Page 102 of 474

100 Controls in detailLocking and unlockingSelective setting
If you frequently travel alone, you may wish 
to reprogram the SmartKey with 
KEYLESS-GO so when you, grasp the driv-
er’s outside door handle only the driver’s 
door and the fuel filler flap unlocks.
Press and hold buttonsŒ and‹ 
simultaneously for about six 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 outside door handle.
All turn signal lamps flash once. The 
locking knob in the driver's door moves 
up. The anti-theft alarm system is dis-
armed.Global unlocking
Grasp any outside door handle other 
than the driver’s outside door handle.
All turn signal lamps flash once. The 
locking knobs in the doors move up. 
The anti-theft alarm system is dis-
armed.
Global locking
Press lock button at outside door han-
dle (
page 58).
All turn signal lamps flash 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 six seconds 
until battery check lamp5 flashes 
twice.
iYou can also lock the vehicle using the 
lock button at trunk lid (
page 101) 
or, vehicles with trunk lid 
opening/closing system*, 
KEYLESS-GO locking/closing switch 
(
page 110).
!If you can not lock or unlock the vehicle 
with the SmartKey with KEYLESS-GO, 
then either the battery in the SmartKey 
with KEYLESS-GO is discharged, the 
SmartKey with KEYLESS-GO is mal-
functioning or the vehicle battery is 
drained.
Check the battery in the SmartKey 
with KEYLESS-GO and replace it if 
necessary (
page 387).
Use the mechanical key to unlock 
the driver’s door (
page 383) and 
trunk (
page 384). 
Use the mechanical key to lock the 
driver’s door (
page 383). 
     
        
        Page 103 of 474

101 Controls in detail
Locking and unlocking
Checking the battery
Press button‹ orŒ.
Battery check lamp5 comes on brief-
ly to indicate that the SmartKey with 
KEYLESS-GO battery is in order.Global locking using the lock button at 
trunk lid
1Vehicle lock button
Press vehicle lock button1.
All turn signal lamps flash three times. 
The locking knobs in the doors move 
down. The anti-theft alarm system is 
armed.
Have the vehicle battery and the 
battery connections checked 
(page 403).
If the SmartKey with KEYLESS-GO is 
malfunctioning, contact an authorized 
Mercedes-Benz Center.
!If battery check lamp5 does not 
come on briefly during check, the 
SmartKey battery with KEYLESS-GO is 
discharged.
Replace the battery (
page 387). 
You can obtain the required battery at 
any authorized Mercedes-Benz Center.
iIf the battery is checked within signal 
range of the vehicle, pressing the 
button‹ orŒ will lock or unlock 
the vehicle accordingly.iTo prevent a possible inadvertent lock-
out, the trunk will open automatically if 
a SmartKey with KEYLESS-GO is recog-
nized inside the vehicle or in the trunk. 
iYou can also lock the vehicle using the 
lock button at outside door handle 
(page 58) or, vehicles with trunk lid 
opening/closing system*, 
KEYLESS-GO locking/closing switch 
(page 110). 
     
        
        Page 139 of 474

137 Controls in detail
Lighting
Interior lighting
The controls are located in the overhead 
control panel.
1Left reading lamp on/off
2Rear interior lamps on/off
3Right reading lamp on/off
4Rocker switch for automatic 
control on/offAutomatic control
Activating
Press rocker switch 4 to the center 
position.
The interior lighting switches on in 
darkness when you:
unlock the vehicle
remove the SmartKey from the 
starter switch
open a door
open the trunk
The interior lighting switches off automati-
cally following an adjustable time delay.
For more information, see “Setting interior 
lighting delayed shut-off” (
page 167).Deactivating
Press the ñ symbol on rocker 
switch 4.
The interior lighting remains switched 
off in darkness, even when you:
unlock the vehicle
remove the SmartKey from the 
starter switch
open a door
open the trunk
Manual control
Front interior lighting
Press the ð symbol on rocker 
switch 4.
The front interior lighting switches on.
Press the ñ symbol on rocker 
switch 4 again.
The front interior lighting switches off. 
The automatic control function is acti-
vated.
iLeaving an interior light switch in the 
ON position for extended periods of 
time with the engine turned off could 
result in a discharged battery.
iIf the door remains open, the interior 
lighting switches off automatically after 
approximately five minutes. 
     
        
        Page 205 of 474

203 Controls in detail
Automatic climate control
Activating
Moist air can fog up the windows. You can 
dehumidify the air with the air condition-
ing.
Press± again (
page 194). 
The indicator lamp on the ± button 
goes out.
The air conditioning uses the refrigerant 
R134a. This refrigerant is free of CFCs 
which are harmful to the ozone layer.
Residual heat and ventilation
With the engine switched off, it is possible 
to continue to heat or ventilate the interior 
for up to 30 minutes. This feature makes 
use of the residual heat produced by the 
engine.
Activating
Turn the SmartKey in the starter switch 
to position1 or 0, or remove it from the 
starter switch.
Press buttonT (
page 194).
The indicator lamp on buttonT 
comes on.Deactivating
Press buttonT (
page 194).
The indicator lamp on buttonT 
goes out.
The residual heat is automatically turned 
off:
when the ignition is switched on
after about 30 minutes
if the battery voltage drops
!If the± button on the automatic cli-
mate control panel starts to flash, this 
indicates that the air conditioning is 
losing refrigerant. The compressor has 
turned itself off. The air conditioning 
cannot be turned on again.
Have the air conditioning checked at 
the nearest authorized Mercedes-Benz 
Center.
iHow long the system will provide heat-
ing depends on the coolant tempera-
ture and the temperature set by the 
operator. The blower will run at speed 
setting 1 regardless of the air distribu-
tion control setting. 
     
        
        Page 339 of 474
337 Practical hints
What to do if …?
Where will I find ...?
Unlocking/locking in an emergency
Opening/closing in an emergency
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Battery
Jump starting
Towing the vehicle
Fuses 
     
        
        Page 366 of 474

364 Practical hintsWhat to do if …?Display 
Possible cause
Possible solution
_ 
ENTRY POSITION
DO NOT DRIVE
Seat, exterior mirrors and steering wheel 
have not yet moved to their preset driving 
positions.
Wait until the seat, exterior mirrors and 
steering wheel have moved to their driv-
ing positions.
The message will disappear.
Y
 
HOOD OPEN!
You are driving with the hood open.
Close the hood (
page 287).
I 
REMOVE KEY!
You have forgotten to remove the 
SmartKey.
Remove the SmartKey from the ignition.
REPLACE KEY!
DRIVE TO WORKSHOP
The SmartKey is malfunctioning.
Visit an authorized Mercedes-Benz Cen-
ter as soon as possible.
AUTOMATIC LIGHT ON 
REMOVE KEY!
SmartKey in starter switch position 1 
or2.
Remove the SmartKey from the starter 
switch.
KEY
CHECK BATTERY
The battery in the KEYLESS-GO* key is 
discharged.
Replace the battery (
page 387).
KEY
NOT RECOGNIZED
SmartKey with KEYLESS-GO* is not rec-
ognized while the engine is running be-
cause
the SmartKey is not in the vehicle
there is strong radio-frequency inter-
ference
Stop the vehicle as soon as it is safe to do 
so.
Search for the SmartKey.
Otherwise the vehicle cannot be centrally 
locked nor can the engine be started again 
after it has been stopped. 
     
        
        Page 372 of 474

370 Practical hintsWhat to do if …?Display 
Possible cause
Possible solution
<
SEAT BELT SYSTEM
DRIVE TO WORKSHOP
The seat belt system is malfunctioning.
Visit an authorized Mercedes-Benz 
Center as soon as possible.
K 
CLOSE
SUNROOF!
You have opened the driver’s door with 
the SmartKey removed from the starter 
switch and the tilt/sliding sunroof open.
Close the tilt/sliding sunroof 
(page 211).
J 
CLOSE
SUNROOF!
You have opened the driver’s door with 
the SmartKey removed from the starter 
switch and the tilt/sliding sunroof open.
Close the tilt/sliding sunroof 
(page 211).
L 
TELE AID
DRIVE TO WORKSHOP
One or more main functions of the Tele 
Aid system are malfunctioning.
Have the Tele Aid system checked by an 
authorized Mercedes-Benz Center.
TELE AID BATTERY
DRIVE TO WORKSHOP
The emergency power battery for the Tele 
Aid system is malfunctioning. If the vehi-
cle battery is also discharged, Tele Aid 
will not be operational.
Have the Tele Aid system checked by an 
authorized Mercedes-Benz Center.
t
FUNCTION
UNAVAILABLE
This display appears if button t or 
s on the multifunction steering wheel 
is pressed and the vehicle is not equipped 
with a telephone. 
     
        
        Page 389 of 474

387 Practical hints
Replacing SmartKey batteries
Replacing SmartKey batteries
If the batteries in the SmartKey or the 
SmartKey with KEYLESS-GO* are dis-
charged, the vehicle can no longer be 
locked or unlocked. It is recommended to 
have the batteries replaced at an autho-
rized Mercedes-Benz Center.Batteries contain materials that can harm 
the environment if disposed of improperly. 
Recycling of batteries is the preferred 
method of disposal. Many states require 
sellers of batteries to accept old batteries 
for recycling.
SmartKey
Remove mechanical key out of the 
SmartKey (
page 383).1Mechanical key
2Battery compartment
Replacement batteries: Lithium, type 
CR 2025 or equivalent.
Insert the mechanical key1 in side 
opening and push gray slide.
The battery compartment2 is un-
latched.
Pull battery compartment2 out of the 
housing in direction of arrow.
Remove the batteries.
Warning!
G
Batteries contain poisonous and corrosive 
substances. Therefore keep the batteries 
out of reach of children.
If a battery is swallowed, seek medical help 
immediately.
iWhen inserting the batteries, make 
sure they are clean and free of lint.iWhen changing batteries, always re-
place both batteries.
The required replacement batteries are 
available at any authorized 
Mercedes-Benz Center.