactivate, move the pin to the
rear position.
Page 30 of 323
28Keys, doors and windowsDoors
Load compartment Tailgate
OpeningGrand Sport
After unlocking, push the brand
emblem and open the tailgate.
Sports Tourer, Country Tourer
After unlocking, push the touchpad
switch under the tailgate moulding
and open the tailgate manually.
Central locking system 3 22.
Closing
Use the interior handle.
Central locking system 3 22.
Power tailgate
9 Warning
Take care when operating the
power tailgate. Risk of injury,
particularly to children.
Keep a close watch on the
movable tailgate when operating.
Ensure that nothing becomes