keyless MERCEDES-BENZ CLK320 CABRIOLET 2004 A209 Owner's Guide
Page 86 of 464
86 Safety and SecurityAnti-theft systemsCanceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter 
switch.
or
Press the Œ or ‹ button on the 
SmartKey.With KEYLESS-GO*
Grasp the outside door handle.
or
Press the KEYLESS-GO start/stop 
button. 
Page 89 of 464
89 Controls in detail
Locking and unlocking
Factory setting
Global unlocking
Press buttonŒ.
All turn signal lamps flash 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 trunk 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 flash three times. 
The locking knobs in the doors move 
down.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 five seconds 
until battery check lamp5 flashes 
twice.
The SmartKey will then function as fol-
lows:
Unlocking driver’s door and fuel filler 
flap
Press buttonŒ once.
Global unlocking
Press buttonŒ twice.
Global locking
Press button‹.Restoring to factory setting
Press and hold buttonsŒ and‹ 
simultaneously for about six seconds 
until battery check lamp5 flashes 
twice.Warning!
G
When leaving the vehicle, always remove the 
SmartKey from the starter switch, 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. It is possible for children 
to open a locked door from the inside, which 
could result in an accident and/or serious 
personal injury. 
Page 91 of 464
91 Controls in detail
Locking and unlocking
The trunk lid can also be opened from its 
inside in an emergency, see “Trunk lid 
emergency release” (
page 105).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 Center 
will be glad to supply you with a replace-
ment. 
SmartKey with KEYLESS-GO*
Specially equipped vehicles come with two 
SmartKeys with KEYLESS-GO, each with 
remote control and a removable mechani-
cal key. The locking tabs for the mechani-
cal key portion of the two SmartKeys are a 
different color to help distinguish each 
SmartKey unit.
The KEYLESS-GO function is integrated 
into the SmartKey. On these vehicles, the 
validity of the SmartKey with KEYLESS-GO 
is checked every time you pull a door 
handle.
iIf the trunk lid does not open, it is still 
locked separately (if applicable) 
(page 106)
If the vehicle was previously centrally 
locked, the trunk lid will lock automati-
cally when closed (
page 100). The 
turn signals will flash three times to 
confirm locking.
!To prevent possible malfunction, avoid 
exposing the SmartKey with 
KEYLESS-GO to high levels of electro-
magnetic radiation. 
Page 92 of 464
92 Controls in detailLocking and unlockingIf the SmartKey with KEYLESS-GO* is valid, 
your vehicle unlocks
the doors
the glove box
the trunk lid
the fuel filler flap
SmartKey with KEYLESS-GO1‹ Lock button
2Š Opening button for trunk lid
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 75)For more information on using the 
SmartKey buttons, see “SmartKeys” 
(
page 88) 
Important notes on using KEYLESS-GO*
You can also use the SmartKey with 
KEYLESS-GO like a normal SmartKey 
(page 88).
You can combine KEYLESS-GO func-
tions with normal SmartKey functions 
(e.g. unlocking with KEYLESS-GO and 
locking with the remote control).
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
Warning!
G
When leaving the vehicle, always remove the 
SmartKey from the starter switch, 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. Unsupervised use of vehi-
cle equipment may cause an accident 
and/or serious personal injury.iYou can also open and close the soft 
top (
page 222) and the power win-
dows (page 213) using the 
SmartKey.
iIf the vehicle has been parked for a 
longer period of time, you must pull the 
door handle in order to activate the 
KEYLESS-GO function. 
Page 93 of 464
93 Controls in detail
Locking and unlocking
Doing so could impair the function of 
the KEYLESS-GO system.
To lock or unlock the vehicle, the 
SmartKey with KEYLESS-Go must be lo-
cated outside the vehicle within ap-
proximately 3 ft (1 m) of a door or the 
trunk.
In order to start the engine with the 
SmartKey with KEYLESS-GO:
the SmartKey with KEYLESS-GO 
must be located in the vehicle
all the doors must be closed
the brake pedal must be depressed
If you have started the engine with the 
KEYLESS-GO start/stop button, you 
can only turn it off again with this but-
ton, even if you have put the SmartKey 
in the starter switch in the meantime.
This does not apply if, after starting, the 
gear selector lever is still in positionP. 
and the SmartKey is then inserted in 
the starter switch. The SmartKey will 
then have priority over the 
KEYLESS-GO function and the vehicle’s 
electrical system will operate accord-
ing to the position of the SmartKey in 
the starter switch, even stopping the 
engine.
If the SmartKey with KEYLESS-GO is 
positioned farther away from the vehi-
cle the system may no longer recognize 
the SmartKey with KEYLESS-GO. The 
vehicle cannot be locked or the engine 
started via the KEYLESS-GO system.
If the SmartKey with KEYLESS-GO is re-
moved from the vehicle while the igni-
tion is switched on (e.g. if passenger 
exits the vehicle with the SmartKey 
with KEYLESS-GO), the message 
Key 
not recognized!
 will appear in the 
multifunction display.
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).
Remember that the engine can be 
started by anyone with a SmartKey 
with KEYLESS-GO that is left inside the 
vehicle. If you leave the SmartKey with 
KEYLESS-GO behind when exiting and 
locking the vehicle, the message 
Key 
recognized in vehicle!
 will appear in 
the multifunction display. 
Page 94 of 464
94 Controls in detailLocking and unlockingFactory setting
Global unlocking
Pull the door handle.
The vehicle will lock again automatically 
within approximately 40 seconds of un-
locking if neither door nor trunk is opened.
Global locking
Press lock button at door handle 
(page 56) or trunk lid (
page 95).Selective setting
If you frequently travel alone, you may wish 
to reprogram the SmartKey with 
KEYLESS-GO so when you, grasp the driv-
er’s door handle only the driver’s door and 
the fuel filler flap unlocks.
Press and hold buttonsŒ and‹ 
simultaneously for about five seconds 
until battery check lamp5 flashes 
twice.
The SmartKey with KEYLESS-GO will 
then function as follows:
Unlocking driver’s door and fuel filler 
flap
Grasp the driver’s door handle.
Global unlocking
Grasp the door handle on the pas-
senger side.
Global locking
Press lock button at door handle or 
trunk lid.Restoring to factory setting
Press and hold buttonsŒ and‹ 
simultaneously for about six seconds 
until battery check lamp5 flashes 
twice.
iThe vehicles could inadvertently be un-
locked if the SmartKey with 
KEYLESS-GO is within 3 ft (1 m) of the 
vehicle and:
the door handle is splashed with 
water, or
you attempt to clean the door 
handle. 
Warning!
G
When leaving the vehicle, always remove the 
SmartKey from the starter switch, 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. It is possible for children 
to open a locked door from the inside, which 
could result in an accident and/or serious 
personal injury. 
Page 95 of 464
95 Controls in detail
Locking and unlocking
Locking the vehicle
1Lock button at trunk
Press the lock button 1.
or
Press the lock button at the driver’s 
door (
page 56).
or
Vehicles with trunk lid opening/closing 
system*, press the KEYLESS-GO lock-
ing/closing switch at the trunk lid 
(page 104).
The vehicle locks. The turn signals 
blinks three times to confirm locking.Checking the batteries
Press button‹ orŒ.
Battery check lamp5 comes on brief-
ly to indicate that the SmartKey batter-
ies are in order.
!If you can no longer lock or unlock the 
vehicle with the SmartKey with 
KEYLESS-GO, then the batteries in the 
SmartKey are discharged, the 
SmartKey with KEYLESS-GO is mal-
functioning or the vehicle battery is 
drained.
Check the batteries in the 
SmartKey and replace them if nec-
essary (
page 350).
Use the mechanical key to unlock 
the doors (
page 348) and the 
trunk (
page 349).
Have the vehicle battery and the 
battery connections checked.
Use the mechanical key to lock the 
doors and the trunk (if applicable) 
(page 349).
If the SmartKey is malfunctioning, con-
tact an authorized Mercedes-Benz Cen-
ter.
!If battery check lamp5 does not 
come on briefly during check, then the 
SmartKey batteries are discharged.
Replace the batteries (
page 350). 
You can obtain the required batteries 
at any authorized Mercedes-Benz Cen-
ter.
iIf the batteries are checked within sig-
nal range of the vehicle, pressing 
the‹ orŒ button will lock or 
unlock the vehicle accordingly. 
Page 97 of 464
97 Controls in detail
Locking and unlocking
Loss of the SmartKey with KEYLESS-GO
If you lose your SmartKey with 
KEYLESS-GO, you should do the following:
Have the SmartKey with KEYLESS-GO 
deactivated by an authorized 
Mercedes-Benz Center.
Report the loss immediately to your car 
insurance company.
Have the mechanical lock replaced if 
necessary.
Your 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.
1Locking knob
2Inside door handle
Pull on door handle2.
If door was locked, locking knob1 will 
move up.
iIf the vehicle has previously been 
locked from the outside with the 
SmartKey, opening a door from the in-
side will trigger the anti-theft alarm sys-
tem.
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*
Grasp the outside door handle.
Press the KEYLESS-GO* start/stop 
button. 
Page 98 of 464
98 Controls in detailLocking and unlocking
Opening the trunk
Opening the trunk from outside 
(vehicles without KEYLESS-GO*)
A minimum height clearance of 5.41 ft 
(1.65 m) is required to open the trunk lid.
The handle is located in the rear license 
plate recess.
1Handle
Pull on handle1.
The trunk opensThe trunk can also be opened using the 
SmartKey (
page 90) or from its inside in 
an emergency, see “Trunk lid emergency 
release” (
page 105).
iIf you open a door, the side windows on 
that side of the vehicle will lower slight-
ly. The windows close again when you 
close the door.
!The trunk lid swings open upwards au-
tomatically. Always make sure there is 
sufficient overhead clearance.iIf the trunk lid does not open, it is still 
locked separately (if applicable) 
(page 106).
The vehicle must be unlocked. 
Page 100 of 464
100 Controls in detailLocking and unlockingClosing the trunk
1Handle
Lower trunk lid by pulling firmly on 
handle1.
Close trunk lid with hands placed flat 
on it.
Trunk lid opening/closing system*
Opening the trunk from the inside
You can open the trunk from the inside if 
the vehicle is stationary.
A minimum height clearance of 5.41 ft 
(1.65 m) is required to open the trunk lid.
The switch for opening and closing the 
trunk is located on the driver’s door.
1Remote trunk lid opening switch
2Remote trunk lid closing switch
Press remote trunk lid opening 
switch1 until the trunk lid begins to 
open.
Warning!
G
To prevent possible personal injury, always 
keep hands and fingers away from the trunk 
lid opening when closing the trunk. Be espe-
cially careful when small children are 
around.
Warning!
G
Only drive with the trunk closed. Among oth-
er dangers, such as your view being blocked, 
exhaust fumes may enter the vehicle 
interior.iDo not place the SmartKey in the open 
trunk. You may lock yourself out.iVehicles with KEYLESS-GO*:
To prevent a possible inadvertent lock-
out, the trunk lid will open automatical-
ly if a SmartKey with KEYLESS-GO* is 
recognized inside the vehicle or in the 
trunk.