
Immediately brake your vehicle to increase
the distance between your vehicle and the
vehicle driving in front of you. The warning
sound is intended as a final caution that you
have not interceded with your own braking
inputs to avoid a potentially dangerous
situation. Do not wait for the operation of the
warning signal to intercede with your own
braking, as that will result in potentially
dangerous emergency braking which will not
always result in an impact being avoided.
Tailgating increases the risk of an accident.GWarning!
The PRE-SAFE ®
Brake is a convenience
system designed to assist the driver during
vehicle operation. The responsibility for the
vehicle speed and the distance to the vehicle
ahead, including most importantly brake
operation to assure safe stopping distance,
always remains with the driver.
Always pay attention to traffic conditions
even while the PRE-SAFE ®
Brake is switched
on. Otherwise, you may not be able to
recognize dangerous situations until it is too
late and could cause an accident resulting in
personal or fatal injury to you or others.
i USA only: this device has been approved
by the FCC as a "Vehicular Radar System".
The radar sensor system is intended for use
in an automotive radar system only.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted by the FCC. Do not tamper with
the device in any 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 from Industry Canada. Operation
is subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must withstand any
interference received, including
interference that may cause undesired
operation.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. Do not tamper with the device
in any way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
With the help of the radar sensor system,
PRE-SAFE ®
Brake can detect obstacles that
are in front of your vehicle for an extended
period of time. If you approach an obstacle
and PRE-SAFE ®
Brake detects a risk of a
collision, the system will initially alert you
both visually and acoustically. If you do not
brake or steer, the vehicle will at first
automatically brake slightly. In the event of
an increased risk of a collision, PRE-SAFE ®
is
activated ( Y page 51). If the risk of collision
remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking.GWarning!
The PRE-SAFE ®
Brake will only respond with
brake assistance if it has clearly detected an
object. Detection can be impeded by:
R dirty or covered sensors
R snowfall or heavy rain
R disturbance from other radar sources
R strong radar reflection such as in parking
garages
The PRE-SAFE ®
Brake uses radar signals that
are not reflected well by narrow objects and
absorptive materials. For this reason the PRE-
SAFE ®
Brake will not react to persons,
animals, and approaching traffic or cross-
traffic.
The PRE-SAFE ®
Brake may not detect narrow
vehicles driving in front of you, such as
motorcycles and vehicles driving offset from
your vehicle center.
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GWarning
Depending on the vehicle speed, PRE-SAFE®
Brake brakes your vehicle with a maximum of
13 ft/s 2
(4 m/s 2
) before a possible hard stop.
This corresponds to about 40 % of the
maximum deceleration ability of your vehicle.
The driver must apply the brakes additionally
in order to prevent a collision. The self-acting
hard stop will be initiated when the imminent
danger of a collision exists, e.g. when an
evasive maneuver cannot avoid an accident.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
At speeds up to approximately
40 mph (70 km/h), PRE-SAFE ®
Brake can
also detect stationary obstacles, for example
stopped or parked vehicles.
GWarning!
If you do not receive visual or acoustic
warning signals, the PRE-SAFE ®
Brake may
R not have recognized the collision risk
R have been deactivated
R be malfunctioning
Apply the brakes yourself to avoid a collision.
XTo activate: activate PRE-SAFE ®
Brake in
the on-board computer ( Y page 207).
The Ä symbol appears in the lower
multifunction display, as long as the HOLD
function is not activated ( Y page 184).
On vehicles with parking guidance, the P
gear must be engaged for the icon to be
displayed.
For PRE-SAFE ®
Brake to assist you when
driving, the radar sensor system must be
switched on and operational.
PRE-SAFE ®
Brake does not always detect
complex traffic situations properly. You can
terminate the braking action of PRE-SAFE ®
Brake in a non-critical driving situation at any
time if:
R an acoustic and visual warning occurs
R the vehicle brakes
To end this, you can either depress the
accelerator pedal further, activate kickdown
or release the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle
R you drive slower than approximately
9 mph (15 km/h)
R there is no longer an obstacle detected in
front of your vehicle
R there is no longer any danger of a collision
Following a collision or accident-related
damage to the front end of the vehicle, have
the configuration and operation of the radar
sensors checked. Choose a qualified
specialist workshop for this which has the
necessary specialist knowledge and tools for
the work required. Mercedes-Benz
recommends that you use an authorized
Mercedes-Benz Center for this purpose.
Anti-theft systems
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct key.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
key that is left inside the vehicle.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.XTo deactivate: switch on the ignition.70Anti-theft systemsSafety
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
SmartKey
Important safety notes
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned by these
parts.
GWarning!
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
General information
If the SmartKey is faulty, contact Roadside
Assistance or an authorized Mercedes-Benz
Center.
SmartKey functions
Locking and unlocking centrally
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid
R the fuel filler flap
:& To lock the vehicle;F To unlock the trunk lid/tailgate=% To unlock the vehicle
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 or unlocked.
The audible signal can be activated and
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Changing the settings of the locking
system
You can change the settings of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.XTo change the setting: press the %
and & buttons simultaneously for
approximately six seconds until the battery
check lamp flashes twice.
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.XTo unlock centrally: press the %
button twice.XTo lock centrally: press the & button.
The KEYLESS-GO function is changed as
follows:
XTo unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.XTo unlock centrally: touch the inner
surface of the front-passenger door handle.XTo lock centrally: touch sensor
surface : on one of the door handles.
Restoring the factory settings
XPress the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice.
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, the
anti-theft alarm system will be triggered
( Y page 71).
There are several ways to turn off the alarm:XPress the % or & button on the
SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XPress the Start/Stop button in the ignition
lock. The SmartKey must be in the vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
Removing the mechanical key
XPush release catch : in the direction of
the arrow and at the same time remove
mechanical key ; from the SmartKey.
SmartKey battery
Important safety notes
It is advisable to have batteries replaced at a
qualified specialist workshop, e.g. at an
authorized Mercedes-Benz Center.
GWarning!
Batteries are toxic and contain caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, visit a doctor
immediately.
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GWarning
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government's disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the battery
XPress the & or % button.
The battery is working properly if battery
charge indicator lamp : lights up briefly.
If battery charge indicator lamp : does not
light up briefly during the test, the key
batteries are discharged.
XChange the key battery ( Y page 78).
i
Consult any authorized Mercedes-Benz
Center for a key battery.
i If the battery is tested within the signal
range of the vehicle, you can open or close
the vehicle by pressing & or %
respectively.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 77).XPress mechanical key ; into the opening
in the SmartKey in the direction of the
arrow until battery tray cover : opens. Do
not hold the cover closed while doing so.XRemove the cover of the battery tray.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
pole facing upwards. Use a lint-free cloth to
do so.XInsert the front tabs of the battery tray's
cover first and then press to close it.XCheck the function of all SmartKey buttons
on the vehicle.78SmartKeyOpening and closing
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ProblemPossible causes/consequences and M SolutionsThe SmartKey cannot
be turned in the ignition
lock.The SmartKey has been in position 0 for a considerable time.XRemove the SmartKey and re-insert it into the ignition lock.XCheck the starter battery and charge it if necessary
( Y page 293).XStart the engine.The on-board voltage is too low.XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to turn the SmartKey again.
If this does not work:
XCheck the starter battery and charge it if necessary
( Y page 293).
or
XJump-start the vehicle ( Y page 296).
or
XConsult a qualified specialist workshop.Doors
Important safety notes
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned by these
parts.GWarning!
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
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iWhen you push either of the two buttons
and an audible warning signal does not
sound, the relevant setting has already
been selected.
You can switch the automatic locking
function on and off using the on-board
computer (Y page 210).
Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked
centrally with the SmartKey or KEYLESS-GO:
XTake the mechanical key out of the
SmartKey (Y page 77).
XInsert the mechanical key into the lock of
the driver's door as far as it will go.
XTurn the mechanical key counter-clockwise
to position 1.
The door is unlocked.
XTurn the mechanical key back and remove
it.
Locking the vehicle (mechanical key)
Emergency locking
XOpen the driver's door.XClose the front-passenger door and the
trunk lid.
XPress the locking button (Y page 81).XMake sure that the locking knob on the
front-passenger door is still visible. Press
down the locking knob by hand, if
necessary.
XClose the driver's door.XTake the mechanical key out of the
SmartKey (Y page 77).
XInsert the mechanical key into the lock of
the driver's door as far as it will go.
XTurn the mechanical key clockwise as far
as it will go to position 1.
XTurn the mechanical key back and remove
it.
XMake sure that the doors and the trunk lid
are locked.
iIf you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not activated.
Trunk
Important safety notes
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
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GWarning
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:
Rinjure themselves on vehicle parts
Rbe seriously or fatally injured by extreme
heat or cold
Rinjure 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.
GWarning!
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
Rstrong braking maneuvers
Rsudden changes of direction
Ran accident
GWarning
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
For the trunk lid to be opened fully, there must
be a minimum clearance from floor to ceiling
of 5.58 ft (1.70 m).
The trunk lid can be:
Ropened and closed manually from outside
Ropened automatically from outside
Ropened automatically from inside
Opening and closing manually
Opening
You can only open the trunk lid after
unlocking it first.
You can only unlock the trunk lid when the
vehicle is stationary.
XPress the % button on the SmartKey.XPull handle :.XRaise the trunk lid.
Closing
GWarning
To prevent possible personal injury, always
keep hands and fingers away from the trunk
opening when closing the trunk lid. Be
especially careful when small children are
around.
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