
To maintain the proper distance to the vehicle
in front of you and thus prevent a rear-end
collision, you must apply the brakes yourself.XBrake the vehicle immediately to avoid a
collision.
Under no circumstances should the driver
await the intermittent warning sound
before braking. Observe the following
warning note.
The intermittent warning sound ceases and
the distance warning lamp · goes out
when the necessary distance to the vehicle
ahead is again established.
The PRE-SAFE ®
Brake can react to stationary
obstacles such as standing or parked vehicles
at road speeds of up to approximately 40 mph
(70 km/h).
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.
The PRE-SAFE ®
Brake does not always clearly
interpret complex traffic situations. If a visual
and/or acoustic warning is issued in an
uncritical driving situation, or if the vehicle
brakes lightly, you can interrupt the PRE-
SAFE ®
Brake maneuver by pressing down all
the way on the accelerator pedal, using
kickdown, or releasing the brake pedal.
The PRE-SAFE ®
Brake maneuver is
terminated immediately when
R you avoid the obstacle by evasive steering
R you drive less than 9 mph (15 km/h)
R an obstacle can no longer be identified
ahead of you
R the system no longer senses the risk of a
collision
i The PRE-SAFE ®
Brake will remain passive
while DISTRONIC PLUS is switched on
( Y page 149).
After a hard collision or damage to the front
of the vehicle from an accident, have the
settings and operation of the radar sensors
checked by an authorized Mercedes-Benz
Center.XActivating and deactivating: Activate or
deactivate the PRE-SAFE ®
Brake using the
instrument cluster control system
( Y page 137).
After the function has been activated, the
PRE-SAFE ®
Brake indicator Ä appears
in the instrument cluster. When the HOLD
function is switched on, the PRE-SAFE ®
Brake indicator Ä will not appear.
In vehicles with Parking Guidance, the
automatic transmission must be in park
position P for the PRE-SAFE ®
Brake
indicator Ä to be displayed.
The PRE-SAFE ®
Brake is deactivated when
the radar system is switched off. When you
switch off the radar system, the following
functions are deactivated:
R PRE-SAFE ®
Brake
R BAS PLUS ( Y page 63)
R DISTRONIC PLUS ( Y page 149)
R Blind Spot Assist ( Y page 175)
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
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ActivatingXWith SmartKey: Remove the SmartKey
from the starter switch.
XWith KEYLESS-GO: Turn off the engine and
open the driver’s door.
Deactivating
XSwitch on the ignition.
iStarting the engine will also deactivate
the immobilizer.
In the event that the engine cannot be
started (yet the vehicle’s battery is
charged), the system is not operational.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada).
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
Ra door
Rthe trunk
Rthe hood
The alarm will stay on even if the activating
element, a door, for example, is closed
immediately.
The alarm system will also be triggered when
Rthe vehicle is opened with the mechanical
key
Ra door is opened from the inside
Rthe trunk is opened with the emergency
release button
To cancel the alarm after it has been
triggered, see “Canceling the alarm”
(Y page 73).
iIf the alarm stays on for more than
30 seconds, the Tele Aid system initiates a
call to the Customer Assistance Center
automatically. The Tele Aid system will
initiate the call provided that
Ryou have subscribed to the Tele Aid
service
Rthe Tele Aid service has been activated
properly
Rthe necessary mobile phone, power
supply and GPS coverage are available
XArming: Lock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash three times and
an acoustic warning sounds three times to
indicate that the vehicle is locked. Indicator
lamp : flashes to indicate that the alarm
system is armed.
iIf the turn signal lamps do not flash three
times and the acoustic warning does not
sound three times, a door or the trunk may
not be properly closed.
Close the respective element.
XDisarming: Unlock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash once and an
acoustic warning sounds once to indicate
that the alarm system is disarmed.
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iCanada 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.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Important notes on using KEYLESS-GO
R You can also use the SmartKey with
KEYLESS-GO like a normal SmartKey
( Y page 76).
R You can combine KEYLESS-GO functions
with normal SmartKey functions (e.g.
unlocking with KEYLESS-GO and locking
with button &).
R Always carry the SmartKey with you.
R Never store the SmartKey together with
- electronic items such as a mobile phone
or another SmartKey
- metallic objects such as coins or metal
foil
Doing so could impair the function of the
KEYLESS-GO system.
R To lock or unlock the vehicle, the SmartKey
must be located outside the vehicle within
approximately 3 ft (1 m) of a door or the
trunk.
R When the vehicle has been parked for more
than 72 hours, the KEYLESS-GO function is
deactivated. Pull an outside door handle
and switch on the ignition once to activate
the KEYLESS-GO function.
R If the SmartKey is positioned farther away
from the vehicle, the system may no longer
recognize the SmartKey. The vehicle
cannot be locked or the engine started via
the KEYLESS-GO system.
R If the SmartKey is removed from the vehicle
(e.g. if a passenger exits the vehicle with
the SmartKey)
- when pressing the KEYLESS-GO start/
stop button or trying to lock the vehicle
with the outside door handle the
message Key Not Detected appears in
the multifunction display
- with the engine running, the red message
Key Not Detected appears in the
multifunction display while driving off
Find the SmartKey or change its present
location immediately (e.g. place it on the
front passenger seat or insert it in shirt
pocket).
R If you have started the engine with the
KEYLESS-GO start/stop button, you can
turn it off again by
- pressing the KEYLESS-GO start/stop
button
- inserting the SmartKey into the starter
switch when the vehicle is at a standstill
and the automatic transmission is in park
position P
R The vehicle could be inadvertently
unlocked if the SmartKey is within 3 ft (1 m)
of the vehicle and
- an outside door handle is splashed with
water
or
- you attempt to clean an outside door
handle
R Remember that the engine can be started
by anyone with a SmartKey that is left
inside the vehicle.
Possibility 1 (One SmartKey in the vehicle,
one SmartKey outside the vehicle):
If you leave the SmartKey behind when
exiting and locking the vehicle, no message
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out when the vehicle is pushed or towed or is
on a test stand.
XSwitching off: Press and hold central
unlocking switch : until an acoustic signal
sounds.
XSwitching on: Press and hold central
locking switch ; until an acoustic signal
sounds.
iIf you press and hold either switch and no
acoustic signal sounds, the respective
setting has already been selected.
iYou can also switch on or off the
automatic central locking using the control
system (Y page 144).
Locking and unlocking from the inside
GObserve Safety notes, see page 56.
You can lock or unlock the vehicle from the
inside using the central locking or unlocking
switch. This can be useful, for example, if you
want to lock the vehicle before starting to
drive.
The central locking or unlocking switch does
not lock or unlock the fuel filler flap.
XLocking: Press central locking switch ;.
When all doors are closed, the vehicle
locks.
XUnlocking: Press central unlocking
switch :.
You can open a locked front door from the
inside. Open door only when conditions are
safe to do so.
If the vehicle was previously locked with the
central locking switch
Rand the SmartKey is set to factory settings,
the complete vehicle is unlocked when a
front door is opened from the inside
Rand the SmartKey is set to selective
settings, only the front door opened from
the inside is unlocked
If the vehicle has been locked centrally with
the SmartKey or with KEYLESS-GO, it will not
unlock using the central unlocking switch.
Opening the trunk
GWarning!
Make sure the trunk is closed when the engine
is running and while driving. Among other
dangers, deadly carbon monoxide (CO) gases
may enter vehicle interior resulting in
unconsciousness and death.
! When you open the trunk, the trunk lid
swings open upwards. Always make sure
there is sufficient overhead clearance.
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You can open the trunk when the vehicle is
stationary.
A minimum height clearance of 5.78 ft
(1.76 m) is required to open the trunk lid.
Opening the trunk from the outside
XPress and hold button F (Y page 76) on
the SmartKey until the trunk unlocks and
begins to open.
or
XPull on handle :.
In vehicles without KEYLESS-GO: The
vehicle must be unlocked.
If the trunk does not open, it is still locked
separately (Y page 85).
Opening the trunk from the inside
Example illustration: Vehicles with trunk opening/closing system
XPull remote trunk opening switch : until
the trunk begins to open.
If the trunk does not open, it is still locked
separately (Y page 85).
Closing the trunkGWarning!
Make sure the trunk is closed when the engine
is running and while driving. Among other
dangers, deadly carbon monoxide (CO) gases
may enter vehicle interior resulting in
unconsciousness and death.
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.
GObserve Safety notes, see page 56.
Do not leave the SmartKey in the open trunk.
You may lock yourself out.
If the vehicle was previously locked centrally
with the SmartKey or KEYLESS-GO, the trunk
lid will lock automatically when closed. All
turn signal lamps flash three times and an
acoustic signal sounds three times to confirm
locking.
Closing the trunk from the outside
manually
XLower trunk lid by pulling on handle : or
handle ; firmly.
XClose trunk with hands placed flat on trunk
lid.
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The emergency release button does not open
the trunk, if the vehicle battery is discharged
or disconnected.
Valet locking
You can lock the trunk separately with the
mechanical key. This denies unauthorized
access to the trunk, e.g. when you valet park
the vehicle.
XLeave only the SmartKey less its
mechanical key with the vehicle.
XValet locking: Close the trunk.XRemove the mechanical key from the
SmartKey (Y page 315).
XInsert the mechanical key in the trunk lid
lock.
XTurn the mechanical key clockwise to
position 2 and remove the mechanical
key in that position to lock the trunk.
The trunk remains locked even when the
vehicle is centrally unlocked.
You can then only open the trunk with the
mechanical key.
XCanceling: Insert the mechanical key in
the trunk lid lock.
XTurn the mechanical key counterclockwise
to neutral position 1 and remove the
mechanical key in that position to unlock
the trunk.
You can now open the trunk.
Starter switch positions
SmartKey
GObserve Safety notes, see page 56.gFor removing SmartKey (gear selector
lever must be in park position P)
1Power supply for some electrical
consumers, e.g. wipers
2Ignition (power supply for all electrical
consumers) and driving position
3Starting position
When you switch on the ignition, all lamps in
the instrument cluster come on. The low-
beam headlamp indicator lamp, high-beam
headlamp indicator lamp, turn signal
indicator lamps, and the indicator lamps for
the fog lamps will only come on if activated.
If a lamp in the instrument cluster fails to
come on when the ignition is switched on,
have it checked and replaced if necessary. If
a lamp in the instrument cluster remains on
after starting the engine or comes on while
driving, refer to “Lamps in instrument cluster”
(Y page 304).
If the SmartKey is left in starter switch
position 0 for an extended period of time, it
can no longer be turned in the starter switch.
In this case, the steering is locked. To unlock,
remove SmartKey from the starter switch and
reinsert.
The steering is locked when the SmartKey is
removed from the starter switch.
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XAlways remove the SmartKey from the
starter switch when the engine is not in
operation.
This will help to prevent accelerated vehicle
battery discharge or a completely
discharged vehicle battery.
If the SmartKey cannot be turned in the
starter switch, the vehicle battery may not be
sufficiently charged.
XCheck the vehicle battery and charge it if
necessary (Y page 337).
or
XGet a jump start (Y page 338).
iIf the SmartKey does not belong to the
vehicle, the SmartKey can be turned in the
starter switch. However, the ignition does
not switch on and the engine does not start.
KEYLESS-GO
GObserve Safety notes, see page 56.
Vehicles equipped with the KEYLESS-GO
feature are supplied with a SmartKey with
integrated KEYLESS-GO function and a
removable KEYLESS-GO start/stop button.
The KEYLESS-GO start/stop button must be
inserted in the starter switch and the
SmartKey present in the vehicle.
Pressing the KEYLESS-GO start/stop button
without depressing the brake pedal
corresponds to the various starter switch
positions (Y page 85).
Pressing the KEYLESS-GO start/stop button
with the brake pedal firmly depressed will
start the engine (Y page 109).
The KEYLESS-GO start/stop button can be
pulled out of the starter switch easily. You can
then insert the SmartKey into the starter
switch.
iThe KEYLESS-GO start/stop button does
not need to be removed from the starter
switch when you leave the vehicle.
However, always take the SmartKey with
you when you leave the vehicle. As long as
the SmartKey is in the vehicle, the vehicle’s
electrical systems can be switched on or
the engine can be started using the
KEYLESS-GO start/stop button.
:KEYLESS-GO start/stop button;Starter switchXInsert the KEYLESS-GO start/stop button
into the starter switch (if not inserted
already).
iAllow for 2 seconds until the system has
detected the KEYLESS-GO start/stop
button.
XMake sure the automatic transmission is in
park position P.
XDo not depress the brake pedal.
KEYLESS-GO start/stop button
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Position 0
Before you press the KEYLESS-GO start/stop
button, the vehicle’s on-board electronics
have status 0 (as with SmartKey removed).
Position 1
XPress the KEYLESS-GO start/stop button
once.
This supplies power for some electrical
consumers, e.g. wipers.
i When you now open the driver’s door, the
power supply is switched off.
Ignition (or position 2)
XPress the KEYLESS-GO start/stop button
twice.
This supplies power for all electrical
consumers.
When you switch on the ignition, all lamps
in the instrument cluster come on. The low-
beam headlamp indicator lamp, high-beam
headlamp indicator lamp, turn signal
indicator lamps, and the indicator lamps for
the fog lamps will only come on if activated.
If a lamp in the instrument cluster fails to
come on when the ignition is switched on,
have it checked and replaced if necessary.
If a lamp in the instrument cluster remains
on after starting the engine or comes on
while driving, refer to “Lamps in instrument
cluster” ( Y page 304).
i
When you now press the KEYLESS-GO
start/stop button once and the driver’s
door is open, the power supply is switched
off.
Seats
Safety notes
GWarning!
In order to avoid possible loss of vehicle
control the following must be done before the
vehicle is put into motion:
R seat adjustment
R head restraint adjustment
R steering wheel adjustment
R rear view mirror adjustment
R fastening of seat belts
GWarning!
Do not adjust the driver’s seat while driving.
Adjusting the seat while driving could cause
the driver to lose control of the vehicle.
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. That could cause serious
or fatal injuries. The seat backrest and seat
belts provide the best restraint when the
wearer is in a position that is as upright as
possible and seat belts are properly
positioned on the body.
GWarning!
Your seat must be adjusted so that you can
correctly fasten your seat belt.
Observe the following points:
R Adjust the seat backrest until your arms are
slightly angled when holding the steering
wheel.
R Adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely. The
position should be as far back as possible
with the driver still able to operate the
controls properly.
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