
approximately six seconds until the battery
check lamp flashes twice (Y page 85).
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the &or% button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
% button once.
X To unlock centrally: press the%
button twice.
X To lock centrally: press the&button.
The KEYLESS-GO function is changed as
follows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press
and hold down the %and& buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice ( Ypage 85). Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey, use the
mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid/
tailgate, the anti-theft alarm system will be
triggered (Y page 78). There are several ways to turn off the alarm:
X
To turn the alarm off with the
SmartKey: press the%or& button
on the SmartKey.
or
X Insert the SmartKey into the ignition lock.
or
X To disarm the alarm with KEYLESS-GO:
press the Start/Stop button in the ignition
lock. The SmartKey must be in the vehicle.
or
X Lock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key :
Release catch
; Mechanical key
X Push release catch :in the direction of
the arrow and at the same time remove
mechanical key ;from the SmartKey.
For further information about:
R unlocking the driver's door (Y page 90)
R unlocking the trunk (Y page 97)
R unlocking the tailgate (Y page 97)
R locking the vehicle (Y page 90)84
SmartKeyOpening and closing
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SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive
substances. If batteries are swallowed, it can
result in severe health problems. There is a
risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop.
Checking the battery X
Press the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
X Change the battery (Y page 85).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the &or% button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified
specialist workshop. Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 84). :
Battery compartment cover
; Mechanical key
X Press mechanical key ;into the opening
in the SmartKey in the direction of the
arrow until battery compartment cover :
opens. Do not hold battery compartment
cover :closed while doing so.
X Remove battery compartment cover :. =
Battery
X Repeatedly tap the SmartKey against your
palm until battery =falls out.
X Insert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so. SmartKey
85Opening and closing Z
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Problems with the SmartKey
Problem Possible causes/consequences and
M
MSolutions You can no longer lock
or unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Check the SmartKey battery (Y page 85) and replace it if
necessary (Y page 85).
If this does not work:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You can no longer lock
or unlock the vehicle
using KEYLESS-GO. The SmartKey battery is discharged or nearly discharged.
X
Check the SmartKey battery (Y page 85) and replace it if
necessary (Y page 85).
If this does not work:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. There is interference from a powerful source of radio waves.
X
Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. KEYLESS-GO is malfunctioning.
X
Lock/unlock the vehicle using the remote control function of
the SmartKey.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote
control function:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. You have lost a
SmartKey. X
Have the SmartKey deactivated at a qualified specialist
workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. SmartKey
87Opening and closing Z
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Problem Possible causes/consequences and
M
MSolutions You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 360).
or
X Jump-start the vehicle (Y page 362).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked.
X
Unlock the vehicle and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the vehicle. Always keep the SmartKey out of
reach of children.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
Ideally, place luggage or loads in the trunk/
cargo compartment. Observe the loading
guidelines (Y page 298). Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked. If the vehicle has
been locked with the SmartKey or with
KEYLESS-GO, opening a door from the inside 88
DoorsOpening and closing
ProCarManuals.com

SmartKey
Display messages Possible causes/consequences and
M
MSolutions Â
Key Does Not Key Does Not
Belong to Vehicle Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. Â
Take Take
Your
YourKey
Keyfrom
from
Ignition
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. Â
Obtain a New Key Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. Â
Replace Replace
Key
KeyBattery
Battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 85).Â
Don't Forget Your Don't Forget Your
Key Key The display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X
Remember to take the KEYLESS-GO key with you when you
leave the vehicle. Â
Key Not Detected Key Not Detected
(red display message) The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).
X Operate the vehicle with the SmartKey in the ignition lock. 284
Display messagesOn-board computer and displays
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