
However, it does not protect the chest or
arms.
In the event of a side impact, the window cur-
tain air bag is deployed on the side on which
the impact occurs.
If the system determines that they can offer
additional protection to that provided by the
seat belt, a window curtain air bag may be
deployed in other accident situations
( Y
page 56).
Occupant Classification System
(OCS)
Introduction The Occupant Classification System (OCS)
categorizes the person in the front-passenger
seat. Depending on that result, the front-
passenger front air bag and front-passenger
knee bag are either enabled or deactivated.
The system does not disable: R
the side impact air bag R
the window curtain air bag R
the Emergency Tensioning Devices
Prerequisites
To be classified correctly, the front passenger
must sit: R
with the seat belt fastened correctly R
in an almost upright position with their
back against the seat backrest R
with their feet resting on the floor, if possi-
ble
If the front passenger does not observe these
conditions, OCS may produce a false classi-
fication, e.g. because the front passenger: R
transfers their weight by supporting them-
selves on a vehicle armrest R
sits in such a way that their weight is raised
from the seat cushion
If it is absolutely necessary to install a child
restraint system on the front-passenger seat,
be sure to observe the correct positioning of the child restraint system. Never place
objects under or behind the child restraint
system, e.g. cushions. The entire base of the
child restraint system must always rest on the
seat cushion of the front-passenger seat. The
backrest of the forward-facing child restraint
system must lie as flat as possible against the
backrest of the front-passenger seat.
The child restraint system must not touch the
roof or be subjected to a load by the head
restraint. Adjust the angle of the seat back-
rest and the head restraint position accord-
ingly.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint
system manufacturer's installation instruc-
tions.
Operation of Occupant Classification
System (OCS)
C
PASSENGER AIR BAG ON indicator lamp D
PASSENGER AIR BAG OFF indicator lamp
The indicator lamps inform you whether the
front-passenger front air bag is deactivated or
enabled. X
Press the Start/Stop button once or twice,
or turn the SmartKey to position 1 or 2 in
the ignition lock.
The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps
must light up simultaneously for approx-
imately six second s.Occu pant safety 51
Safety Z

No steering assistance is provided from
STEER CONTROL, if: R
ESP ®
is malfunctioning.R
the lighting is faulty.
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering.
Protection against theft
Immobilizer The immobilizer prevents your vehicle from
being started without the correct SmartKey. X
To activate with the SmartKey: remove
the SmartKey from the ignition lock. X
To activate with KEYLESS-GO start-
function or KEYLESS-GO: switch the igni-
tion off and open the driver's door. X
To deactivate: switch on the ignition.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Any-
one can start the engine if a valid SmartKey
has been left inside the vehicle.
i The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be star-
ted (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).
ATA (anti-theft alarm system) X
To arm: lock the vehicle with the SmartKey
or KEYLESS-GO.
Indicator lamp C flashes. The alarm sys-
tem is armed after approximately
15 seconds. X
To disarm: unlock the vehicle with the
SmartKey or KEYLESS-GO.
or X
Insert the SmartKey into the ignition lock.
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 R
the hood X
To turn the alarm off with the SmartKey:
press the 6 or 7 button on the
SmartKey.
The alarm is switched off.
or X
Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
( Y
page 147). 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 Smart-
Key must be outside the vehicle.
The alarm is switched off.
or X
Press the Start/Stop button on the dash-
board. 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 triggered it, for
example.
i If the alarm continues for more than
30 seconds, the mbrace emergency call
system automatically notifies the Cus-
tomer Assistance Center. This is done
either by text message or data connection.Protection against theft 73
Safety Z

Useful information
i This Operator's Manual describes all
models and all standard and optional equip-
ment 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 special-
ist workshops ( Y
page 25).
SmartKey
Important safety notes
G WARNING
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 PR
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.
G WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident. Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the SmartKey: 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.
Vehicles with KEYLESS-GO start function:
do not keep the SmartKey in the cargo com-
partment. Otherwise, the SmartKey may not
be detected, e.g. when starting the engine
using the Start/Stop button.
SmartKey functions
C
7 To lock the vehicle D
T To open the trunk lid

X
Insert the SmartKey into the ignition lock.
or X
To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the igni-
tion 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
X
Push release catch C in the direction of
the arrow and at the same time remove
mechanical key D from the SmartKey.
For further information about: R
unlocking the driver's door ( Y
page 85)R
unlocking the trunk ( Y
page 87)R
locking the vehicle ( Y
page 85)
Inserting the mechanical key X
Push mechanical key D completely into
the SmartKey until it engages and release
catch C is back in its basic position. SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National
guidelines must be observed during disposal.
In California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Mercedes-Benz recommends that you have
the battery replaced at a qualified specialist
workshop.
Checking the battery
X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 80).SmartKey 79
Opening and closing Z