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20Keys, doors and windowsBattery replacement in the electronic
key 3 17.
Electronic key synchronisation
The electronic key synchronises itself automatically during every starting
procedure.
Fault
If the central locking cannot be
operated or the propulsion system
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 20.Memorised settings
Whenever the ignition is switched off, some functions of the following
settings may be automatically
memorised by the remote control unit
or the electronic key:
● automatic climate control
● lighting
● Infotainment system
● central locking system
● comfort settings
The saved settings are automatically
used the next time the vehicle is
switched on with the memorised
electronic key 3 19.
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.
Vehicle personalisation 3 90.Central locking system
Unlocks and locks doors and load
compartment.
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.
Note
A short time after unlocking with the
remote control the doors are locked
automatically if no door has been
opened. A precondition is that the
setting is activated in the vehicle
personalisation 3 90.
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Keys, doors and windows31Electronic key system: Unlocking the
vehicle by pressing the button on any
exterior door handle deactivates the
anti-theft alarm system.
The electronic key must be outside
the vehicle, within a range of approx.
1 m of the relevant door side.
The system is not deactivated by
unlocking the driver's door with the
key or with the central locking button
in the passenger compartment.
AlarmWhen triggered, the alarm horn
sounds and the hazard warning lights
flash simultaneously. The number
and duration of alarm signals are
stipulated by legislation.
The anti-theft alarm system can be
deactivated by pressing (, by
pressing the button on the door
handle or switching on the vehicle.
A triggered alarm, which has not been interrupted by the driver, will be
indicated by the hazard warning
lights. They will flash quickly three
times the next time the vehicle is
unlocked with the radio remote
control. Additionally, a warningmessage is displayed in the Driver
Information Centre after switching on
the vehicle.
Vehicle messages 3 89.
Immobiliser The system is part of the ignition
switch and checks whether the
vehicle is allowed to be started with the key being used.
The immobiliser is activated
automatically after the electronic key
has been removed from the vehicle.
If control indicator d flashes when the
vehicle is on, there is a fault in the
system. The propulsion system
cannot be started. Switch off the
vehicle and repeat the start attempt.
If control indicator d continues
flashing, attempt to start the
propulsion system using the spare
key and seek the assistance of a
workshop.Note
Radio Frequency Identification
(RFID) tags may cause interference
with the key. Do not have it placed near the key when starting the
vehicle.
Note
The immobiliser does not lock the doors. You should always lock the
vehicle after leaving it and switch on the anti-theft alarm system 3 20,
3 30.
Control indicator d 3 81.
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170Driving and operatingnot brake outside of its operatingspeed range and only responds to
detected vehicles.
Forward looking brake assist
In addition to the brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. Therefore,
depressing the brake pedal less
strongly results in immediate hard
braking. This function helps the driver
brake quicker and harder before an
imminent collision.
The system operates up to a speed of 80 km/h.
9 Warning
Active emergency braking is not
designed to apply hard
autonomous braking or to
automatically avoid a collision. It is designed to reduce the vehicle
speed before a collision. It may not
react to animals. After a sudden
lane change, the system needs a
certain time to detect the next
preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the brakes and steer to avoid
collisions.
Intelligent brake assist
Intelligent brake assist may activate
when the brake pedal is applied
quickly by providing a boost to
braking based on the speed of
approach and distance to a vehicle
ahead.
Minor brake pedal pulsations or pedal movement during this time are normal and the brake pedal should continue
to be applied as required. Intelligent
brake assist will automatically
disengage only when the brake pedal is released.
9 Warning
Intelligent brake assist may
increase vehicle braking in
situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
Front pedestrian protection
Front pedestrian protection 3 171.
Deactivation Active emergency braking can be
deactivated in the personalisation
menu in the Info Display 3 90.
If deactivated, a message is
displayed in the Driver Information
Centre.
We recommend to deactivate the system in the following cases:
● when the vehicle is being towed
● before using an automatic car wash with ignition switched on