
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 195).
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 254).
or
XJump-start the vehicle ( Y page 256).
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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Problems with the engineProblemPossible causes/consequences and M SolutionsThe 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.XTurn the SmartKey back to position 0 in the ignition lock before
the next attempt to start with the SmartKey.XBefore the next starting attempt with KEYLESS-GO: shut all open
vehicle doors so that the signals from the SmartKey may be
better received.
or
XPull the Start/Stop button out of the ignition.XUse the SmartKey to start the engine, (Y page 131) as external
radio signals cause KEYLESS-GO to malfunction. 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:
XConsult a qualified specialist workshop.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the starter battery is too
weak or discharged.XJump-start the vehicle ( Y page 256).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
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Display messagesPossible causes/consequences and M Solutions+
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 72).+
Don't Forget Your
KeyThe display message is displayed for a maximum of 60 seconds
and is just a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XTake the KEYLESS-GO key with you when leaving the vehicle.+
Key Not Detected
(red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.+
Key Not Detected
(white display
message)The KEYLESS-GO key cannot be detected at present.XChange the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
XChange the location of the key with the KEYLESS-GO functions
in the vehicle.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.+
Key Detected in
VehicleThe KEYLESS-GO key has been detected inside the vehicle during
locking.XRemove the KEYLESS-GO key from the vehicle.194Display messagesOn-board computer and displays
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Never lean over batteries while connecting.
You might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.GWarning
Do not place any metal objects on the battery
as this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First, touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! Switch off the engine and remove the key
before disconnecting the terminal clamps
from the battery. On vehicles with
KEYLESS-GO, make sure that the ignition is
switched off. Check that all the indicator
lamps in the instrument cluster are off. You
may otherwise destroy electronic
components, such as the alternator.
! Like other batteries, the vehicle battery
may discharge over time if you do not use
the vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center. You can also charge the
battery with a charger recommended by
Mercedes-Benz. Contact an authorized
Mercedes-Benz Center for further
information.
The battery, breather hose and cover of the
positive terminal clamp must be installed
securely during operation.
i Remove the key if you park the vehicle
and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing, charging or replacing. Always have
this work performed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
i If the power supply has been interrupted,
e.g. if the battery has been reconnected,
you must carry out the following tasks:
R set the clock ( Y page 171).
R reset the panorama roof with power tilt/
sliding panel ( Y page 87).
R reset the function for automatically
folding the exterior mirrors in/out by
folding the mirrors out once
( Y page 98).
Charging the battery
GWarning
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and cause explosions that may
result in paint damage, corrosion or personal
injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
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Towing and tow-starting
Important safety notes
GWarning
If you tow the vehicle, you must use a rigid
towing bar if:
R the engine will not run.
R there is a malfunction in the brake system.
R there is a malfunction in the power supply
or the vehicle's electrical system.
With the engine not running, there is no power
assistance for the brake and steering
systems. You will then need considerably
more force to steer and to brake and the
brake pedal travel will be longer. If necessary,
depress the brake pedal with maximum force.
Before towing away, make sure that the
steering can be moved and is not locked.
If you tow or tow-start another vehicle, its
weight must not exceed the maximum
permissible gross vehicle weight of your
vehicle.
It is better to have the vehicle transported
than to have it towed.
! You may only tow the vehicle a maximum
distance of 30 miles (50 km). A towing
speed of 30 mph (50 km/h) must not be
exceeded.
For towing distances over 30 miles
(50 km), the vehicle must loaded onto a
transporter.
! Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged.
! Do not use the towing eye for recovery,
as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! Drive slowly and smoothly when towing.
Excessive tractive power could otherwise
damage the vehicles.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! On vehicles with KEYLESS-GO, use the
SmartKey instead of the Start/Stop
button. Turn the SmartKey to position 2 in
the ignition lock and shift the automatic
transmission to N. Then, turn the SmartKey
back to 0 and leave it in the ignition lock.
! Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised. This could
otherwise damage the transmission.
The automatic transmission must be in
position N while the vehicle is being towed.
The battery must be connected and charged.
Otherwise:
R you will not be able to turn the SmartKey to
position 2 in the ignition lock.
R you will not be able to shift the automatic
transmission to position N.
Vehicles with automatic transmission:
manually release the selector lever lock in
position P(Y page 139).
i Switch the automatic lock ( Y page 173)
off before towing. Otherwise, you could
lock yourself out of the vehicle when
pushing or towing the vehicle.
Installing/removing the towing eye
Installing the towing eye
Vehicles with a trailer tow hitch: if possible,
fasten the towing mechanism to the trailer
tow hitch ( Y page 156).
XRemove the towing eye from the vehicle
tool kit ( Y page 245).GWarning
The exhaust tail pipe may be hot. You could
burn yourself if you touch the tail pipe. Be
particularly careful when removing the rear
cover.
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XRelease the parking brake.XSwitch on the hazard warning flashers
( Y page 105).
i
When towing with the hazard warning
flashers switched on, use the combination
switch as usual to signal in which direction
you are changing. In this case, only the
indicator lamps for the direction of travel
flash. When you reset the combination
switch, the hazard warning flashers start
flashing again.
Transporting the vehicle
The towing eyes or trailer tow hitch can be
used to pull the vehicle onto a trailer or
transporter if you wish to transport it.
XTurn the SmartKey to position 2 in the
ignition lock.XShift the selector lever to N.
As soon as the vehicle has been loaded:
XPrevent the vehicle from rolling away by
applying the parking brake.XMove the selector lever to P.XTurn the SmartKey to position 0 in the
ignition lock and remove the SmartKey.XSecure the vehicle.
! Only lash the vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components.
Otherwise, the vehicle could be damaged.
Notes on 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised,
as doing so will damage the transmission.
If the vehicle's transmission, front, or rear
axle is damaged, have the vehicle transported
on a truck or trailer.
In the event of damage to the electrical
system
If the battery is defective, the automatic
transmission will be locked in position P. To
shift the automatic transmission to position
N , you must provide power to the vehicle's
electrical system in the same way as when
jump-starting ( Y page 256).
Have the vehicle transported on a transporter
or trailer.
Recovering a vehicle that has become
stuck
! Pull away smoothly, slowly, and in a
straight line when pulling out a vehicle that
has become stuck. Excessive tractive
power could damage the vehicles.
If the drive wheels have become stuck in
loose or muddy ground, pull the vehicle out
with extreme caution, particularly if it is
laden.
Never attempt to recover a stuck vehicle with
a trailer attached.
Pull out the vehicle backwards, if possible
using the tracks it made when it became
stuck.
Fuses
Important safety notes
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
will fail.
GWarning
Only use fuses approved by Mercedes-Benz
with the specified amperage for the system in
question and do not attempt to repair or
bridge a blown fuse. Using other than
approved fuses or using repaired or bridged
fuses may cause an overload leading to a fire,
and/or cause damage to electrical
components and/or systems. Have the cause
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