Page 59 of 506

58 Getting startedParking and locking
1Lock button on the door handle
After exiting the vehicle, press lock 
button1 on the door handle or on the 
trunk lid.
With the hood, trunk and both doors 
closed, all turn signal lamps flash three 
times. The locking knobs in the doors 
move down. The anti-theft alarm sys-
tem is armed.
For more information, see “Locking and 
unlocking” (
page 94).
!If you hear a warning signal you have 
either
forgotten to switch off the vehicle’s 
exterior lamps before opening the 
driver’s door, or
tried to turn off the engine while the 
gear selector lever is not inP.
Turn off the lights or place the gear se-
lector lever inP.
iOpening a door causes the windows on 
that side of the car to open slightly. 
They will return to the up position when 
the door is closed.
Warning!
G
To prevent possible personal injury, always 
keep hands and fingers away from the door 
openings when closing the doors. Be espe-
cially careful when small children are 
around.
Before closing doors, make sure there is no 
possibility of someone getting caught in a 
door during closing.
Warning!
G
When leaving the vehicle, always remove the 
SmartKey or SmartKey with KEYLESS-GO* 
from the starter switch, take it 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.
 
     
        
        Page 62 of 506

61 Safety and Security
Occupant safety
Air bags
Warning!
G
In the event that the 1indicator lamp 
comes on during driving or does not come 
on at all, the SRS self-check has detected a 
malfunction. For your safety, we strongly 
recommend that you visit an authorized 
Mercedes-Benz Center immediately to have 
the system checked; otherwise the SRS may 
not deploy when needed in an accident, 
which could result in serious or fatal injury, 
or it might deploy unexpectedly and unnec-
essarily which could also result in injury.
In addition, improper repair work on the SRS 
creates a risk of rendering the SRS inopera-
tive or causing unintended air bag deploy-
ment. Work on the SRS must therefore only 
be performed by qualified technicians. Con-
tact an authorized Mercedes-Benz Center.
If it is necessary to modify an air bag system 
to accommodate a person with disabilities, 
contact your local authorized 
Mercedes-Benz Center or call our Customer 
Assistance Center at 1-800-FOR-MERCedes 
(1-800-367-6372) for details.
Warning!
G
Air bags are designed to reduce the poten-
tial of injury and fatality in certain frontal im-
pacts (front air bags) or side impacts 
(head-thorax air bags and rear side-impact 
air bags). However, no system available to-
day can totally eliminate injuries and 
fatalities.
The deployment of the air bags temporarily 
releases a small amount of dust from the air 
bags. This dust, however, is neither injurious 
to your health, nor does it indicate a fire in 
the vehicle. The dust might cause some tem-
porary breathing difficulty for people with 
asthma or other breathing trouble. To avoid 
this, you may wish to get out of the vehicle 
as soon as it is safe to do so. If you have any 
breathing difficulty but cannot get out of the 
vehicle after the air bag inflates, then get 
fresh air by opening a window or door. 
     
        
        Page 83 of 506

82 Safety and SecurityOccupant safetyBlocking of rear side window operation
You can block the rear door window oper-
ation (for instance when you have children 
riding in the rear passenger compartment).
The override switch is located on the door 
control panel of the driver’s door.
1Deactivating override switch
2Activating override switch
3Override switchActivating override switch
Slide override switch3 to the right in 
direction2.
The rear side windows can no longer be 
operated using the respective switch 
located in the rear trim panels.
Deactivating override switch
Slide override switch3 to the left in 
direction1.
The rear side windows can be operated 
using the respective switch located in 
the rear trim panels.
For more information, see “Power win-
dows” (
page 239).
Warning!
G
Activate the override switch when children 
are riding in the back seats of the vehicle. 
The children may otherwise injure them-
selves, e.g. by becoming trapped in the win-
dow opening.
When leaving the vehicle, always remove the 
SmartKey or SmartKey with KEYLESS-GO* 
from the starter switch, take it 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 can cause an accident 
and/or serious personal injury.
iOperation of the rear side windows 
with the switches located on the door 
control panel of the driver’s door is still 
possible. 
     
        
        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 107 of 506
106 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 lid unlocks and begins to 
open.
The trunk can also be opened using 
buttonŠ on the SmartKey or from its 
inside in an emergency, see “Trunk lid 
emergency release” (
page 109).
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.
iThe vehicle must be unlocked.!The trunk lid swings open upwards au-
tomatically. Always make sure there is 
sufficient overhead clearance. 
     
        
        Page 179 of 506
178 Controls in detailGood visibilitySun visors
The sun visors protect you from sun glare 
while driving.
Swing sun visors down when you 
experience glare.1Mirror lamp
2Mirror cover
3Mounting
4Sun visor
To use mirror, lift up cover2.If sunlight enters through a side window:
disengage sun visor from mounting3. 
pivot sun visor to the side.
The sun visors are extendable.
Adjust the sun visors by pushing or 
pulling in the direction of the arrows.
Warning!
G
Do not use the vanity mirror while driving.
Keep the mirrors in the sun visors closed 
while vehicle is in motion. Reflected glare 
can endanger you and others.
iIf you disengage the sun visor from 
mounting3, mirror lamp1 will 
switch off. 
     
        
        Page 180 of 506

179 Controls in detail
Good visibility
Rear window defroster
The rear window defroster uses a large 
amount of power. To keep the battery 
drain to a minimum, switch off the 
defroster as soon as the rear window is 
clear. The defroster is automatically 
deactivated after approximately 
6 to 17 minutes of operation depending on 
the outside temperature.Activating
Press buttonF or1 in the cli-
mate control panel (
page 181) or in 
the automatic climate control panel 
(
page 191).
The indicator lamp on the button 
comes on.
Deactivating
Press buttonF or1 again.
The indicator lamp on the button goes 
out.
Warning!
G
Any accumulation of snow and ice should be 
removed from the rear window before 
driving. Visibility could otherwise be 
impaired, endangering you and others.!If the rear window defroster switches 
off too soon and the indicator lamp 
starts flashing, this means that too 
many electrical consumers are 
operating simultaneously and there is 
insufficient voltage in the battery. The 
system responds automatically by 
deactivating the rear window defroster.
As soon as the battery has sufficient 
voltage, the rear window defroster 
automatically switches on again. 
     
        
        Page 182 of 506
181 Controls in detail
Climate control (CLK 320)
Depending on production date, your vehi-
cle is equipped with either climate control 
panel design A or B.Climate control panel design A
Climate control panel design B
Item
1
Left side air vent, adjustable
2
Thumbwheel for air volume control 
for center air vents
3
Right side air vent, adjustable
4
Climate control panel
5
Right center air vent, adjustable
6
Thumbwheel for air volume control 
for right side center air vent 
7
Thumbwheel for air volume control 
for left side center air vent
8
Left center air vent, adjustableiFor draft-free ventilation, move the 
sliders for the side air vents1 and3 
and center air vents5 and  8 to the 
middle position.
Item
1
Air volume control
2
Left side temperature control
3
Right side temperature control
4
Air distribution control
5
Rear window defroster
6
AC cooling on/off (AC
OFF
 or A/C)
7
Air distribution and air volume 
(automatic mode)
8
Air recirculation
9
Defrosting