Page 80 of 498

78 Safety and SecurityOccupant safety
Self-test Occupant Classification 
System
After turning the SmartKey in the starter 
switch to position1 or2 or pressing the 
KEYLESS-GO* start/stop button once or 
twice, the 56 indicator lamp1 lo-
cated in the center console illuminates. If 
an adult occupant is properly sitting on the 
front passenger seat and the system sens-
es the occupant as being an adult, the 
56 indicator lamp will illuminate 
and go out after approximately six 
seconds. 
If the seat is not occupied and the system 
senses the front passenger seat as being 
empty, the 56 indicator lamp will 
illuminate and not go out. 
Warning!
G
If the 1indicator lamp and the 
56indicator lamp are lit at the same 
time, there is a malfunction in the Occupant 
Classification System. The front passenger 
front air bag will be deactivated in this case.
In order to ensure proper operation of the 
air bag system and OCS:
Have the system checked as soon as 
possible by qualified technicians. Con-
tact an authorized Mercedes-Benz 
Center.
Sit properly belted in a nearly upright 
position with your back against the seat 
backrest.
Do not lean on the armrests or lift your-
self from the seat by using the handle 
over the door as this may cause the OCS 
to be unable to correctly approximate 
the occupant weight category.
Only have the seat repaired or replaced 
by an authorized Mercedes-Benz 
Center.
Read and observe all warnings in this 
chapter. 
     
        
        Page 92 of 498

90 Safety and SecurityAnti-theft systemsAnti-theft alarm system
Once the alarm system has been armed, a 
visual and audible alarm is triggered when 
someone opens
a door
the trunk
the hood.
The alarm system will also be triggered 
when
someone attempts to raise the vehicle 
(page 91)
opening the vehicle with the 
mechanical key.Arming the alarm system
The indicator lamp is in the switch for the 
tow-away alarm in the center console.
1Indicator lamp
Lock the vehicle with the SmartKey or 
KEYLESS-GO*.
The turn signal lamps flash three times 
to indicate that the alarm system is 
activated. Indicator lamp1 begins to 
flash after approximately 30 seconds 
after arming the alarm system.
iThe alarm will stay on, even if the 
activating element (a door, for 
example) is immediately closed.
iIf the alarm stays on for more than 
30 seconds, a call to the Response 
Center is initiated automatically by the 
Tele Aid system (
page 280) provided 
Tele Aid service was subscribed to and 
properly activated, and that necessary 
cellular service and GPS coverage are 
available.
iIf the turn signal lamps do not flash 
three times, one of the following 
elements may not be properly closed:
a door
the trunk lid
the hood
Close the respective element and lock 
the vehicle again. 
     
        
        Page 94 of 498

92 Safety and SecurityAnti-theft systemsArming tow-away alarm
Lock the vehicle with the SmartKey or 
KEYLESS-GO*.
The tow-away alarm is automatically 
armed after about 30 seconds.
Disarming tow-away alarm
To prevent triggering the tow-away alarm, 
switch off the tow-away alarm feature 
before towing the vehicle, or when parking 
on a surface subject to movement, such as 
a ferry or auto train.The switch is located on the center 
console.
1Tow-away alarm off switch
2Indicator lamp
Switch off the ignition and remove the 
SmartKey.
Press switch1.
Indicator lamp2 in switch1 comes 
on briefly.
Exit and lock your vehicle with the 
SmartKey or (vehicles with 
KEYLESS-GO*) the lock button at each 
door handle.
The tow-away alarm remains disarmed 
until you lock your vehicle again.
Canceling the alarm
To cancel the alarm:
With the SmartKey
Press the Œ or ‹ button on the 
SmartKey.
or
Insert the SmartKey in the starter 
switch.
With KEYLESS-GO*
Pull the outside door handle.
or
Press the KEYLESS-GO start/stop 
button.
iWhen you unlock the vehicle, the 
tow-away protection disarms 
automatically. The tow-away alarm 
remains disarmed until you lock the 
vehicle again
iYou cannot disarm the tow-away alarm 
while the ignition is switched on. 
     
        
        Page 112 of 498

110 Controls in detailLocking and unlockingAutomatic 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) or more.
You can open a locked door from the 
inside. Open doors only when conditions 
are safe to do so.
You can deactivate the automatic locking 
mode using the control system, see “Set-
ting automatic locking” (
page 158).
Locking and unlocking from the inside
You can lock or unlock the doors and the 
trunk from inside using the central locking 
or unlocking switch. This can be useful, for 
example, if you want to lock the vehicle 
before starting to drive.
You cannot lock or unlock the fuel filler flap 
with the central locking or unlocking 
switch.The switch is located in the center console.
1Central locking switch
2Central unlocking switch
iThe doors unlock automatically after an 
accident if the force of the impact 
exceeds a preset threshold.
To prevent the vehicle door locks from 
locking, deactivate the automatic 
central locking when the vehicle
is pushed or towed
is on a test stand
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 118 of 498
116 Controls in detailSeatsFolding head restraints back with re-
lease button
1Release button
Push release button1.
The head restraints will fold backward.Folding head restraints back with 
switch in the center console
1Rear head restraints folding switch
Start the engine (
page 46).
Press switch1 to release the head re-
straints.
The head restraints will fold backward.Placing rear head restraints upright
Pull the rear head restraint forward un-
til it locks into position.
iYou can also fold the head restraints 
back using the switch in the center 
console.
Warning!
G
Make sure the head restraints engage when 
placing them upright. Otherwise their pro-
tective function cannot be assured. 
     
        
        Page 121 of 498

119 Controls in detailSeats
Seat heating*
Both switches for the front seats are 
located in the center console.
1Seat heating switchThe red indicator lamps on the switch1 
show which heating level you have select-
ed.
Switch on ignition (
page 36).
All the lamps in the instrument cluster 
come on.Switching on seat heating
Press seat heating switch1 twice.
Three red indicator lamps in the switch 
come on.
Continue pressing seat heating 
switch1 until desired seat heating 
level is reached.
Switching off seat heating
Press seat heating switch1 
repeatedly until all red indicator lamps 
go out.
Level3
Three indicator lamps on.
After approximately five minutes, 
seat heating is automatically 
switched to level 2.
2
Two indicator lamps on.
After approximately ten minutes, 
seat heating is automatically 
switched to level 1.
1
One indicator lamp on.
After approximately 20 minutes, 
seat heating is automatically 
switched off.
off
No indicator lamp on.
iIf one or all of the indicator lamps flash 
on the seat heating switch1, there is 
insufficient voltage due to too many 
electrical consumers being switched 
on. The seat heating switches off auto-
matically.
The seat heating will switch back on 
again automatically as soon as 
sufficient voltage is available. 
     
        
        Page 122 of 498

120 Controls in detailSeatsSeat ventilation*
Both switches for the front seats are 
located in the center console.
1Seat ventilation switchThe blue indicator lamps in the switch1 
show which ventilation level you have 
selected: 
Switch on ignition (
page 36).
All lamps in the instrument cluster 
come on.
Switching on seat ventilation
Press seat ventilation switch1.
Three blue indicator lamps come on. 
Press seat ventilation switch1 
repeatedly until the desired seat venti-
lation level is reached.Switching off seat ventilation
Press seat ventilation switch1 
repeatedly until all blue indicator lamps 
go out.
Level3
Three indicator lamps on
2
Two indicator lamps on
1
One indicator lamp on
off
No indicator lamp on
iIf one or all of the indicator lamps flash 
on the seat ventilation switch1, there 
is insufficient voltage due to too many 
electrical consumers being switched 
on. The seat ventilation switches off au-
tomatically.
The seat ventilation will switch back on 
again automatically as soon as suffi-
cient voltage is available. 
     
        
        Page 133 of 498

131 Controls in detail
Lighting
Driving rearward
Switching on cornering fog lamps
Place the gear selector lever in 
positionR.
The inverse front fog lamp comes on 
automatically depending on the steer-
ing direction and steering angle.
Switching on cornering fog lamps
Place the gear selector lever out of 
positionR.
The respective front fog lamp goes out.
Hazard warning flasher
The hazard warning flasher can be 
switched on at all times, even with the 
SmartKey or the SmartKey with 
KEYLESS-GO* removed from the starter 
switch or with the SmartKey with 
KEYLESS-GO* removed from the vehicle.
The hazard warning flasher switches on 
automatically when an air bag deploys.
The hazard warning flasher switch is 
located on the upper part of the center 
console.
1Hazard warning flasher switchSwitching on hazard warning flasher
Press hazard warning flasher 
switch1.
All turn signals are flashing.
Switching off hazard warning flasher
Press hazard warning flasher switch1 
again.iWith the hazard warning flasher 
activated and the combination switch 
set for either left or right turn, only the 
respective turn signals will operate 
when the ignition is switched on.iIf the hazard warning flasher has been 
activated automatically, press hazard 
warning flasher switch1 once to 
switch it off.