Page 97 of 498

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 power 
windows (
page 249) and power 
tilt/sliding sunroof* (
page 253) 
using the SmartKey. 
     
        
        Page 101 of 498

99 Controls in detail
Locking and unlocking
SmartKey with KEYLESS-GO*
Vehicles equipped with KEYLESS-GO come 
with two SmartKeys with KEYLESS-GO, 
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 dis-
tinguish 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.
If the SmartKey with KEYLESS-GO is valid, 
your vehicle unlocks
the doors
the trunk lid
the fuel filler flap
SmartKey with remote controls1‹ Lock button
2Š Opening button for trunk lid
3Mechanical key locking tab
4Œ Unlock button
5Battery check lamp
6Â Panic button (
page 83)
For more information on using the 
SmartKey buttons, see “SmartKey” 
(
page 94) iWhen the passenger outside door han-
dle is pulled, the vehicle is centrally un-
locked.
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. Unsupervised use of vehi-
cle equipment may cause an accident 
and/or serious personal injury.!To prevent possible malfunction, avoid 
exposing the SmartKey with 
KEYLESS-GO to high levels of electro-
magnetic radiation.iYou can also open and close the power 
windows (
page 249) and power 
tilt/sliding sunroof* (
page 253) us-
ing the SmartKey. 
     
        
        Page 108 of 498
106 Controls in detailLocking and unlocking
Opening the trunk 
Opening the trunk from outside 
(vehicles without KEYLESS-GO*)
A minimum height clearance of 5.71 ft 
(1.74 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 181 of 498

179 Controls in detail
Good visibility
Warning!
G
The auto-dimming function does not react if 
incoming light is not aimed directly at sen-
sors in the interior rear view mirror.
The interior rear view mirror and the exterior 
rear view mirror on the driver’s side do not 
react, for example, if the rear window sun 
shade* is in raised position.
Glare can endanger you and others.
Warning!
G
In the case of an accident, liquid electrolyte 
may escape from the mirror housing if the 
mirror glass breaks.
Electrolyte has an irritating effect. Do not 
allow the liquid to come into contact with 
eyes, skin, clothing, or respiratory system. 
In case it does, immediately flush affected 
area with water, and seek medical help if 
necessary.!Electrolyte drops coming into contact 
with the vehicle paint finish can be 
completely removed only while in the 
liquid state and by applying plenty of 
water.
Warning!
G
Exercise care when using the passen-
ger-side exterior rear view mirror. The mirror 
surface is convex (outwardly curved surface 
for a wider field of view). Objects in mirror 
are closer than they appear. Check your 
interior rear view mirror or glance over your 
shoulder before changing lanes. 
     
        
        Page 183 of 498
181 Controls in detail
Good visibility
Sun 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 184 of 498

182 Controls in detailGood visibilityRear window sunshade*
The switch is located in the center console.
1Rear window sunshade switch
Switch on ignition (
page 36).
Always raise the sunshade fully for its sup-
port against the window frame.Raising the sunshade
Press switch1 briefly.
The sunshade is raised completely.
Stopping the raising procedure
Press switch1 again.
The sunshade stops.
Lowering the sunshade
Press switch1 briefly.
The sunshade is lowered completely.
Stopping the lowering procedure
Press switch1 again.
The sunshade stops.
!Make sure that the movement of the 
rear window sunshade is not restricted 
by objects on the rear window shelf. 
Otherwise, the sunshade or the objects 
could be damaged.
Warning!
G
When operating the rear window sunshade, 
make sure there is no danger of anyone be-
ing harmed by the raising or lowering 
procedure.
The raising or lowering procedure can be 
immediately halted by briefly pressing the 
switch
1
.
Briefly press switch
1
 again to raise or low-
er the rear window sunshade completely.
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 185 of 498

183 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 
climate control panel (
page 195) or 
in automatic climate control panel 
(
page 195).
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 187 of 498
185 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