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32 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index
Start lock-out
Important!
Operating with electronic key:
Removing the electronic key from the starter switch 
activates the start lock-out. The engine cannot be 
started.
Inserting the electronic key in the starter switch 
deactivates the start lock-out.
Operating with KEYLESS-GO:
Turning off the engine with the start- / stop button on 
the gear selector lever activates the start lock-out. For 
turning off the engine with KEYLESS-GO, see page 232.
Starting the engine with the start- / stop button 
deactivates the start lock-out, if a valid KEYLESS-GO-
card is recognized inside the vehicle. For starting the 
engine with KEYLESS-GO, see page 231. The engine 
cannot be started with a KEYLESS-GO-card outside the 
vehicle.Note:
In case the engine cannot be started (vehicle’s battery is 
in order), the system is not operational. Contact an 
authorized Mercedes-Benz Center or call 1-800-FOR-
MERCedes (in the USA), or 1-800-387-0100 (in Canada). 
         
        
        
     
        
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33 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index General notes on the central locking system
If the electronic key is inserted in the starter switch, the 
vehicle cannot be locked or unlocked with the remote 
control.
If the vehicle cannot be locked or unlocked:
•Aim transmitter eye at a receiver on either front 
door handle. Check the batteries of the electronic 
main key, see page 363, or synchronize the remote 
control, see page 365.
•Use the mechanical key to unlock the vehicle. To 
start engine, insert the electronic key in the starter 
switch. There could be a slight delay until the 
electronic key can be turned in the starter switch.
•Vehicles with KEYLESS-GO only:
A KEYLESS-GO-card must be recognized by the 
system as being outside the vehicle to enable the 
vehicle to be locked or unlocked (maximum distance 
between card and doors or trunk is approx. 3 ft. 
(1 m). Check the location of the KEYLESS-GO-card, 
see page 38. Check the batteries of the KEYLESS-
GO-card, see page 366. The trunk lid will open 
automatically if a  KEYLESS-GO card is detected in 
the trunk, see page 38.Note:
If neither the remote control nor KEYLESS-GO system 
functions, use the mechanical key to unlock or lock the 
vehicle. To start engine, insert the electronic key in the 
starter switch. There could be a slight delay until the 
electronic key can be turned in the starter switch.
Important!
When unlocking the driver’s door with the mechanical 
key, the exterior lamps will flash and the alarm will 
sound.
To cancel the alarm, insert the electronic key in the 
starter switch, or press buttonŒ or‹ on the 
electronic main key; or with the optional KEYLESS-GO-
system, when carrying a KEYLESS-GO-card, by grasping 
a door handle or pressing the start- / stop button on the 
gear selector lever. 
         
        
        
     
        
        Page 41 of 421

38 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index
KEYLESS-GO
Important!
For the KEYLESS-GO-system to function properly, the 
operator should observe the following:
•The driver should carry the KEYLESS-GO-card with 
him / her.
•To avoid radio transmission interference, never store 
the KEYLESS-GO-card together with other electronic 
items (e.g. cellular telephones, other KEYLESS-GO-
cards) or metallic objects (e.g. coins, metal foil).
•To lock or unlock the vehicle, the card must be 
recognized by the system as being located outside 
the vehicle. The card must be in close proximity to a 
door or the trunk lid (approx. 3 ft. [1 m]). To activate 
the start / stop button function, the KEYLESS-GO-
card must be recognized by the system as being 
located inside the vehicle.
•If the KEYLESS-GO-card is positioned farther away 
from the vehicle (e.g. inside clothing or a briefcase) 
and can no longer be recognized by the system, the 
vehicle cannot be locked or the engine started via 
the KEYLESS-GO-system.•If the KEYLESS-GO-card is removed from the vehicle 
while the engine is running, or by placing the card 
in front of the center armrest (see page 195), the 
message “CHIP-CARD – NOT RECOGNIZED!” will 
appear repeatedly in the multifunction display, 
seepage322.
Find the card or change its present location (e.g. 
place it on the front passenger seat or insert it in 
shirt pocket).
•If the message “CHIP - CARD – NOT RECOGNIZED” 
is ignored for an extended of time (approx. 
15 minutes), the engine could stop by itself during a 
vehicle stop (e.g. traffic light). The vehicle can then 
no longer be centrally locked or the engine 
restarted. You must first find the card or change its 
present location (e.g. place it on the front passenger 
seat or insert it in shirt pocket). Start the engine 
again. See page 228.
•Do not forget, the engine can be started by anyone 
with a KEYLESS-GO-card that is left inside the 
vehicle. Leaving the chip-card behind when exiting 
and locking the vehicle, the message “CHIP-CARD –
STILL IN VEHICLE” appears in the multifunction 
display, see page 322. 
         
        
        
     
        
        Page 42 of 421

39 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index •Opening the driver’s door with the engine shut off 
and no electronic key in the starter switch, the 
message “CHIP-CARD – DO NOT FORGET” appears 
as a reminder, see page 322. 
Important!
In the case of a malfunction in the KEYLESS-GO-system, 
we recommend that you carry the electronic key plus 
mechanical key with you and keep them in a safe place 
so that they are always handy. Never leave the electronic 
key in the vehicle.Notes:
The KEYLESS-GO-function also permits closing of 
windows and sliding / pop-up roof (convenience feature), 
see page 46.
With the KEYLESS-GO-card in close proximity (approx. 
3 ft. [1 m]) of the vehicle, aiming a jet of water at a door 
handle (e.g. when washing the vehicle) or cleaning 
snow from a door could lock or unlock the vehicle 
inadvertently.
To prevent a possible inadvertent lockout, the trunk lid 
will open automatically if a KEYLESS-GO-card is 
recognized in the area of the rear shelf or inside the 
trunk. 
         
        
        
     
        
        Page 43 of 421

40 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index
Locking and unlocking with KEYLESS-GO-card
Unlocking:
Grasp any door handle. All turn signal lamps blink once 
to indicate that the vehicle is unlocked.
The KEYLESS-GO-card can be programmed for two 
kinds of unlocking modes (see below):
Selective unlocking mode –
Grasp driver’s door handle to unlock driver’s door and 
fuel filler flap.
Grasping the passenger door or a rear door, centrally 
unlocks the vehicle.
Global unlocking mode –
Grasp any door handle to unlock both doors, fuel filler 
flap, and trunk.
For choosing global or selective mode on KEYLESS-GO-
card, see page 43.Notes:
The door which was unlocked, can be opened 
immediately after the audible click. The other door can 
be opened after its lock button rises up.
If the trunk was previously locked separately, it will 
remain locked, see page 53.
The presently active unlocking mode (selective or 
global) can be determined by pressing the button on the 
KEYLESS-GO-card (see page 43 for changing mode).
If within 40 seconds of unlocking with the 
KEYLESS-GO-card, neither door nor trunk is opened, 
the electronic key is not inserted in the starter switch, 
or the central locking switch is not activated, the vehicle 
will automatically lock. 
         
        
        
     
        
        Page 44 of 421
41 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Locking:
Press lock button (1) at any door. All turn signal lamps 
blink three times to indicate that the vehicle is locked. If 
they do not blink three times, a door or trunk is not 
properly closed, or the KEYLESS-GO-card is still in the 
vehicle. Check the multifunction display, see page 322.Note:
Locking the vehicle with the door lock button (1) is only 
possible if a KEYLESS-GO-card is outside the vehicle.
P80.00-2040-26
1 
         
        
        
     
        
        Page 45 of 421
42 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index
Unlocking:
Press trunk lid lock (2) to open trunk only.
Locking:
Press the trunk lid lock button (3). All turn signal lamps 
blink three times to indicate that the vehicle is locked. If 
they do not blink three times, a door or trunk is not 
properly closed or a KEYLESS-GO-card is still in the 
vehicle. Check the multifunction display, see page 322.Notes:
If the trunk was previously locked separately, it will 
remain locked, see page 53.
The vehicle cannot be centrally unlocked via the trunk 
lid lock (2).
To prevent a possible inadvertent lockout, the trunk lid 
will open automatically if a KEYLESS-GO-card is 
recognized in the area of the rear shelf or inside the 
trunk.
P54.25-2457-26 
         
        
        
     
        
        Page 46 of 421
43 Central locking system
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Choosing global or selective mode 
on KEYLESS-GO-card
To choose between the selective or global opening mode 
press and hold button (1) until the indicator lamp at the 
requested symbol (2) or (3) comes on.Checking last KEYLESS-GO-card locking mode
Briefly press button (1). The indicator lamp (2) or (3) 
lights up in red (vehicle locked) or in green (vehicle 
unlocked).
P80.30-2027-26
1
2
3