
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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Opening and closing with the key
Important safety notes
GRisk of injury
Make sure nobody can be trapped or injured
by moving parts such as the soft-top linkage
or soft-top compartment cover when opening
or closing the soft top.
If there is a risk of entrapment, immediately
release the % or & button on the
SmartKey. The soft-top mechanism stops
immediately.
Opening and closing
iThe key must be near the handle of the
driver's door.
XPoint the tip of the SmartKey at the driver's
door handle.
XTo open: press and hold the % button
on the key until the soft top is fully opened.
The Convertible Top in Operation
message appears in the multifunction
display. The seat ventilation is switched on.
The rear side windows open.
XTo close: press and hold the & button
on the key until the soft top is fully closed.
The Convertible Top in Operation
message appears in the multifunction
display. The soft top and the side windows
close.
Closing the soft top manually
If the soft top cannot be closed automatically,
check the following points:
Ris the trunk partition engaged
(Y page 96)?
Rare the head restraints on the rear bench
seats extended?
Ris the trunk lid closed?
Ris the on-board voltage sufficient?
Start the engine if necessary.
If automatic operation still does not work, the
soft top can be closed manually.
This work must be performed by two persons.
iClosing the soft top manually is a
complex, technically demanding process
which requires a great deal of force. Only
close the soft top manually in extreme
emergencies. In these situations, it is
better to get in touch with a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
GRisk of injury
Remove wristwatches and any jewelry such
as rings or bracelets. You could otherwise get
caught, be injured and damage the vehicle.
Always grip the soft top at the indicated
gripping points when closing the soft top
manually. You could otherwise be injured.
XDepress the parking brake.XOpen the side windows.XLower the head restraints (automatically
(Y page 109) or manually (Y page 109)).
XRemove the key from the ignition lock.XOpen the trunk.XTake the two straps out of the vehicle tool
kit (Y page 287).
XTake the Allen key out of the Operator's
Manual wallet and keep it with you.
XTo open the cover on the left hand side
in the trunk: turn rotary catch : counter-
clockwise and fold down cover ;.
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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.
Notes on breaking-in a new vehicle
The first 1000 miles (1500 km)
The more you look after the engine when it is
new, the happier you will be with its
performance in the future.
R Drive at varying vehicle speeds and engine
speeds for the first 1000 miles (1500 km)
for this reason.
R Avoid overstraining the vehicle during this
period, e.g. driving at full throttle.
R Change gear in good time, at the latest
when the tachometer needle is 2
/ 3 of the
way to the red area in the tachometer
display.
R If possible, do not depress the accelerator
pedal past the point of resistance
(kickdown).
R Only select shift ranges 3, 2 or 1 when
driving slowly, e.g. in mountainous terrain.
After 1000 miles (1500 km) you may
gradually bring the vehicle up to full road and
engine speeds.
i Also observe these breaking-in notes
when the vehicle's engine or axle gear have
been replaced.
i Always observe the respective limit
speeds.
Driving
Important safety notes
GWarning
Make sure absolutely no objects are
obstructing the pedals' range of movement.
Keep the driver's footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure the pedals
still have sufficient clearance.
During sudden driving or braking maneuvers
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
GWarning
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
GWarning
It is dangerous to shift the automatic
transmission out of parking position P or
neutral position N if the engine speed is
higher than idle speed. If your foot is not firmly
on the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and when
your right foot is firmly on the brake pedal.
! Warm up the engine quickly. Do not use
the engine's full performance until it has
reached operating temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle
is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
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SmartKey positions
SmartKeygTo remove the SmartKey
(shift the transmission to position P)1Power supply for some consumers, such
as the windshield wipers2Ignition (power supply for all consumers)
and drive position3To start the engine
Once the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. The indicator lamps of the low-beam
headlamps, high-beam headlamps, turn
signal lamps or front fog lamps only light up
if the low-beam headlamps, high-beam
headlamps, turn signal lamps or front fog
lamps are switched on. If an indicator lamp
does not light up when the ignition is switched
on, check it and replace it if necessary. If an
indicator lamp does not go out after starting
the engine or lights up while the vehicle is in
motion, see ( Y page 240).
If the SmartKey is in position 0 in the ignition
lock for an extended period of time, it can no
longer be turned in the ignition lock. The
steering is then locked. To unlock, remove the
SmartKey and reinsert it in the ignition lock.
The steering is locked when you remove the
SmartKey from the ignition lock.
XRemove the SmartKey when the engine is
switched off.
The battery may otherwise discharge.If you cannot turn the SmartKey in the ignition
lock, the vehicle battery may not be charged
sufficiently.XCheck the vehicle battery and charge if
necessary ( Y page 294).
or
XJump-start the vehicle ( Y page 296).
i
The SmartKey can be turned in the
ignition lock even if it is not the correct
SmartKey for the vehicle. The ignition is not
switched on. The engine cannot be started.
KEYLESS-GO
Vehicles with KEYLESS-GO are equipped with
a SmartKey with an integrated KEYLESS-GO
function and a detachable Start/Stop button.
The Start/Stop button must be inserted in the
ignition lock and the SmartKey must be in the
vehicle.
Pressing the Start/Stop button several times
in succession corresponds to the different
key positions in the ignition lock. This is only
the case if you are not depressing the brake
pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts
immediately.
The Start/Stop button can be removed from
the ignition lock. Then you can insert the
SmartKey in the ignition lock.
i You do not have to remove the Start/Stop
button from the ignition lock when you
leave the vehicle. However, you should
always take the SmartKey with you when
leaving the vehicle. The vehicle can be
started with the Start/Stop button and the
electrical equipment can be operated while
the SmartKey is in the vehicle.
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:Start/Stop button;Ignition lockXInsert Start/Stop button : into ignition
lock ;.
i
When you insert Start/Stop button :
into ignition lock ;, the system requires a
detection time of two seconds before you
can use Start/Stop button :.
XShift the transmission to position P.XDo not press the brake pedal.
Start/Stop button
=USA only?Canada onlyXPosition 0: if Start/Stop button : has not
yet been pressed, this corresponds to the
SmartKey being removed from the ignition.XPosition 1: press Start/Stop button :.
You can now activate the windshield
wipers, for example.i If you then open the driver's door when in
this position, the power supply is
deactivated.XPosition 2 (ignition): press Start/Stop
button : twice.
i
If you press Start/Stop button : once
when in this position and the driver's door
is open, the power supply is deactivated
again.
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. The indicator lamps of the low-beam
headlamps, high-beam headlamps, turn
signal lamps or front fog lamps only light up
if the low-beam headlamps, high-beam
headlamps, turn signal lamps or front fog
lamps are switched on. If an indicator lamp
does not light up when the ignition is switched
on, check it and replace it if necessary. If an
indicator lamp does not go out after the
engine is started or if it lights up while the
vehicle is in motion, see ( Y page 240).
Starting the engine
Important safety notes
GWarning
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
! Do not depress the accelerator pedal
when starting the engine.
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Automatic transmissionXShift the transmission to position P.
i
The transmission position display in the
multifunction display shows P.
Starting procedure with the SmartKey
XTurn the SmartKey to position 3 in the
ignition lock (Y page 151) and release it as
soon as the engine is running.
Using KEYLESS-GO to start the engine
GWarning!
As long as the SmartKey is in your vehicle, the
vehicle can be started. Therefore, never leave
children unattended in the vehicle, as they
could otherwise accidentally start the engine.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Do
not leave children unattended in the vehicle,
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.
i The Start/Stop button can be used to
start the vehicle without inserting the
SmartKey in the ignition lock. The
SmartKey must be in the vehicle.
XThe Start/Stop button must be inserted in
the ignition lock.
i To start the engine with the SmartKey
instead of with KEYLESS-GO, remove the
Start/Stop button from the ignition lock.
XDepress the brake pedal and keep it
depressed.XPress the Start/Stop button once
( Y page 151).
The engine starts.Pulling away
Automatic transmissionGWarning
It is dangerous to shift the automatic
transmission out of parking position P or
neutral position N if the engine speed is
higher than idle speed. If your foot is not firmly
on the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and when
your right foot is firmly on the brake pedal.
i It is only possible to shift the transmission
from position P to the desired position if
you depress the brake pedal. Only then is
the selector lever lock released.
XDepress the brake pedal and keep it
depressed.XShift the transmission to position D or R.XWait until the gear change is completed
before pulling away.XRelease the parking brake ( Y page 166).XRelease the brake pedal.XCarefully depress the accelerator pedal.
!
If a warning tone sounds and the
Release Park. Brake message appears
in the instrument cluster, the parking brake
is still applied. Release the parking brake.
i The vehicle locks centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at
any time.
You can also deactivate the automatic
locking feature ( Y page 210).
i Upshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
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Hill start assist
Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient.
It holds the vehicle for a short time after you
have removed your foot from the brake pedal.
This gives you enough time to move your foot
from the brake pedal to the accelerator pedal
and depress it before the vehicle begins to
roll.
GWarning
Never leave the vehicle when it is held by hill
start assist. After approximately one second,
hill start assist will no longer brake your
vehicle and it could roll away.
XTake your foot off the brake pedal.
i Once you have taken your foot off the
brake pedal, the vehicle is held for around
one second.
XPull away.
Hill start assist will not function if:
R you are pulling away on a level road or a
downhill gradient.
R the transmission is in position N.
R the parking brake is applied.
R ESP ®
is malfunctioning.
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