2004 MERCEDES-BENZ C240 4MATIC door locks

82 Controls in detailLocking and unlocking
In the “Controls in detail” section you will
find detailed information on how to oper-
ate the equipment installed on your vehi-
cle. 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.
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 different color to help
distinguish each SmartKey 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


the fuel filler flap
SmartKey with remote control1‹ Lock button
2Š Opening button for the trunk lid
3Mechanical key locking tab
4ΠUnlock button
5Battery check lamp
6Â Panic button* (
page 71).
iYou can also open and close the power
windows (
page 202) and
sliding/pop-up roof* (
page 204)
from outside using the SmartKey.
iCanada only:
Only vehicles equipped with an
anti-theft alarm system* have
SmartKeys with integrated panic
button*6.

83 Controls in detail
Locking and unlocking
Factory setting
Global unlocking
Press buttonŒ.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The vehicle will lock again automatically
within approximately 40 seconds of
unlocking 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‹.
All turn signal lamps flash three times.
The locking knobs in the doors move
down.
Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey so that
pressingŒ only unlocks the driver’s
door and the fuel filler flap.

Press and hold buttonsŒ and‹
simultaneously for about five seconds
until battery check lamp5 flashes
twice.
The SmartKey will then function as
follows:
Unlocking driver’s door and fuel filler
flap
Press buttonΠonce.Global unlocking

Press buttonΠtwice.
Global locking

Press button‹.
Restoring to factory setting

Press and hold buttonsŒ and‹
simultaneously for about six seconds
until battery check lamp5 flashes
twice.
!To prevent possible malfunction, avoid
exposing the SmartKey to high levels of
electromagnetic radiation.
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.

84 Controls in detailLocking and unlocking
Checking the batteries
Press button‹ orŒ.
Battery check lamp5 comes on
briefly to indicate that the SmartKey
batteries are in order.Unlocking and opening the trunk lid
You can unlock and open the trunk
separately.
A minimum height clearance of 5.71 ft
(1.74 m) is required to open the trunk lid.

Press buttonŠ until trunk unlocks
and begins to open.
The trunk can also be opened from its
inside in an emergency, see “Trunk lid
emergency release” (
page 88).
!If you can no longer lock or unlock the
vehicle with the SmartKey, then either
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 (
page 84) and replace
them if necessary (
page 307).
or


Use the mechanical key to unlock
the doors (
page 305) and the
trunk lid (
page 306) as required.
or


Use the mechanical key to lock the
doors (
page 306) and the trunk
lid (
page 306) as required.
or


Have the vehicle battery and the
battery connections checked.
If the SmartKey is malfunctioning,
contact an authorized Mercedes-Benz
Center.!If battery check lamp5 does not
come on briefly during check, then the
SmartKey batteries are discharged.
Replace the batteries (
page 307).
You can obtain the required batteries
at any authorized Mercedes-Benz
Center.
iIf the batteries are checked within
signal range of the vehicle, pressing
the‹ orŒ button will lock or
unlock the vehicle accordingly. !The trunk lid swings open upwards
automatically. Always make sure there
is sufficient overhead clearance.

90 Controls in detailLocking and unlockingSeparately unlocking the trunk
Pull the mechanical key out of the
SmartKey (
page 305).

Insert the mechanical key in the trunk
lid lock.

Turn the mechanical key
counterclockwise to neutral
position1 (
page 89).
You can now open the trunk (
page 86).
A minimum height clearance of 5.71 ft
(1.74 m) is required to open the trunk lid.
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 see “Towing the vehicle”
(
page 328).
You can deactivate the automatic locking
mode using the control system, see “Set-
ting automatic locking” (
page 133).
iYou can only cancel the separate trunk
locking mode by means of the mechan-
ical key.
Warning!
G
Only drive with the trunk closed. Among
other dangers, such as your view being
blocked, exhaust fumes may enter the
vehicle interior.
iThe doors unlock automatically after an
accident if the force of the impact
exceeds 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

91 Controls in detail
Locking and unlocking
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
y o u w a n t t o l o c k t h e v e h i c l e b e f o r e s t a r t i n g
to drive.
The fuel filler flap will not be locked or
unlocked with the central locking switch.The switch is located in the center console.
Central locking switch1Locking
2Unlocking
Locking
Press upper switch position1 of
central locking switch.
If all doors are closed, the vehicle
locks.Unlocking

Press lower switch position2 of
central locking switch.
The vehicle unlocks.
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.
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 door opened
from the inside is unlocked.


while in the global remote control
mode, the complete vehicle is
unlocked when a door is opened
from the inside.