Page 90 of 506

89 Safety and Security
Anti-theft systems
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating
With the SmartKey: Removing the
SmartKey from the starter switch acti-
vates the immobilizer.
With KEYLESS-GO*: Turning off the en-
gine by means of the start/stop button
on the gear selector lever activates the
immobilizer.
Deactivating
With the SmartKey: Inserting the
SmartKey in the starter switch deacti-
vates the immobilizer.
With KEYLESS-GO*: Starting the en-
gine by means of the start/stop button
on the gear selector lever deactivates
the immobilizer.
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
a door
the trunk
the hood.
The alarm system will also be triggered
when
someone attempts to raise the vehicle
(page 91)
opening the vehicle with the
mechanical key.
iIn case the engine cannot be started
(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).
iThe alarm will stay on, even if the
activating element (a door, for
example) is immediately closed.
Page 91 of 506

90 Safety and SecurityAnti-theft systemsArming the alarm system
The indicator lamp is in the switch for the
tow-away alarm in the center console.
1Indicator lamp
Lock the vehicle with the SmartKey or
KEYLESS-GO*.
The turn signal lamps flash three times
to indicate that the alarm system is
activated. Indicator lamp1 begins to
flash after approximately 30 seconds
after arming the alarm system.Disarming the alarm system
Unlock the vehicle with the SmartKey
or KEYLESS-GO*.
The turn signal lamps flash once to
indicate that the alarm system is disarmed.
iIf the alarm stays on for more than
30 seconds, a call to the Response
Center is initiated automatically by the
Tele Aid system (
page 277) provided
Tele Aid service was subscribed to and
properly activated, and that necessary
cellular service and GPS coverage are
available.
iIf the turn signal lamps do not flash
three times, one of the following
elements may not be properly closed:
a door
the trunk lid
the hood
Close the respective element and lock
the vehicle again.
iThe alarm system will rearm automati-
cally after approximately 40 seconds if
no door or the trunk lid was opened.
Page 92 of 506

91 Safety and Security
Anti-theft systems
Canceling the alarm
To cancel the alarm:
With the SmartKey
Press the Œ or ‹ button on the
SmartKey.
or
Insert the SmartKey in the starter
switch.
With KEYLESS-GO*
Pull the outside door handle.
or
Press the KEYLESS-GO start/stop
button.
Tow-away alarm
Once the tow-away alarm is armed, a visual
and audible alarm will be triggered when
someone attempts to raise the vehicle.Arming tow-away alarm
Lock the vehicle with the SmartKey or
KEYLESS-GO*.
The tow-away alarm is automatically
armed after about 30 seconds.
iThe tow-away protection alarm is
triggered, for example, if the vehicle is
lifted on one side.
If the alarm stays on for more than
30 seconds, a call to the Response
Center is initiated automatically by the
Tele Aid system (
page 277) provided
Tele Aid service was subscribed to and
properly activated, and that necessary
cellular service and GPS coverage are
available.
iWhen you unlock the vehicle, the
tow-away protection disarms
automatically. The tow-away alarm
remains disarmed until you lock the
vehicle again.
Page 93 of 506
92 Safety and SecurityAnti-theft systemsDisarming tow-away alarm
To prevent triggering the tow-away alarm,
switch off the tow-away alarm feature
before towing the vehicle, or when parking
on a surface subject to movement, such as
a ferry or auto train.
The switch is located on the center
console.
1Tow-away alarm off switch
2Indicator lamp
Switch off the ignition and remove the
SmartKey.
Press switch1.
Indicator lamp2 in switch1 comes
on briefly.
Exit and lock the vehicle with the
SmartKey or (vehicles with
KEYLESS-GO*) the lock button at each
door handle.
The tow-away alarm remains disarmed
until you lock the vehicle again.Canceling the alarm
To cancel the alarm:
With the SmartKey
Press the Œ or ‹ button on the
SmartKey.
or
Insert the SmartKey in the starter
switch.
With KEYLESS-GO*
Pull the outside door handle.
or
Press the KEYLESS-GO start/stop
button.
iYou cannot disarm the tow-away alarm
while the ignition is switched on.
Page 97 of 506

96 Controls in detailLocking and unlockingFactory setting
Global unlocking
Press buttonŒ.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system is
disarmed.
The vehicle will lock again automatically
and rearm the anti-theft alarm system
within approximately 40 seconds of
unlocking if:
neither door nor trunk is opened
the SmartKey is not inserted in the
starter switch
the central locking switch is not
activatedGlobal locking
Press button‹.
With the hood, trunk and both doors
closed, all turn signal lamps flash three
times. The locking knobs in the doors
move down. The anti-theft alarm sys-
tem is armed.
Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey so that
pressingŒ only unlocks the driver’s
door and the fuel filler flap.
Press and hold buttonsŒ and‹
simultaneously for about five seconds
until battery check lamp5 flashes
twice.
The SmartKey will then function as follows:Unlocking driver’s door and fuel filler
flap
Press buttonŒ once.
All turn signal lamps flash once. The
locking knob in the driver’s door moves
up. The anti-theft alarm system is
disarmed.
Global unlocking
Press buttonŒ twice.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system is
disarmed.
Page 98 of 506

97 Controls in detail
Locking and unlocking
Global locking
Press button‹.
With the hood, trunk and both doors
closed, all turn signal lamps flash three
times. The locking knobs in the doors
move down. The anti-theft alarm sys-
tem is armed.
Restoring to factory setting
Press and hold buttonsŒ and‹
simultaneously for about six seconds
until battery check lamp5 flashes
twice.Checking the batteries
Press button‹ orŒ.
Battery check lamp5 comes on
briefly to indicate that the SmartKey
batteries are in order.
!If you can no longer lock or unlock the
vehicle with the SmartKey, then the
batteries in the SmartKey are dis-
charged, the SmartKey is malfunction-
ing or the vehicle battery is drained.
Check the batteries in the
SmartKey (
page 97) and replace
them if necessary (
page 412).
Use the mechanical key to unlock
the driver’s door (
page 397) and
the trunk (
page 398).
Have the vehicle battery and the
battery connections checked
(page 427).
Use the mechanical key to lock the
driver’s door (
page 398).
If the SmartKey is malfunctioning,
contact an authorized Mercedes-Benz
Center.
iIf battery check lamp5 does not
come on briefly during check, then the
SmartKey batteries are discharged.
Replace the batteries (
page 412).
You can obtain the required batteries
at any authorized Mercedes-Benz
Center.
iIf the batteries are checked within
signal range of the vehicle, pressing
the‹ orŒ button will lock or
unlock the vehicle accordingly.
Page 102 of 506

101 Controls in detail
Locking and unlocking
according to the position of the Smart-
Key in the starter switch, even stopping
the engine.
If the SmartKey with KEYLESS-GO is
positioned farther away from the vehi-
cle, the system may no longer recog-
nize the SmartKey with KEYLESS-GO.
The vehicle then cannot be locked or
the engine started via the KEYLESS-GO
system.
If the SmartKey with KEYLESS-GO is re-
moved from the vehicle while the igni-
tion is switched on (e.g. if passenger
exits the vehicle with the SmartKey
with KEYLESS-GO), the message
Key
not recognized!
will appear in the
multifunction display while driving off.
Find the SmartKey with KEYLESS-GO or
change its present location immediate-
ly (e.g. place it on the front passenger
seat or insert it in shirt pocket).
Remember that the engine can be
started by anyone with a SmartKey
with KEYLESS-GO that is left inside the
vehicle. If you leave the SmartKey with
KEYLESS-GO behind when exiting and
locking the vehicle, the message
Key
recognized in vehicle!
will appear in
the multifunction display.
Factory settingGlobal unlocking
Pull the door handle.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system is
disarmed.
The vehicle will lock again automatically
within approximately 40 seconds of un-
locking if neither door nor trunk is opened.
Warning!
G
When leaving the vehicle, always take the
SmartKey with KEYLESS-GO* with you, and
lock the vehicle. Do not leave children unat-
tended in the vehicle, or with access to an
unlocked vehicle. It is possible for children
to open a locked door from the inside, which
could result in an accident and/or serious
personal injury.
iIf the vehicle has been parked for a
longer period of time, you must pull the
door handle in order to activate the
KEYLESS-GO function.
Page 103 of 506

102 Controls in detailLocking and unlockingGlobal locking
Press lock button at door handle
(page 58) or trunk lid (
page 104).
With the hood, trunk and both doors
closed, all turn signal lamps flash three
times. The locking knobs in the doors
move down. The anti-theft alarm sys-
tem is armed.Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey with
KEYLESS-GO so when you, pull the driver’s
door handle only the driver’s door and the
fuel filler flap unlocks.
Press and hold buttonsŒ and‹
simultaneously for about five seconds
until battery check lamp5 flashes
twice.
The SmartKey with KEYLESS-GO will then
function as follows:
Unlocking driver’s door and fuel filler
flap
Pull the driver’s door handle.
All turn signal lamps flash once. The
locking knob in the driver’s door moves
up. The anti-theft alarm system is
disarmed.Global unlocking
Pull the door handle on the passenger
side.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system is
disarmed.
Global locking
Press lock button at door handle.
With the hood, trunk and both doors
closed, all turn signal lamps flash three
times. The locking knobs in the doors
move down. The anti-theft alarm sys-
tem is armed.
iThe vehicle could inadvertently be
unlocked if the SmartKey with
KEYLESS-GO is within 3 ft (1 m) of the
vehicle and:
the door handle is splashed with
water, or
you attempt to clean the door
handle.
iYou can also lock the vehicle using the
lock button at trunk lid (
page 104).