Page 99 of 521

98 Safety and SecurityDriving safety systems
The electrohydraulic brake servo assis-
tance switches off automatically
approximately 2 minutes after you
turned the SmartKey in the starter
switch to position0 or removed the
SmartKey
approximately 2 minutes after you
pressed the KEYLESS-GO* start/stop
button to turn off the engine or power
supply and opened the driver’s door
(with driver’s door open, the starter
switch is set to position 0, same as
SmartKey removed from starter
switch)
approximately 20 seconds after you
locked the vehicle from outside
iIf the electrohydraulic brake system is
activated as the brake pedal is first de-
pressed, you may feel a reduced pedal
resistance and longer pedal travel than
normal. When releasing the pedal, you
may also feel the brake pedal pulsate
and you may hear a sound which is
caused by the activation of the electro-
hydraulic brake system pump. This is
normal and not an indication of a mal-
function. Pedal travel returns to normal
when you release the brake pedal and
the sound soon ceases.
If you experience the above while driv-
ing and the red brake warning lamp
(page 374) illuminates and/or warn-
ing messages appear in the instrument
cluster (
page 383), the brake system
is malfunctioning. Follow the instruc-
tions of the warning message(s) and
have the brake system checked imme-
diately.
Warning!
G
Have brake pad replacement and other work
on the electrohydraulic brake system car-
ried out by qualified technicians only. Con-
tact an authorized Mercedes-Benz Center
for further information. The electrohydraulic
brake system must be deactivated prior to
working on the system. High pressure is in-
termittently built up in the system as part of
its automatic self-test. In addition, the sys-
tem is automatically activated when the ve-
hicle is unlocked by SmartKey, when the
driver or passenger door is opened, when
the starter switch is turned to position
1,
when the brake pedal is depressed or when
the parking brake is released. Failure to de-
activate the system prior to maintenance
will cause brake pistons to extend and brake
fluid to leak, which may result in injuries
(contusions and acid burns). Extended
brake pistons may also cause injury.
Page 103 of 521

102 Safety and SecurityAnti-theft systemsArming the alarm system
The indicator lamp located in the central
locking switch 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
armed. The indicator lamp1 begins to
flash after approximately 30 seconds
after arming the alarm system.Disarming the alarm system
Unlock your vehicle with the SmartKey
or KEYLESS-GO*.
The turn signal lamps flash once to
indicate that the alarm system is
disarmed.
Canceling the alarm
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press button Œ or ‹ on the
SmartKey.
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 282) 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 ele-
ments may not be properly closed:
a door
the tailgate
the hood
Close the respective element and lock
the vehicle again.
iThe alarm system will rearm automati-
cally after approximately 40 seconds if
neither a door nor the tailgate was
opened.
Page 104 of 521
103 Safety and Security
Anti-theft systems
With KEYLESS-GO*
Pull an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
or
Press the KEYLESS-GO* start/stop
button (
page 37).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
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 trig-
gered, for example, if the vehicle is lift-
ed 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 282), provid-
ed that the Tele Aid service was sub-
scribed to and properly activated, and
that necessary cellular service and GPS
coverage are available.
Page 105 of 521

104 Safety and SecurityAnti-theft systemsDisarming 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 button is located on the overhead con-
trol panel.
1Tow-away alarm off button
Switch off the ignition and remove the
SmartKey from the starter switch.
Press button1.
The indicator lamp in the button1
comes on briefly.
Exit and lock the vehicle with the
SmartKey or (vehicles with
KEYLESS-GO*) the lock button at each
door handle.Canceling tow-away alarm
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press button Œ or ‹ on the
SmartKey.
With KEYLESS-GO*
Pull an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
or
Press the KEYLESS-GO* start/stop
button (
page 38).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iYou cannot disarm the tow-away alarm
when the ignition is switched on.
iWhen you unlock the vehicle, the
tow-away protection disarms automati-
cally.
The tow-away alarm remains disarmed
until you lock the vehicle again.
Page 107 of 521

106 Controls in detailIn the “Controls in detail” section you will
find detailed information on how to oper-
ate the equipment installed on your vehi-
cle. 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
given at the beginning of each segment.Locking and unlocking
For more information on locking and un-
locking, see “Getting started” (
page 34)
and (
page 59).
SmartKey
Your vehicle comes supplied with two
SmartKeys, each with remote control and
a removable mechanical key. The locking
tabs for the mechanical key portion of the
two SmartKeys are a different color to help
distinguish each key unit.
The SmartKey provides an extended oper-
ating range. To prevent theft, however, it is
advisable to only unlock the vehicle when
you are in close proximity to it.
The SmartKey centrally locks and unlocks
the doors
the tailgate
the fuel filler flap
SmartKey with remote control1‹ Lock button
2Š Unlock button* for the tailgate
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 90)
Page 108 of 521

107 Controls in detail
Locking and unlocking
Warning!
G
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it
with you and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. It is possible
for children to open a looked door from the
inside, which could result in an accident
and/or serious personal injury.!To prevent possible malfunction, avoid
exposing the SmartKey to high levels of
electromagnetic radiation.
iUSA 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 harmful
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.
iCanada 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 of the device.
Any unauthorized modification to this
device could void the user’s authority
to operate the equipment.iThe electrohydraulic brake system is
activated (
page 96).
iYou can also open and close the power
windows and tilt/sliding sunroof* us-
ing the SmartKey (
page 234).
Page 109 of 521

108 Controls in detailLocking and unlockingFactory settingGlobal unlocking
Press buttonŒ.
All turn signal lamps flash once.
An acoustic signal sounds once
(if equipped and feature activated).
The locking knobs in the doors
move up.
The anti-theft alarm system is dis-
armed.
The vehicle will lock again automatically
and reactivate the anti-theft alarm system
within approximately 40 seconds of un-
locking if:
neither a door nor the tailgate is
opened
the SmartKey is not inserted in the
starter switch
the central locking switch is not acti-
vatedGlobal locking
Press button‹.
All turn signal lamps flash three
times.
An acoustic signal sounds three
times (if equipped and feature acti-
vated).
The locking knobs in the doors
move down.
The anti-theft alarm system is
armed.
iYour vehicle may be equipped with an
acoustic lock and unlock confirmation
signal feature. If your vehicle is
equipped with this feature and the fea-
ture is activated, an acoustic signal will
sound when the vehicle is locked or un-
locked using the SmartKey.
To determine whether or not your vehi-
cle is equipped with this feature, con-
tact an authorized Mercedes-Benz
Center. If equipped and you wish to ac-
tivate or deactivate the feature, or ad-
just its signal volume, also contact an
authorized Mercedes-Benz Center.
Page 110 of 521

109 Controls in detail
Locking and unlocking
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 5 seconds un-
til battery check lamp5 (
page 106)
flashes twice.
The SmartKey will then function as fol-
lows:
Unlocking driver’s door and fuel filler
flap
Press buttonŒ once.
All turn signal lamps flash once.
An acoustic signal sounds once (if
equipped and feature activated).
For more information, see “Factory
setting” (
page 108).
The locking knob in the driver’s
door moves up.
The anti-theft alarm system is dis-
armed.
Global unlocking
Press buttonŒ twice.
All turn signal lamps flash once.
An acoustic signal sounds once
(if equipped and feature activated).
The locking knobs in the doors
move up.
The anti-theft alarm system is dis-
armed.
Global locking
Press button‹.
All turn signal lamps flash three
times.
An acoustic signal sounds three
times (if equipped and feature acti-
vated).
The locking knobs in the doors
move down.
The anti-theft alarm system is
armed.
Restoring to factory setting
Press and hold buttonsŒ and‹
simultaneously for about 6 seconds un-
til battery check lamp5 (
page 106)
flashes twice.