Page 90 of 464

90 Controls in detailIn the “Controls in detail” section you will 
find detailed information on how to oper-
ate the equipment installed in your vehicle. 
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.
For more information on unlocking and 
locking, see (
page 34) and (
page 56).
Locking and unlocking
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 differ-
ent color to help distinguish each Smart-
Key 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 trunk lid
the fuel filler flap
the glove box
the storage compartment under the 
armrest
SmartKey with remote control1
‹
Lock button
2
Š
Unlock button for the trunk lid
3Mechanical key locking tab
4ŒUnlock button
5Battery check lamp
6ÂPanic button (
page 78)
iWithout the antenna on the left rear 
side of the vehicle installed, the 
SmartKey signaling range is consider-
ably reduced. Hold the SmartKey in 
close proximity towards the antenna 
base when locking or unlocking the 
vehicle.  
     
        
        Page 91 of 464

91 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 
retractable hardtop using the 
SmartKey* (
page 242). 
     
        
        Page 92 of 464

92 Controls in detailLocking and unlockingFactory setting
Global unlocking
Press buttonŒ.
All turn signal lamps flash once.
The lock buttons on the doors move up. 
The anti-theft alarm system is dis-
armed (
page 85).
The vehicle will lock again automatically 
and reactivate the anti-theft alarm system 
within approximately 40 seconds of un-
locking if:
neither door nor trunk is opened
the SmartKey is not inserted in the 
starter switch
the central locking switch is not 
activatedGlobal locking
Press button‹.
With the hood, trunk and all doors 
closed, all turn signal lamps flash three 
times. The locking knobs on the doors 
move down.
The anti-theft alarm system is armed 
now (
page 85).Selective setting
If you frequently travel alone, you may wish 
to reprogram the SmartKey so that press-
ing buttonŒ only unlocks the driver’s 
door, the storage compartment under the 
armrest, the glove box, and the fuel filler 
flap.
Press and hold buttonsŒand‹ 
simultaneously for about six seconds.
Battery check lamp5 flashes twice.
The SmartKey will then function as fol-
lows:
Unlocking driver’s door and fuel filler 
flap
Press buttonŒ once.
All turn signal lamps flash once.
The lock button on the driver’s door 
move up. The anti-theft alarm system is 
disarmed (
page 85).
iIf the turn signal lamps do not flash 
three times, one of the following ele-
ments may not be properly closed:
a door 
the trunk lid
the fuel filler flap
the glove box
the storage compartment under the 
armrest
Close the respective element and lock 
the vehicle again. 
     
        
        Page 93 of 464

93 Controls in detail
Locking and unlocking
Global unlocking
Press buttonŒ twice.
All turn signal lamps flash once.
The lock buttons on the doors move up. 
The anti-theft alarm system is dis-
armed (
page 85).
Global locking
Press button‹.
With the hood, trunk and all doors 
closed, all turn signal lamps flash three 
times. The locking knobs on the doors 
move down.
The anti-theft alarm system is armed 
now (
page 85).
Restoring to factory setting
Press and hold buttonsŒand‹ 
simultaneously for about six seconds.
Battery check lamp5 flashes twice.
The SmartKey is set to the factory set-
ting again.Unlocking the trunk lid
You can unlock and open the trunk lid sep-
arately.
Press and hold buttonŠ on the 
SmartKey until the trunk lid unlocks.
For opening the trunk, see “Opening 
the trunk” (
page 95).
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, then the 
batteries in the SmartKey are dis-
charged, the SmartKey is malfunction-
ing, or the vehicle battery is drained.
Check the batteries in the 
SmartKey and replace them if nec-
essary (
page 378).
Use the mechanical key to lock/un-
lock the driver’s door (
page 374).
Use the mechanical key to lock/un-
lock the trunk lid as required 
(page 375).
Have the vehicle battery and the 
battery connections checked 
(page 396).
If the SmartKey is malfunctioning, con-
tact an authorized Mercedes-Benz 
Center.
iIf battery check lamp5 does not 
come on briefly during check, then the 
SmartKey batteries are discharged.
Replace the batteries (
page 378).
You can obtain the required batteries 
at any authorized Mercedes-Benz 
Center. 
     
        
        Page 94 of 464

94 Controls in detailLocking and unlockingLoss 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 to your car insurance 
company immediately.
If necessary have the mechanical lock 
replaced.
Your authorized Mercedes-Benz Center 
will be glad to supply you with a replace-
ment.
Opening the doors from the inside
You can open a locked door from the in-
side. Open door only when conditions are 
safe to do so.
1Inside door handle
2Locking knob
Pull on door handle1 of the desired 
door.
If the door was locked, locking knob2 
will move up.
iIf the batteries are checked within sig-
nal range of the vehicle, pressing 
button‹orŒ will lock or un-
lock the vehicle accordingly.
iIf the vehicle has previously been cen-
trally 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 fol-
lowing:
Press buttonŒor‹ on the 
SmartKey.
Insert the SmartKey in the starter 
switch.
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. 
     
        
        Page 95 of 464

95 Controls in detail
Locking and unlocking
Opening the trunk
A minimum height clearance of 5.78 ft 
(1.76 m) is required to open the trunk lid.
The handle is located above the rear 
license plate recess.
Pull on the handle.
Lift the trunk lid.
The trunk lid can also be opened from its 
inside in an emergency, see “Trunk lid 
emergency release” (
page 96).
Closing the trunk
1Handle
Lower the trunk lid using handle1.
Close the trunk lid with hands placed 
flat on the trunk lid.
iThe vehicle or trunk lid must be 
unlocked before the trunk lid can be 
opened.!When the trunk lid is lifted slightly, it 
swings open upwards automatically. 
Always make sure there is sufficient 
overhead clearance.
Warning!
G
To prevent possible personal injury, always 
keep hands and fingers away from the trunk 
lid opening when closing the trunk lid. Be es-
pecially careful when small children are 
around.
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.Warning!
G
Only drive with the trunk lid closed as, 
among other dangers such as visibility 
blockage, exhaust fumes may enter the ve-
hicle interior. 
     
        
        Page 96 of 464
96 Controls in detailLocking and unlocking
Trunk lid emergency release
The emergency release button is located 
on the inside of the trunk lid.
1Emergency release button
Briefly press emergency release 
button1.
The trunk lid unlocks and opens 
slightly.
Push up the trunk lid to fully open.Illumination of the emergency release but-
ton:
The button flashes for 30 minutes after 
opening the trunk.
The button flashes for 60 minutes after 
closing the trunk.
iDo not place the SmartKey in the open 
trunk. You may lock yourself out.iIf the vehicle was previously centrally 
locked, the trunk lid will lock automati-
cally when closed. The turn signal 
lamps will flash three times to confirm 
locking.
iThe emergency release button unlocks 
the trunk while the vehicle is standing 
still or in motion.iThe emergency release button does 
not unlock the trunk if the vehicle bat-
tery is discharged or disconnected. 
     
        
        Page 97 of 464

97 Controls in detail
Locking and unlocking
Automatic central locking
The doors and the trunk automatically lock 
when the ignition is switched on and the 
wheels are turning at vehicle speeds of 
approximately 9 mph (15 km/h).
You can open a locked door from the in-
side. Open door only when conditions are 
safe to do so.
You can deactivate the automatic locking 
using the control system, see “Setting 
automatic locking” (
page 141).
Locking and unlocking from the inside
You can lock or unlock the doors and the 
trunk from inside using the central locking 
switch. This can be useful, for example, if 
you want to lock the vehicle before starting 
to drive.
The fuel filler flap will not be locked or un-
locked with the central locking or unlock-
ing switch, respectively.
iIf the vehicle has previously been cen-
trally locked from the outside with the 
SmartKey, opening the trunk from the 
inside will trigger the anti-theft alarm 
system.
To cancel the alarm, do one of the fol-
lowing:
Press buttonŒor‹ on the 
SmartKey.
Insert the SmartKey in the starter 
switch.
iThe doors unlock automatically after an 
accident if the force of the impact ex-
ceeds a preset threshold.
To prevent the vehicle door locks from 
locking, deactivate the automatic cen-
tral locking when the vehicle
is pushed or towed
is on a test stand
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. Unsuper-
vised use of vehicle equipment may cause 
an accident and/or serious personal injury.