Page 79 of 360

79 Safety and Security
Anti-theft systems
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating
Removing the key from the starter switch
activates the immobilizer.
Deactivating
Inserting the key in the starter switch de-
activate the immobilizer.
Anti-theft alarm
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone:
opens a door
opens the tailgate
opens the hood
The alarm will stay on even if the activating
element (a door, for example) is immedi-
ately closed.
The alarm system will also be triggered
when
someone attempts to raise the vehicle
opening the vehicle with the mechani-
cal keyArming the alarm system
The alarm system is armed after locking
the vehicle with the SmartKey. The turn
signal lamps blink three times to indicate
that the alarm system is activated. A red
lamp in the tow-away alarm switch will
blink after approximately 10 seconds
when the alarm system is completely
armed (
page 27).
iIf the alarm stays on for more than
20 seconds, an emergency call is initi-
ated automatically by the Tele Aid sys-
tem (
page 183) provided Tele Aid
service was subscribed to and properly
activated, and that necessary cellular
service and GPS coverage are avail-
able.
Page 80 of 360

80 Safety and SecurityAnti-theft systemsDisarming the alarm system
The alarm system is disarmed when you
unlock your vehicle with the SmartKey. The
turn signal lamps blink once to indicate
that the alarm system is deactivated.Canceling the alarm
To cancel the alarm:
Insert the key in the starter switch.
or
Press the
Œ
or
‹
button on the
remote control.
The alarm is cancelled.
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.
iIf the turn signal lamps do not blink
three times, one of the following ele-
ments may not be properly closed:
a door
the tailgate
the hood
Close the respective element and lock
the vehicle again.
iThe tow-away protection alarm is trig-
gered, for example, if the vehicle is lift-
ed on one side.
If the alarm stays on for more than
20 seconds, an emergency call is initi-
ated automatically by the Tele Aid sys-
tem provided Tele Aid service was
subscribed to and properly activated,
and that necessary cellular service and
GPS coverage are available.
Page 81 of 360
81 Safety and Security
Anti-theft systems
Arming tow-away alarm
When you lock your vehicle, the tow-away
alarm is automatically armed.
When you unlock your vehicle, the
tow-away protection disarms
automatically.
Disarming tow-away alarm
To prevent triggering the tow-away alarm
feature, switch off the tow-away alarm be-
fore 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 con-
sole.
1Tow-away alarm off switch
2Indicator lamp
Turn off the ignition and remove the
key.
Press upper half1 of the switch.
Indicator lamp2 in the switch lights up
briefly.
Lock your vehicle with the key.
The tow-away alarm remains disarmed un-
til you lock your vehicle again.
iYou cannot disarm the tow-away alarm
if the ignition is turned on.
Page 84 of 360

84 Controls in detailLocking and unlockingIn the “Controls in detail” section you will
find detailed information on how to oper-
ate the equipment installed in your vehicle.
If you are already familiar with the basic
functions of your vehicle, this section will
be of particular interest to you.
To quickly familiarize yourself with the ba-
sic functions of the vehicle, refer to the
“Getting started” section of this manual.
The corresponding page numbers are giv-
en at the beginning of each segment.
Locking and unlockingKeys
Your vehicle comes supplied with two
SmartKeys with remote controls and a re-
movable mechanical key. The locking tabs
for the mechanical key portion of the two
keys are a different color to help distin-
guish each key unit.
The remote control key provides an ex-
tended operating range. To prevent theft,
however, it is advisable to only unlock the
vehicle when you are in close proximity to
it.
The key centrally locks and unlocks:
the doors
the tailgate
the fuel filler flap
SmartKey with remote controls1‹
Lock button
2Locking tab for mechanical key
3
Œ
Unlock button
4Battery check lamp
5
Â
Panic button (
page 70)
iYou can also open and close the power
windows (
page 159) and slid-
ing/pop-up roof (
page 161) using
the SmartKey.
Page 85 of 360

85 Controls in detail
Locking and unlocking
Factory setting
Global unlocking
Press button
Œ
.
All turn signal lamps blink once. The
locking knobs in the doors move up.
The vehicle will lock again automatically
within approximately 40 seconds of un-
locking if neither door nor tailgate is
opened, the SmartKey is not inserted in
the starter switch, or the central locking
switch is not activated.
Global locking
Press button
‹
.
All turn signal lamps blink three times.
The locking knobs in the doors move
down.Selective setting
If you frequently travel alone, you may wish
to reprogram the key so that
pressing
Œ
only unlocks the driver’s
door and the fuel filler flap.
Press and hold buttons
Œ
and
‹
simultaneously for about five seconds
until battery check lamp6 blinks twice.
The key will then function as follows:
Unlocking driver’s door and fuel filler
flap
Press button
Œ
once.
Global unlocking
Press button
Œ
twice.
Global locking
Press button
‹
.Restoring to factory setting
Press and hold buttons
Œ
and
‹
simultaneously for about six seconds
until the battery check lamp6 blinks
twice.
!To prevent possible malfunction, avoid
exposing the key to high levels of elec-
tromagnetic radiation.
Warning!
G
When leaving the vehicle, always remove the
key from the starter switch, and lock the ve-
hicle. Do not leave children unattended 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 re-
sult in an accident and/or serious personal
injury.
Page 86 of 360

86 Controls in detailLocking and unlocking
Checking the batteries
Press button
‹
or
Œ
.
Battery check lamp6 lights up briefly
to indicate that the key batteries are in
order.Loss of SmartKey or mechanical key
If you lose a SmartKey or mechanical key,
you should do the following:
Have the SmartKey deactivated by an
authorized Mercedes-Benz Center.
Report the loss of the SmartKey or the
mechanical key immediately to your
car insurance company.
If necessary have the mechanical lock
replaced.
Your authorized Mercedes-Benz Light
Truck Center will be glad to supply you
with a replacement.
!If you can no longer lock or unlock the
vehicle with the SmartKey, then the
batteries in the remote control are dis-
charged, the SmartKey is malfunction-
ing or the vehicle battery is drained.
Use the mechanical key to unlock
the doors (
page 272).
Check the vehicle battery
(page 295).
Check the batteries in the key and
replace them if necessary
(page 86).
Use the mechanical key to lock the
doors and the tailgate
(page 273).
If the key is malfunctioning, contact an
authorized Mercedes-Benz Light Truck
Center.
!If battery check lamp6 does not light
up briefly during check, then the key
batteries are discharged.
Replace the batteries (
page 273).
You can obtain the required batteries
at any authorized Mercedes-Benz Light
Truck Center.
Page 88 of 360

88 Controls in detailLocking and unlockingOpening the tailgate from inside
1Locking knob
2Inside door handle
Pull on door handle 2.
If door was locked, the locking knob 1
will move up.Separately locking the tailgate
1Locked
2Unlocked
Close the tailgate
Pull the mechanical key out of the
SmartKey (
page 272).
Turn the mechanical key completely to
the right to position1.
The tailgate will remain locked, even if
the vehicle is centrally unlocked.Separately unlocking the tailgate
Turn the mechanical key completely to
the left to position2.
Closing the tailgate
Warning!
G
Do not leave children unattended in the ve-
hicle. Unsupervised use of vehicle equip-
ment may cause an accident and/or serious
personal injury.
Warning!
G
To prevent possible personal injury, always
keep hands and fingers away from the tail-
gate opening when closing the tailgate. Be
especially careful when small children are
around.
Only drive with the tailgate closed as other-
wise exhaust fumes may enter the vehicle
interior.
Page 89 of 360

89 Controls in detail
Locking and unlocking
Automatic central locking
The doors and the tailgate automatically
lock when the ignition is switched on and
the wheels are turning at vehicle speeds of
approximately 9 mph (15 km/h) or more.
You can open a locked door from the in-
side. Open door only when conditions are
safe to do so.
You can deactivate the automatic locking
using the control system (
page 127).
Locking and unlocking from the inside
You can lock or unlock the vehicle from in-
side using the central locking switches.
This can be useful, for example, if you want
to unlock the passenger door from the in-
side or want to lock the vehicle before
starting to drive.
The fuel filler flap cannot be locked or un-
locked with the central locking switch.
iThe doors unlock automatically after an
accident if the force of the impact ex-
ceeds a preset threshold.
The vehicle automatically locks when
the ignition is switched on and the
wheels are turning. You could therefore
lock yourself out when the vehicle
is pushed
is on a test stand
Warning!
G
When leaving the vehicle, always remove the
key from the starter switch, and lock the ve-
hicle. Do not leave children unattended in
the vehicle, or with access to an unlocked
vehicle. Unsupervised use of vehicle equip-
ment may cause an accident and/or serious
personal injury.