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GWARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
GWARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
!Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing 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.
SmartKey positions
SmartKey
gTo remove the SmartKey
(shift the transmission to position P)
1Power supply for some consumers, such
as the windshield wipers
2Ignition (power supply for all consumers)
and drive position
3To start the engine
iThe SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart- Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Start/Stop button
General notes
Vehicles with KEYLESS-GO are equipped with
SmartKeys featuring the integrated KEYLESS-
GO function and a detachable Start/Stop but-
ton.
A check which periodically establishes a radio connection between the vehicle and the
SmartKey determines whether a valid Smart-Key is in the vehicle. This occurs, for example,
when starting the engine.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button.
Pressing the Start/Stop button several times
in succession corresponds to the different
key positions in the ignition lock. This is only
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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 immedi-
ately.
To start the vehicle without actively using the
SmartKey:
R the Start/Stop button must be inserted in
the ignition lock.
R the SmartKey must be in the vehicle.
R the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Ypage 71).
Do not keep the KEYLESS-GO key:
R with electronic devices, e.g. a mobile
phone or another SmartKey.
R with metallic objects, e.g. coins or metal
foil.
R inside metallic objects, e.g. a metal case.
This can affect the functionality of KEYLESS-
GO.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time:
R you will not be able to switch on the ignition
with the Start/Stop button.
R you will not be able to start the engine with
the Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the but-
ton on the front door ( Ypage 78), you can
continue to start the engine with the Start/
Stop button.
The engine can be switched off while the vehi-
cle is in motion by pressing and holding the
Start/Stop button for three seconds. This
function operates independently of the ECO
start/stop automatic engine switch-off func-
tion. Key positions with the Start/Stop button
:Start/Stop button
;Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light up. Further information on situations where
an indicator lamp either fails to go out after
starting the engine or lights up while driving( Y page 237).
If Start/Stop button :has not yet been
pressed, this corresponds to the key being
removed from the ignition.
X To switch on the power supply: press
Start/Stop button :once.
The power supply is switched on. You can
now activate the windshield wipers, for
example.
The power supply is switched off again if:
R the driver's door is opened and
R you press Start/Stop button :twice when
in this position
X To switch on the ignition: press Start/
Stop button :twice.
The ignition is switched on.
The ignition is switched off when:
R the driver's door is opened and
R you press Start/Stop button :twice when
in this position
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.
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You can only switch between Start/Stop but-
ton mode and SmartKey operation when the
vehicle is stationary.
You must also engage park position P.
X Remove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take the SmartKey with you when leaving the vehi- cle. As long as the SmartKey is in the vehicle:
R the vehicle can be started using the Start/
Stop button
R the electrically powered equipment can be
operated
Starting the engine
Important safety notes
GWARNING
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.
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
!Do not depress the accelerator when
starting the engine.
General notes
During a cold start, the engine runs at higher
speeds to enable the catalytic converter to
reach its operating temperature. The sound of
the engine may change during this time.
Automatic transmission
X Shift the transmission to position P
( Y page 143).
The transmission position display in the
multifunction display showsP (Y page 143).
When the transmission is in position N, you
can also start the engine with the brake pedal
depressed.
Starting procedure with the SmartKey
To start the engine using the SmartKey
instead of the Start/Stop button, pull the
Start/Stop button out of the ignition lock.
X Turn the SmartKey to position 3
( Y page 135) in the ignition lock and release
it as soon as the engine is running.
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Starting procedure with the Start/Stopbutton
The Start/Stop button can be used to start
the vehicle manually without inserting the
SmartKey into the ignition lock. The Start/
Stop button must be inserted in the ignition
lock and the SmartKey must be in the vehicle. This mode for starting the engine operates
independently of the ECO start/stop auto-
matic engine start function.
You can start the engine if a valid SmartKey isin the vehicle. Switch off the engine and
always take the SmartKey with you when
leaving the vehicle, even if you only leave it for
a short time. Pay attention to the important
safety notes.
X Depress the brake pedal and keep itdepressed.
X Press the Start/Stop button once(Y page 135).
The engine starts.
Pulling away
Automatic transmission
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
Depress the accelerator carefully when pull-
ing away.
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 ( Ypage 205). It is only possible to shift the transmission
from position
Pto the desired position if you
depress the brake pedal. Only then can the
parking lock be deactivated.
If you do not depress the brake pedal, the
DIRECT SELECT lever can still be moved but
the parking lock remains engaged.
At transmission fluid temperatures below Ò 4 ‡ ( Ò20 †), you can only shift out of park
position Pinto another transmission position
when the engine is running.
iUpshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
Information on the automatic release of the
electric parking brake ( Ypage 153).
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 footfrom the brake pedal to the accelerator pedal
and to depress it before the vehicle begins to
roll.
GWARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill startassist.
Hill start assist is not active if: R you are pulling away on a level road or on a
downhill gradient.
R the transmission is in position N.
R the electric parking brake is applied.
R ESP ®
is malfunctioning.
Further information on holding the vehicle
stationary on uphill gradients ( Ypage 146).
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ECO start/stop function
Introduction
The ECO start/stop function switches the
engine off automatically if the vehicle is stop- ped under certain conditions.
The engine starts automatically when the
driver wants to pull away again. The ECO
start/stop function thereby helps you to
reduce the fuel consumption and emissions
of your vehicle.
Important safety notes
GWARNING
If the engine is switched off automatically andyou exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving. There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
:ECO start/stop display (example: color
multifunction display)
If the engine has been switched off automat-
ically by the ECO start/stop function, theè ECO symbol is shown in the multifunc-
tion display.
The stop/start function is automatically acti-
vated each time you start the engine with the SmartKey.
Automatic engine switch-off
If the vehicle is braked to a standstill in Dor N,
the ECO start/stop function switches off the engine automatically. The ECO start/stop function is operational
when:
R the indicator lamp in the ECO button is lit
green.
R the outside temperature is within the range
that is suitable for the system.
R the engine is at normal operating temper-
ature.
R the set temperature for the vehicle interior
has been reached.
R the battery is sufficiently charged.
R the system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R the driver's door is closed and the driver's
seat belt is fastened.
All of the vehicle's systems remain active
when the engine is stopped automatically.
The HOLD function can also be activated if the engine has been switched off automatically. It is then not necessary to continue applying the brakes during the automatic stop phase.
When you depress the accelerator pedal, the
engine starts automatically and the braking
effect of the HOLD function is deactivated.
The engine can be switched off automatically
a maximum of four times (first stop and three subsequent stops) in succession.
Automatic engine start
The engine starts automatically if:
R you switch off the ECO start/stop function
by pressing the ECO button
R in transmission position Dor Nthe brake
pedal is released and the HOLD function is not active
R you depress the accelerator pedal
R you engage reverse gear R
R you move the transmission out of position P
R you unfasten your seat belt or open the
driver's door
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Rthe vehicle starts to roll
R the brake system requires this
R the temperature in the vehicle interior devi-
ates from the set range
R the system detects moisture on the wind-
shield when the air-conditioning system is
switched on
R the battery's condition of charge is too low
Shifting the transmission to position Pdoes
not start the engine
Deactivating/activating the ECO start/
stop function
X To deactivate: press ECO button :.
Indicator lamp ;goes out.
X To activate: press ECO button :.
Indicator lamp ;lights up.
If the indicator lamp on the ECO button is off, the ECO start/stop function has been deac-
tivated manually or as the result of a mal-
function.
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Problems with the engine
ProblemPossible causes/consequences andMSolutions
The engine does not start.The HOLD function or DISTRONIC PLUS is activated.
X Deactivate the HOLD function ( Ypage 170) or DISTRONIC
PLUS ( Ypage 163).
X Try to start the engine again.
The engine does not
start. The starter motor
can be heard.R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
Before attempting to start the engine again: X Turn the key to position 0in the ignition lock.
or
X Press the Start/Stop button repeatedly until all indicator lamps
in the instrument cluster go out.
X Try to start the engine again ( Ypage 137). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts: X Consult a qualified specialist workshop.
The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak or
discharged.
X Jump-start the vehicle ( Ypage 293).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high.
X Allow the starter motor to cool down for approximately two minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.
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ProblemPossible causes/consequences andMSolutions
The engine is not run-
ning smoothly and ismisfiring.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
X Have the cause rectified immediately at a qualified specialistworkshop.
The coolant tempera-
ture gauge shows a
value above 248 ‡
(120 †). The coolant
warning lamp may also
be on and a warning
tone may sound.The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level ( Ypage 273). Observe the warning
notes as you do so and add coolant if necessary.
Automatic transmission
Important safety notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parkingbrake.
Bear in mind that the power transmission
between the engine and the transmission is
interrupted when the engine is switched off. To prevent the vehicle from rolling away:
R when the engine is switched off and the
vehicle is stationary shift the automatic
transmission to park position Pand
R apply the electric parking brake
DIRECT SELECT lever
Overview of transmission positions
jPark position with parking lock
kReverse gear
iNeutral
hDrive
The DIRECT SELECT lever is on the right of the
steering column.
142Automatic transmission
Driving and parking