Page 105 of 521

104 Controls in detail
Locking and unlocking
SmartKey with KEYLESS-GO
1‹Lock button
2Š Opening button for trunk
(
page 108)
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 89)Opening a door causes its windows to
open slightly. It will fully close when the
door is shut.
!To prevent possible malfunction, avoid ex-
posing the SmartKey with KEYLESS-GO to high
levels of electromagnetic radiation.
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. A child’s unsupervised ac-
cess to a vehicle could result in an accident
and/or serious personal injury.
!A side window will not work if it is blocked
with ice or if the battery needs charging. If you
cannot shut a door, do not force it or you could
damage the door or the side window. Fix whatev-
er is affecting the window before trying to shut
the door.
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 interfer-
ence, 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.
Page 106 of 521

105 Controls in detail
Locking and unlocking
Important notes on using KEYLESS-GO*
You can also use the SmartKey with
KEYLESS-GO like a normal SmartKey
(
page 100).
You can combine KEYLESS-GO func-
tions with normal SmartKey functions
(e.g. unlocking with KEYLESS-GO and
locking with the‹button).
Always carry the SmartKey with
KEYLESS-GO with you.
Never store the SmartKey with
KEYLESS-GO together with:
Electronic items such as a cellular
phone or another SmartKey with
KEYLESS-GO.
Metallic objects such as coins or
metal foil.
Doing so could impair the function of
the KEYLESS-GO system.
To lock or unlock the vehicle, the
SmartKey with KEYLESS-GO must be
located outside the vehicle within ap-
proximately 3 ft (1 m) of the door to be
opened or the trunk lid.
In order to start the engine with the
SmartKey with KEYLESS-GO:
The SmartKey with KEYLESS-GO
must be located in the vehicle.
All doors must be closed.
The brake pedal must be firmly de-
pressed. Do not depress the accel-
erator.
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 (e.g. if passen-
ger exits the vehicle with the SmartKey
with KEYLESS-GO).
iYou can also open and close the windows
(
page 250) and the tilt/sliding sunroof*
(
page 257) or the soft top (page 263) using
the SmartKey with KEYLESS-GO.
!If you can no longer lock or unlock the vehi-
cle with the SmartKey with KEYLESS-GO, then
the batteries in the SmartKey with KEYLESS-GO
are discharged, the SmartKey with KEYLESS-GO
is malfunctioning or the vehicle battery is
drained.
Check the batteries in the SmartKey with
KEYLESS-GO (
page 108) and replace
them if necessary (
page 441).
Use the mechanical key to unlock the driv-
er’s door (
page 427) and the trunk
(
page 428).
Use the mechanical key to lock the driver’s
door (
page 428) and the trunk
(
page 118).
Have the vehicle battery and the battery con-
nections checked (
page 464).
If the SmartKey with KEYLESS-GO is malfunc-
tioning, contact an authorized Mercedes-Benz
Center.
Page 107 of 521

106 Controls in detail
Locking and unlocking
with the starter switch position1,
the message:
Key Not Detected
appears in the multifunction display
with the engine running, the
message:
Key Not Detected
appears 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).
If you have started the engine with the
KEYLESS-GO start/stop button
(
page 39), you can turn it off again
with:
the KEYLESS-GO start/stop button
the SmartKey inserted in the starter
switch, when the gear selector le-
ver is in positionP
Remember that the engine can be
started by anyone with a SmartKey
with KEYLESS-GO that is left inside the
vehicle.
Possibility 1:
(One SmartKey with KEYLESS-GO in
the vehicle, one SmartKey with
KEYLESS-GO outside the vehicle):
If you leave the SmartKey with
KEYLESS-GO behind when exiting and
locking the vehicle, no message ap-
pears in the multifunction display.
Possibility 2:
(One SmartKey with KEYLESS-GO in
the vehicle, no SmartKey with
KEYLESS-GO outside the vehicle):
When exiting and trying to lock the ve-
hicle, the message
Key Detected In Vehicle
will appear in the multifunction display.
The vehicle will not be locked.Factory setting
Global unlocking
Pull an outside door handle (SmartKey
with KEYLESS-GO must be near this
door).
All turn signal lamps flash once.
An acoustic signal sounds once.
The locking knobs in the doors
move up.
The anti-theft alarm system is dis-
armed.
iWhen unlocking or locking the vehicle with
the SmartKey with KEYLESS-GO an acoustic sig-
nal sounds. The acoustic signal is activated at
the factory. If you wish to deactivate the feature,
or adjust its signal volume, contact an authorized
Mercedes-Benz Center.
Page 108 of 521

107 Controls in detail
Locking and unlocking
The vehicle will lock again automatically
and rearm the anti-theft alarm system
within approximately 40 seconds of un-
locking if:
neither door nor trunk is opened.
the central locking switch is not
activated.
Global locking
Press the lock button on an outside
door handle (
page 62).
With the trunk and both doors closed:
All turn signal lamps flash three
times.
An acoustic signal sounds three
times.
The locking knobs in the doors
move down.
The anti-theft alarm system 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 5 seconds un-
til battery check lamp5 (
page 104)
flashes twice.
The SmartKey with KEYLESS-GO will
then function as follows:Unlocking driver’s door and fuel filler
flap
Pull the driver’s outside door handle.
All turn signal lamps flash once.
An acoustic signal sounds once.
The locking knob in the driver’s
door move up.
The anti-theft alarm system is dis-
armed.
Global unlocking
Pull the outside door handle on the pas-
senger side.
All turn signal lamps flash once.
An acoustic signal sounds once.
The locking knobs in the doors
move up.
The anti-theft alarm system is dis-
armed.
iThe vehicle could inadvertently be unlocked
if the SmartKey with KEYLESS-GO is
within 3 ft (1 m) of the vehicle and:
an outside door handle is splashed with wa-
ter, or
you attempt to clean an outside door handle.
Page 109 of 521

108 Controls in detail
Locking and unlocking
Global locking
Press the lock button on an outside
door handle.
With the trunk and both doors closed:
All turn signal lamps flash three
times.
An acoustic signal sounds three
times.
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 5 seconds un-
til Battery check lamp5 (
page 104)
flashes twice.Unlocking and opening the trunk
You can unlock and open the trunk sepa-
rately.
A minimum height clearance of 5.71 ft
(1.74 m) CLK coupe or 5.41 ft (1.65 m)
CLK cabriolet is required to open the
trunk lid.
Press and hold button Š until trunk
unlocks and begins to open.
The trunk can also be opened from its in-
side in an emergency, see “Trunk emer-
gency release” (
page 117).Checking the batteries in the SmartKey
or SmartKey with KEYLESS-GO*
Press button‹orŒ.
Battery check lamp (
page 100) or
(
page 104) comes on briefly to indi-
cate that the SmartKey or SmartKey
with KEYLESS-GO batteries are in
order.
iVehicles with trunk opening/closing sys-
tem*, you can also lock the vehicle using the
KEYLESS-GO locking/closing switch
(
page 116) on the trunk lid.
!The trunk lid swings open upwards automat-
ically. Always make sure there is sufficient over-
head clearance.
Vehicles with trunk opening/closing system*: To
stop the opening procedure, press button Š.
The trunk lid stops moving.
iIf the trunk does not open, it is still locked
separately (
page 118).
!If battery check lamp does not come on
briefly during check, the SmartKey or SmartKey
with KEYLESS-GO batteries are discharged.
Replace the batteries (
page 441).
You can obtain the required batteries at any au-
thorized 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 110 of 521

109 Controls in detail
Locking and unlocking
Loss of the SmartKey or SmartKey with
KEYLESS-GO*
If you lose your SmartKey, SmartKey with
KEYLESS-GO, or mechanical key, you
should do the following:
Have the SmartKey or SmartKey with
KEYLESS-GO deactivated at an autho-
rized Mercedes-Benz Center.
Report the loss of the SmartKey,
SmartKey with KEYLESS-GO, or the
mechanical key immediately to your
car insurance company.
Have the mechanical lock replaced if
necessary.
Any authorized Mercedes-Benz Center will
be glad to supply you with a replacement.
Opening the doors from the inside
You can open a locked door from the in-
side. Open doors only when conditions are
safe to do so.
Opening a door causes its windows to
open slightly. It will fully close when the
door is shut.
1Locking knob
2Inside door handle
!A side window will not work if it is blocked
with ice or if the battery needs charging. If you
cannot shut a door, do not force it or you could
damage the door or the side window. Fix whatev-
er is affecting the window before trying to shut
the door.
iIf the vehicle has been centrally locked with
the SmartKey or KEYLESS-GO*, opening a door
from the inside will trigger the anti-theft alarm
system.
To cancel the alarm, do one of the following:
With the SmartKey
Insert the SmartKey in the starter switch.
Press button‹orŒ on the
SmartKey.
With KEYLESS-GO*
Press the KEYLESS-GO* start/stop button
(
page 39).
Page 111 of 521

110 Controls in detail
Locking and unlocking
Pull on door handle2.
If door was locked, locking knob1 will
move up.
Opening the trunk
You can open the trunk if the vehicle is sta-
tionary.
A minimum height clearance of 5.71 ft
(1.74 m) CLK coupe or 5.41 ft (1.65 m)
CLK cabriolet is required to open the
trunk lid.Opening the trunk from the outside
1Handle
Press and hold button Š on the
SmartKey or SmartKey with
KEYLESS-GO* until trunk unlocks and
begins to open.
or
Pull on handle1.
In vehicles without KEYLESS-GO*:
The vehicle must be unlocked.
The SmartKey with KEYLESS-GO* must be
inside the vehicle.
Pull an outside door handle.
The SmartKey with KEYLESS-GO* must be
within 3 ft (1 m) of the vehicle.
iIf you hear a warning signal you have
forgotten to switch off the low beam headlamps
or the parking lamps before opening the driver’s
door.
In addition the message
Switch Off Lights
appears in the multifunction display.
Switch off the low beam headlamps or the park-
ing lamps.
If the message
Switch Off Lights or Re-
move Key
appears in the multifunction display
remove the SmartKey from the starter switch or
switch off the automatic headlamp mode.
!Failure to switch off the exterior lamps when
leaving the vehicle may result in a discharged
battery.
Warning!G
Make sure the trunk is closed when the en-
gine is running and while driving. Among
other dangers, such as blocked visibility, ex-
haust fumes may enter the vehicle interior.
These fumes are damaging to your health.
!The trunk lid swings open upwards automat-
ically. Always make sure there is sufficient over-
head clearance.
iIf the trunk does not open, it is still locked
separately (
page 118).
Page 112 of 521

111 Controls in detail
Locking and unlocking
Opening the trunk from the inside
Vehicles without trunk opening/closing
system*
1Remote trunk opening switch
Vehicles with trunk opening/closing
system*
1Remote trunk opening switch*
2Remote trunk closing switch*
Press remote trunk opening switch1
until the trunk begins to open.
The trunk opens. The indicator lamp
comes on and remains lit until the
trunk is closed.
!Vehicles with trunk opening/closing sys-
tem*: To stop the opening procedure, press but-
ton Š on the SmartKey or SmartKey with
KEYLESS-GO*.
iThe trunk can also be opened from its inside
in an emergency, see “Trunk emergency re-
lease” (
page 117).
iIf the trunk does not open, it is still locked
separately (
page 118).
!Vehicles with trunk opening/closing sys-
tem*: To stop the opening procedure, press
switch1 or 2.
iThe trunk can also be opened using
buttonŠ on the SmartKey or SmartKey with
KEYLESS-GO* or from its inside in an emergen-
cy, see “Trunk emergency release”
(
page 117).