
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision,
you must apply the brakes yourself.
X To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer ( Y page 218).
When PRE-SAFE ®
Brake is activated, the
Ä symbol appears in the multifunction
display, as long as the HOLD function is
deactivated (Y
page 178). On vehicles with
the Active Parking Assist driving system,
the Ä symbol is displayed when position
P is engaged or you are driving faster than
22 mph (35 km/h).
For PRE-SAFE ®
Brake to assist you when
driving, the radar sensor system must be
switched on (Y page 223) and be
operational.
Following damage to the front end of the
vehicle,
have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
i USA only: This device has been approved
by the FCC as a "Vehicular Radar System".
The radar sensor is intended for use in an
automotive radar system only. Removing,
altering or tampering with the device will
void any warranties, and is not permitted
by the FCC. Do not tamper with, alter, or
use the device in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
i Canada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not permitted. Do not tamper with, alter, or use
the device in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Theft deterrent locking system
Immobilizer
X To activate with the SmartKey: remove
the SmartKey from the ignition lock.
X To activate with KEYLESS-GO:
switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle.
Anyone can start the engine if a valid
SmartKey has been left inside the vehicle.
i The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center
or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada). ATA (anti-theft alarm system)Theft deterrent locking system
71
Safety Z

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible.
Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).SmartKey
Important safety notes
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint
system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very hot, and a child could be burned on these
parts.
G
WARNUNG
If a key ring is too heavy or too large, the
weight
acting on the SmartKey could cause it
to turn in the ignition lock or catch on the
steering wheel. This could cause the engine
to be switched off suddenly. You could lose
control of the vehicle and cause an accident.
Do not attach any heavy or large key rings to
the SmartKey that is inserted in the ignition.
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
The Product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment. 74
SmartKey
Opening/closing

The Product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
R Do not keep the SmartKey:
-with electronic devices, e.g. a mobile
phone or another SmartKey
- with
metallic objects, e.g. coins or metal
foil
- inside metallic objects, e.g. a metal case
This can affect the SmartKey's
functionality.
Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected. SmartKey functions
:
& To lock the vehicle
; F To unlock the trunk lid
= % To unlock the vehicle
X To unlock centrally: press the %
button.
If you do not open the vehicle within
approximately
40 seconds of unlocking:
R the vehicle is locked again.
R the theft deterrent locking system is
armed again.
X To lock centrally: press the & button.
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid
R the fuel filler flap When unlocking, the turn signals flash once.
When locking, they flash three times.
You
can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (Y page 222).
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 221). KEYLESS-GO
General notes Bear in mind that the engine can be started
by any of the vehicle occupants if there is a
KEYLESS-GO key in the vehicle.
Locking and unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO.
To do this, you only need carry
the SmartKey with you. When you touch the
surface of the sensors on the vehicle's
outside door handles, KEYLESS-GO
establishes a radio connection between the
vehicle and the SmartKey. When the engine
is started and whilst you are driving,
KEYLESS-GO also checks whether a valid
SmartKey is in the vehicle by periodically
establishing radio contact.
You can combine the KEYLESS-GO functions
with those of a conventional key, e.g. using
KEYLESS-GO to unlock and pressing the
& button to lock.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the
corresponding door handle must not be
greater than 3 ft (1 m). SmartKey
75
Opening/closing Z

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.SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and caustic
substances. For this reason, keep batteries
out of the reach of children.
If
a battery has been swallowed, seek medical
help immediately. G
WARNING
The SmartKey batteries contain perchlorate
material, which may require special handling and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
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 77).
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 in 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 76). SmartKey
77
Opening/closing Z

:
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.
X Make sure that the surface of the battery is
free
from lint, grease and all other forms of
contamination. X
Insert the front tabs of battery
compartment cover : into the housing
first and then press to close it.
X Insert mechanical key ; into the
SmartKey (Y page 76).
X Check the function of all SmartKey buttons
on the vehicle.78
SmartKey
Opening/closing

Problem Possible causes/consequences and
M SolutionsThe 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 316).
or
X Jump-start the vehicle (Y page 317).
or
X Consult a qualified specialist workshop. The engine cannot be
started
using KEYLESS-
GO. The SmartKey is in
the vehicle. A door is open. Therefore, the SmartKey cannot be detected as
easily.
X
Close the door 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
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint
system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function. If children open a door, they could cause
severe
or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger
compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident80
Doors
Opening/closing

Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked.
You
can only open the rear doors from inside
the vehicle if they are not secured by the
child-proof locks (Y page 63). X
Pull door handle ;.
If
the door is locked, locking knob : pops
up. The door is unlocked and can be
opened. Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. X
To unlock: press button :.
X To lock: press button ;.
If
all the doors are closed, the vehicle locks.
You cannot unlock the vehicle centrally from
the
inside if the vehicle has been locked with
the SmartKey or KEYLESS-GO. The central locking/unlocking button does
not lock or unlock the fuel filler flap.
You can open a front door from inside the
vehicle even if it has been locked.
If the vehicle has been locked using the
locking button for the central locking, or has
been locked automatically, and a door is
opened from the inside:
R
the vehicle will be fully unlocked if it had
previously been fully unlocked
R only
the door which has been opened form
the inside is unlocked if only the driver's
door had been previously unlocked Automatic locking feature
X
To deactivate: press and hold button :
for
about five seconds until a tone sounds.
X To activate: press and hold button ; for
about five seconds until a tone sounds.
i If you press one of the two buttons and
do
not hear a tone, the relevant setting has
already been selected.
The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning.
You could therefore lock yourself out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is on a roller dynamometer.
You can also switch the automatic locking
function on and off using the on-board
computer (Y page 222). Doors
81
Opening/closing Z

G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint
system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger
compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid. i
Opening dimensions of the trunk lid
(Y page 371).
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
Vehicles
without trunk lid remote closing
feature: the trunk lid can be:
R opened and closed manually from outside
R opened automatically from outside
R opened automatically from inside
R locked separately
R unlocked with the mechanical key
R opened with the emergency release button
Vehicles with trunk lid remote closing
feature: the trunk lid can be:
R opened and closed manually from outside
R opened and closed automatically from
outside
R opened and closed automatically from
inside
R locked separately
R unlocked with the mechanical key
R opened with the emergency release button Opening/closing from outside
Opening X
Press the % button on the SmartKey.
X Pull handle :. Trunk
83
Opening/closing Z