
the instrument cluster does not flash. In such
situations, ESP
®
will not stabilize the vehicle.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravel
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R traction control is still activated.
R PRE-SAFE ®
is no longer available, nor is it
activated if you brake firmly and ESP ®
intervenes.
R PRE-SAFE ®
Brake is no longer available; it
is also not activated if you brake firmly and
ESP ®
intervenes.
R ABS still provides support when you brake.
R engine torque is no longer limited and the
drive wheels are able to spin. The spinning
wheels produce a cutting effect for better
traction.
Vehicles with ECO start/stop function: the
ECO start/stop function switches the engine
off automatically when the vehicle comes to
a stop. The engine starts automatically when
the driver wants to pull away again. ESP ®
remains in its previously selected status.
Example: if ESP ®
was deactivated before the
engine was switched off, ESP ®
remains
deactivated when the engine is switched on
again. EBD (electronic brake force
distribution)
i Observe the "Important safety notes"
section ( Y page 67).G
WARNING
If EBD has malfunctioned, the rear wheels can
still lock, e.g. under full braking. This
increases
the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have the brake system checked at a qualified
specialist workshop.
Observe information regarding indicator and
warning lamps ( Y page 278) as well as
display messages
(Y page 248).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking. ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
(Y page 196) and hill start assist
(Y page 156). PRE-SAFE
®
Brake
i Observe the "Important safety notes"
section ( Y page 67).
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
PRE-SAFE ®
Brake can help you to minimize
the risk of a collision with a vehicle ahead or
reduce the effects of such a collision. If PRE-
SAFE ®
Brake detects a risk of collision, you
will be warned visually and acoustically as
well as by automatic braking. PRE-SAFE ®
Brake cannot prevent a collision without your
intervention.
Above a speed of around 4 mph (7 km/h), this
function warns you if you are very quickly
approaching a vehicle in front. An
intermittent warning tone will then sound and
the · distance warning lamp will light up
in the instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.72
Driving safety systems
Safety

ATA (anti-theft alarm system)
X
To arm: lock the vehicle with the SmartKey
or KEYLESS-GO.
Indicator lamp : flashes. The alarm
system is armed after approximately
15 seconds.
X To disarm: unlock the vehicle with the
SmartKey or KEYLESS-GO.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the trunk lid/tailgate
R the hood
X To turn the alarm off with the
SmartKey:
press the % or & button
on the SmartKey.
The alarm is switched off.
or
X Insert the SmartKey into the ignition lock.
The alarm is switched off.
X To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The
SmartKey must be outside the vehicle.
The alarm is switched off.
or
X Press the Start/Stop button on the
dashboard. The SmartKey must be inside
the vehicle.
The alarm is switched off.
The alarm is not switched off, even if you
close the open door that has triggered it, for
example. i
If the alarm stays on for more than
30 seconds,
the Tele Aid system initiates a
call to the Customer Assistance center
automatically. The emergency call system
initiates the call provided that:
R you have subscribed to the mbrace/
TELEAID Service.
R the mbrace/TELEAID Service has been
activated properly.
R the required mobile phone, power supply
and GPS are available. Theft deterrent locking system
75
Safety Z

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible.
Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 25).SmartKey
Important safety notes
G
WARNING
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:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure 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.
G
WARNUNG
If a key ring is too heavy or too large, the
weight
acting on the SmartKey could cause it
to turn in the ignition lock or catch on the
steering wheel. This could cause the engine
to be switched off suddenly. You could lose
control of the vehicle and cause an accident.
Do not attach any heavy or large key rings to
the SmartKey that is inserted in the ignition.
i USA only:
This device complies with Part 15 of the
FCC Rules. 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.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
The Product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada 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.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment. 78
SmartKey
Opening/closing

The Product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
R Do not keep the SmartKey:
-with electronic devices, e.g. a mobile
phone or another SmartKey
- with
metallic objects, e.g. coins or metal
foil
- inside metallic objects, e.g. a metal case
This can affect the SmartKey's
functionality.
Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected. SmartKey functions
:
& To lock the vehicle
; F To open/close the tailgate
= % To unlock the vehicle
X To unlock centrally: press the %
button.
If you do not open the vehicle within
approximately
40 seconds of unlocking:
R the vehicle is locked again.
R the theft deterrent locking system is
armed again.
X To lock centrally: press the & button.
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid/tailgate
R the fuel filler flap 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. The audible
signal can be activated and deactivated using
the on-board computer (Y page 240).
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 239). KEYLESS-GO
General notes Bear in mind that the engine can be started
by any of the vehicle occupants if there is a
KEYLESS-GO key in the vehicle.
Locking and unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO.
To do this, you only need carry
the SmartKey with you. When you touch the
surface of the sensors on the vehicle's
outside door handles, KEYLESS-GO
establishes a radio connection between the
vehicle and the SmartKey. When the engine
is started and whilst you are driving,
KEYLESS-GO also checks whether a valid
SmartKey is in the vehicle by periodically
establishing radio contact.
You can combine the KEYLESS-GO functions
with those of a conventional key, e.g. using
KEYLESS-GO to unlock and pressing the
& button to lock.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the
corresponding door handle must not be
greater than 3 ft (1 m). SmartKey
79
Opening/closing Z

X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor
surface :.
X Convenience closing feature: touch
recessed sensor surface ; for an
extended period.
X To unlock the trunk lid/tailgate: pull the
handle on the trunk lid/tailgate.
Further information on the convenience
closing feature ( Y page 94).Changing the settings of the locking
system
You can change the settings of the locking
system.
This means that only the driver's door
and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you
frequently travel on your own.
X To change the setting: press and hold
down the % and & buttons on the
SmartKey simultaneously for
approximately
six seconds until the battery
check lamp flashes twice ( Y page 81).
i If the setting of the locking system is
changed within the signal range of the
vehicle,
pressing the & or % button:
R locks or
R unlocks the vehicle The SmartKey now functions as follows:
X
To unlock the driver's door: press the
% button once.
X To unlock centrally: press the %
button twice.
X To lock centrally: press the & button.
The KEYLESS-GO function is changed as
follows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press
and
hold down the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice ( Y page 81). 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/
tailgate, the anti-theft alarm system will be
triggered (
Y page 75).
There are several ways to turn off the alarm:
X To turn the alarm off with the
SmartKey:
press the % or & button
on the SmartKey.
or
X Insert the SmartKey into the ignition lock.
or
X To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the80
SmartKey
Opening/closing

ignition lock. The SmartKey must be in the
vehicle.
or
X Lock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key :
Release catch
; Mechanical key
X Push release catch : in the direction of
the arrow and at the same time remove
mechanical key ; from the SmartKey.SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and caustic
substances. For this reason, keep batteries
out of the reach of children.
If
a battery has been swallowed, seek medical
help immediately. G
WARNING
The SmartKey batteries contain perchlorate
material, which may require special handling and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Mercedes-Benz recommends that you have
the
batteries replaced at a qualified specialist
workshop.
Checking the battery X
Press the & or % button.
The battery is working properly if battery
check lamp : lights up briefly.
The battery is discharged if battery check
lamp : does not light up briefly.
X Change the battery ( Y page 81).
i If
the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the & or % button:
R locks or
R unlocks the vehicle
i You can get a battery in any qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 80). SmartKey
81
Opening/closing Z

Doors
Important safety notes
G
WARNING
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:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure 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. G
WARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk/cargo
compartment 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 Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked.
You
can only open the rear doors from inside
the vehicle if they are not secured by the
child-proof locks (Y page 66). X
Pull door handle ;.
If
the door is locked, locking knob : pops
up. The door is unlocked and can be
opened. Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. X
To unlock: press button :.
X To lock: press button ;.
If
all the doors are closed, the vehicle locks.
You cannot unlock the vehicle centrally from
the
inside if the vehicle has been locked with
the SmartKey or KEYLESS-GO. Doors
85
Opening/closing Z

The central locking/unlocking button does
not lock or unlock the fuel filler flap.
You can open a front door from inside the
vehicle even if it has been locked.
If the vehicle has been locked using the
locking button for the central locking, or has
been locked automatically, and a door is
opened from the inside:
R
the vehicle will be fully unlocked if it had
previously been fully unlocked
R only
the door which has been opened form
the inside is unlocked if only the driver's
door had been previously unlocked Automatic locking feature
X
To deactivate: press and hold button :
for
about five seconds until a tone sounds.
X To activate: press and hold button ; for
about five seconds until a tone sounds.
i If you press one of the two buttons and
do
not hear a tone, the relevant setting has
already been selected.
The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning.
You could therefore lock yourself out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is on a roller dynamometer.
You can also switch the automatic locking
function on and off using the on-board
computer (Y page 240). Unlocking the driver's door
(mechanical key)
If
the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
X Take the mechanical key out of the
SmartKey (Y page 80).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 1
To unlock
X Turn the mechanical key counter-clockwise
to position 1.
The door is unlocked.
X Turn the mechanical key back and remove
it.
X Insert the mechanical key into the
SmartKey.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered
(Y page 75). Locking the vehicle (mechanical key)
If
the vehicle can no longer be locked with the
SmartKey, use the mechanical key.
X Open the driver's door.
X Close the front-passenger door, the rear
doors and the trunk lid/tailgate.
X Press the locking button (Y page 85).
X Check whether the locking knobs on the
front-passenger door and the rear doors
are still visible. Press down the locking
knobs manually, if necessary
(Y page 85). 86
Doors
Opening/closing