Page 97 of 489

96 Safety and Security
Driving safety systems
The electro-hydraulic brake system
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 electro-hydraulic brake system is acti-
vated as the brake pedal is first depressed, 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
malfunction. Pedal travel returns to normal when
you release the brake pedal and the sound soon
ceases.
If you experience the above while driving and the
red brake warning lamp (
page 345) illumi-
nates and/or warning messages appear in the
multifunction display (
page 377), the brake
system is malfunctioning. Follow the instructions
of the warning message(s) and have the brake
system checked immediately.
Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system
carried out by qualified technicians only.
Contact an authorized Mercedes-Benz
Center for further information.
The electro-hydraulic brake system must be
deactivated prior to working on the system.
High pressure is intermittently built up in the
system as part of its automatic self-test.
In addition, the system is automatically acti-
vated when the vehicle is unlocked by re-
mote control, when the driver or passenger
door is opened, when the SmartKey in the
starter switch is turned to position1 or the
KEYLESS-GO* start/stop button is pressed
once, when the brake pedal is depressed or
when the parking brake is released. Failure
to deactivate the system prior to mainte-
nance will cause brake pistons to extend
and brake fluid to leak, which may result in
injuries (contusions and acid burns). Extend-
ed brake pistons may also cause injury.
Page 99 of 489

98 Safety and Security
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
When leaving the vehicle, always take the
SmartKey or SmartKey with KEYLESS-GO*
with you and lock the vehicle. The engine
can be started by anyone with a valid
SmartKey or SmartKey with KEYLESS-GO*
that is left inside the vehicle.
Activating
With the SmartKey
Remove the SmartKey from the starter
switch.
With KEYLESS-GO*
Press the start/stop button on the gear
selector lever once.
The engine is turned off.
Open the driver’s door.Deactivating
With the SmartKey
Turn the SmartKey in the starter switch
to position2 (
page 40).
With KEYLESS-GO*
Switch on the ignition (page 41).
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 lid
the hood
a storage compartment in the rear
the glove box
the storage compartment under the
armrest
The alarm will stay on, even if the activat-
ing element (a door, for example) is imme-
diately closed.
iStarting the engine will also deactivate the
immobilizer.
In 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).
Page 100 of 489

99 Safety and Security
Anti-theft systems
The alarm system will also be triggered
when
someone attempts to raise the vehicle
unlocking and opening the driver’s
door, the trunk, or the glove box with
the mechanical key
someone opens a door from the inside
someone opens the trunk lid with the
emergency release buttonArming the alarm system
The alarm system indicator lamp is located
in the locking switch in the upper part of
the center console.
1Alarm system indicator lamp
Lock the vehicle with the SmartKey or
KEYLESS-GO*.
The turn signal lamps flash three times
and an acoustic warning sounds three
times to indicate that the alarm system
is armed.
Alarm system indicator lamp 1 starts
flashing.Disarming the alarm system
Unlock the vehicle with the SmartKey
or KEYLESS-GO*.
The turn signal lamps flash once and an
acoustic warning sounds once to
indicate that the alarm system is
disarmed.
Alarm system indicator lamp 1 goes
out.
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is ini-
tiated automatically by the Tele Aid system
(
page 252) provided Tele Aid service was sub-
scribed to and properly activated, and that nec-
essary cellular service and GPS coverage are
available.
iIf the turn signal lamps do not flash three
times and no acoustic warning sounds three
times, a door or the trunk lid may not be properly
closed.
Close the respective element and lock the
vehicle again.
iThe alarm system will rearm automatically
again after approximately 40 seconds if no door
was opened.
Page 101 of 489

100 Safety and Security
Anti-theft systems
Canceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press theŒor‹button on the
SmartKey.
With KEYLESS-GO*
Grasp 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 but-
ton (
page 41).
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 your vehicle with the SmartKey or
KEYLESS-GO*
The tow-away alarm is automatically
armed after about 30 seconds.
Disarming tow-away alarm
To prevent triggering the tow-away alarm,
disable 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 button is located on the center
console between the driver’s seat and the
passenger seat.
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 252) provided Tele Aid service was
subscribed to and properly activated, and that
necessary cellular service and GPS coverage are
available.
iWhen you unlock your vehicle, the tow-away
protection disarms automatically. The tow-away
alarm remains disarmed until you lock the
vehicle again.
Page 102 of 489
101 Safety and Security
Anti-theft systems
1Tow-away alarm off button
2Indicator lamp
Switch off the ignition and remove the
SmartKey from the starter switch.
Press button1.
The indicator lamp2 in the switch
comes on briefly.
Exit and lock your vehicle with the
SmartKey or (vehicles with
KEYLESS-GO*) with the lock button on
a door handle.
The tow-away alarm remains disarmed un-
til you lock the vehicle again.
Canceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press theŒor‹button on the
SmartKey.With KEYLESS-GO*
Grasp 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 41).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iYou cannot disarm the tow-away alarm
when the ignition is switched on.
Page 104 of 489
103 Controls in detail
Locking and unlocking
Seats
Memory function
Lighting
Instrument cluster
Control system
Automatic transmission
Good visibility
Automatic climate control
Power windows
Retractable hardtop
Driving systems
Useful features
Page 105 of 489

104 Controls in detail
In 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 giv-
en at the beginning of each segment.
For more information on locking and un-
locking, see the “Getting started” section
(
page 38).
Locking and unlocking
SmartKey
Your vehicle comes supplied with two
SmartKeys, each with remote control and
a removable mechanical key.
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 trunk lid
the glove box
the storage compartment under the
armrest
the storage compartment in the rear
the fuel filler flap
SmartKey with remote control
1‹Lock button
2Š Opening button for trunk
(
page 114)
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 88)
Page 106 of 489

105 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. A child’s
unsupervised access to a vehicle could
result in an accident and/or serious
personal injury.
!To prevent possible malfunction, avoid ex-
posing the SmartKey to high levels of electro-
magnetic 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.
iYou can also open and close the power win-
dows (
page 201) and the retractable hardtop
using the SmartKey (
page 206).
!If you cannot lock or unlock the vehicle
with the SmartKey, then the batteries in the
SmartKey are discharged, the SmartKey is mal-
functioning or the vehicle battery is drained.
Check the batteries in the SmartKey
(
page 113) and replace them if necessary
(
page 407).
Use the mechanical key to unlock the
driver’s door (
page 403) and the trunk
(
page 404).
Have the vehicle batteries and their
connections checked (
page 427).
Use the mechanical key to lock or unlock the
doors (
page 405).
If the SmartKey is malfunctioning, contact
Roadside Assistance or an authorized
Mercedes-Benz Center.