Page 89 of 506

88 Safety and SecurityDriving safety systemsWhen you switch off the ESP
the ESP does not stabilize the vehicle
the engine output is not limited, which
allows the drive wheels to spin and
thus cut into surfaces for better grip
the traction control will still brake a
spinning wheel
the ESP continues to operate when you
are brakingThe switch is located on the center con-
sole.
1ESP switch (off/on)
Press switch1.
The ESP warning lamp v in the in-
strument cluster comes on.
The ESP is deactivated.
Switching on the ESP
Press switch1 again.
The ESP warning lamp v in the in-
strument cluster goes out.
You are now again in normal driving
mode with ESP switched on.
iWhen the ESP is switched off and one
or more drive wheels are spinning, the
ESP warning lampv in the instru-
ment cluster flashes. However, the ESP
will then not stabilize the vehicle.
Warning!
G
When the ESP warning lampv is
illuminated continuously, the ESP is
switched off.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP.!Avoid spinning of a drive wheel for an
extended period with the ESP switched
off. This may cause serious damage to
the drivetrain which is not covered by
the Mercedes-Benz Limited Warranty.
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 94 of 506
93 Controls in detail
Locking and unlocking
Seats
Memory function
Lighting
Instrument cluster
Control system
Automatic transmission
Good visibility
Climate control (CLK 320)
Automatic climate control (CLK 500/CLK 55 AMG)
Audio system
Power windows
Soft top
Driving systems
Loading
Useful features
Page 95 of 506

94 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 giv-
en at the beginning of each segment.Locking and unlocking
For more information on locking and
unlocking, see “Getting started”
(page 32) and (
page 55).
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
SmartKey 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 glove box
the trunk lid
the fuel filler flap
SmartKey with remote control1‹ Lock button
2Š Opening button for trunk lid
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 83)
Page 96 of 506

95 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 locked door from the
inside, which could result in an accident
and/or serious 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 inter-
ference received, including interfer-
ence 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 interfer-
ence, and
(2) this device must accept any inter-
ference received, including interfer-
ence 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 soft
top (
page 251) and the power win-
dows (page 242) using the
SmartKey.