Page 129 of 521

128 Controls in detailLocking and unlocking
Valet locking
1Neutral position
2Locked
Close the trunk (
page 122).
Pull the mechanical key out of the
SmartKey (
page 426).
Insert the mechanical key in the trunk
lid lock.
Turn the mechanical key clockwise to
position 2 to lock the trunk.
The trunk remains locked even when the
vehicle is centrally unlocked.
Insert the mechanical key in the trunk
lid lock.
Turn the mechanical key counterclock-
wise to neutral position 1 to unlock
the trunk.
You can now open the trunk
(page 120).
iIf the emergency release button is
pressed and the vehicle was centrally
locked using the SmartKey, the exterior
lamps will flash and the alarm will
sound as the trunk opens.
To cancel the alarm, do one of the
following:
Insert the SmartKey in the starter
switch.
Press button Œ or ‹ on the
SmartKey.
In vehicles with KEYLESS-GO*
Pull an outside door handle.
The SmartKey with KEYLESS-GO
must be within 3 ft (1 m) of the ve-
hicle.
Press the KEYLESS-GO* start/stop
button (
page 37).
The SmartKey with KEYLESS-GO
must be inside the vehicle.
iTo deny any unauthorized person ac-
cess to the trunk, e.g. when you valet
park the vehicle, lock it separately with
the mechanical key. Leave only the
SmartKey or SmartKey with
KEYLESS-GO* less its mechanical key
with the vehicle.
iYou can only cancel the separate trunk
locking mode by means of the
mechanical key.
Page 130 of 521

129 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 ap-
proximately 9mph (15km/h) or more.
You can open a locked door from the in-
side. Open door only when conditions are
safe to do so.For more information on towing the vehi-
cle, see the “Practical hints” section
(
page 457).
You can deactivate the automatic locking
mode using the control system
(page 174).
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 cannot be locked or un-
locked with the central locking switch.
iThe doors unlock automatically after an
accident if the force of the impact ex-
ceeds a preset threshold.
The vehicle automatically locks when
the ignition is switched on and the
wheels are turning at vehicle speeds of
approximately 9 mph (15 km/h) or
more. You could therefore lock yourself
out when the vehicle
is pushed or towed
is on a test stand
Warning!
G
When leaving the vehicle, always remove the
SmartKey or the SmartKey with
KEYLESS-GO* 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. Unsu-
pervised use of vehicle equipment may
cause an accident and/or serious personal
injury.
Page 131 of 521
130 Controls in detailLocking and unlockingThe switch is located in the center console.Central locking switch1Locking
2UnlockingLocking
Press lower half 1 of the central lock-
ing switch.
If all doors are closed, the vehicle
locks.
Unlocking
Press upper half2 of the central lock-
ing switch.
The vehicle unlocks.
iYou can open a locked door from the
inside. Open door only when conditions
are safe to do so.
If the vehicle was previously centrally
locked using the SmartKey, it will not
unlock using the central locking switch.
If the vehicle was previously locked
with the central locking switch.
while in the selective remote con-
trol mode, only the front door
opened from the inside is unlocked.
while in the global remote control
mode, the vehicle is unlocked com-
pletely when a front door is opened
from the inside.
Page 132 of 521

131 Controls in detailSeats
Seats
For more information on seat adjustment,
see the “Getting started” section
(page 41).
Front seat active head restraints
You cannot remove the active head re-
straint on the driver’s and passenger’s
seats.For removal of the active head restraints
we recommend that you contact an autho-
rized Mercedes-Benz Center.
For information on head restraint adjust-
ment, see “Seats” (
page 42).
For information on active head restraints,
see “Active head restraints” (
page 77).
Rear seat head restraints
Folding head restraints back with
switch in the center console
The rear seat head restraints can be folded
backward for increased visibility.
1Head restraint release switch
Switch on the ignition (
page 36).
Warning!
G
For your protection, drive only with properly
positioned head restraints.
Adjust head restraint so that the center of
the head restraint supports the back of the
head at eye level. This will reduce the poten-
tial for injury to the head and neck in the
event of an accident or similar situation.
Do not drive the vehicle without the seat
head restraints. Head restraints are intend-
ed to help reduce injuries during an acci-
dent.
iAdjust the head restraint in such a way
that it is as close to the head as possi-
ble.
iThe rear seat head restraints cannot be
adjusted.
Page 133 of 521

132 Controls in detailSeats
Press the symbol-side on switch1to
release the head restraints.
The head restraints will fold backward.Placing head restraints upright
Pull the head restraint forward until it
locks into position.Removing and installing rear seat head
restraints
Warning!
G
For safety reasons, always drive with the
rear head restraints in the upright position
when the rear seats are occupied.
Keep the area around head restraints clear
of articles (e.g. clothing) to not obstruct the
folding operation of the head restraints.
!Make sure the head restraints engage
when placing them upright. Otherwise
their protective function cannot be as-
sured.
Warning!
G
For your protection, drive only with properly
positioned head restraints.
Adjust head restraint so that the head re-
straint supports the back of the head at eye
level. This will reduce the potential for injury
to the head and neck in the event of an ac-
cident or similar situation.
Do not drive the vehicle without the seat
head restraints. Head restraints are intend-
ed to help reduce injuries during an acci-
dent.
Do not interchange head restraints from
front and rear seat.
Page 134 of 521
133 Controls in detailSeats
1Release catch
Removing rear seat head restraints
Fold the backrest forward
(page 271).
Fold back head restraint (
page 131).
Press head restraint release catch1
and pull the head restraints out of the
guides.
Fold the backrest back to its original
position.Installing rear seat head restraints
Lumbar support
The curvature of the driver’s seat can be
adjusted to help enhance lower back sup-
port and seating comfort.
1Adjustment lever
Move adjustment lever1 in direction
of the arrows until you have reached a
comfortable seating position.
iWhen installing the head restraints,
make sure that:
you place the correct head restraint
on the middle seat. It is marked
with the letter “M” on the outside of
the metal bars.
the head restraints engage fully.
Page 135 of 521

134 Controls in detailSeatsDrive - Dynamic seat* with multicon-tour features
The Drive - Dynamic seat automatically ad-
justs the lateral support provided by the
backrest to your driving style.
The Drive - Dynamic seat electronically
controls the air pressure in the air cham-
bers of the backrest side bolsters. This
function improves driving comfort and
pleasure.
In addition, the Drive-Dynamic seat has a
movable seat cushion and inflatable air
cushions built into the backrest to provide
additional lumbar and side support.
The seat cushion movement, backrest
cushion height and curvature can be con-
tinuously varied with switches on the right
side of the seat on the driver side, or the
left side of the seat on the passenger side
after turning the SmartKey in the starter
switch to position2 or pressing the KEY-
LESS-GO* start/stop button twice.1Backrest center
2Backrest bottom
3Seat cushion depth
4Activate drive dynamic function
5Backrest side bolsters
6Massage function
Switch on the ignition (
page 36).Multicontour features
Seat cushion depth
Adjust the seat cushion depth to the
length of your upper leg using
switch3.
Backrest contour
Move the backrest support to the bot-
tom by using button2 or to the center
by using button1.
Adjust the contour of the backrest to
the desired position using æ or
ç.
Backrest side bolsters
Adjust the side bolsters so that they
provide good lateral support using
switch5.
Page 136 of 521

135 Controls in detailSeats
Drive-dynamic features
Activating
Press button4 (
page 134).
The indicator lamp on the button
comes on and the following display ap-
pears in the multifunction display for
about 5 seconds.
Deactivating
Press button4 (
page 134) again.
The indicator lamp on the button goes
out.Massage function (PULSE)
The massage function can help prevent
muscle tension during long drives.
Press button6 (
page 134).
The indicator lamp on the button
comes on. The air cushions in the lum-
bar area pulsate.
Seat heating*
Both switches for the front seats are locat-
ed in the center console. The red indicator
lamps in the switch come on to show
which heating level you have selected:
iYou can adjust the characteristics of
the Drive - Dynamic seat using the con-
trol system (
page 177).
iWhen the engine is turned off, the last
cushion setting is retained in memory.
The cushion is automatically adjusted
to this setting when the engine is re-
started.iThe massage function turns off auto-
matically after approximately
5 minutes.
Level3
Three indicator lamps on
(highest level)
The seat heating automatically
switches to level2 after approxi-
mately 5 minutes.
2
Two indicator lamps on
The seat heating automatically
switches to level1 after approxi-
mately 10 minutes.
1
One indicator lamp on
(lowest level)
The seat heating automatically
switches off after approximately
20 minutes.
off
No indicator lamp on