2005 MERCEDES-BENZ C240 Fuel door

88 Controls in detailIn 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
For more information on locking and
unlocking, see “Getting started”
(page 32) and (
page 54).
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 76).
iCanada only:
Only vehicles equipped with an
anti-theft alarm system* have
SmartKeys with integrated panic
button6.

89 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 anti-theft alarm system* is
switched off.
The vehicle will lock again automatically
and reactivate the anti-theft alarm
system* 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. The anti-theft alarm system* is
activated.
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.
Warning!
G
When leaving the vehicle, always remove the
SmartKey from the starter switch and lock
the vehicle. Do not leave children unattend-
ed in the vehicle, or with access to an un-
locked vehicle. It is possible for children to
open a locked door from the inside, which
could result in an accident and/or serious
injury.!To prevent possible malfunction, avoid
exposing the SmartKey to high levels of
electromagnetic radiation.iYou can also open and close the power
windows (
page 225) and power
tilt/sliding sunroof* (
page 229) from
outside using the SmartKey.


90 Controls in detailLocking and unlocking
The SmartKey will then function as
follows:
Unlocking driver’s door and fuel filler
flap

Press buttonΠonce.
All turn signal lamps flash once. The
locking knob in the driver's door moves
up. The anti-theft alarm system* is
switched off.
Global unlocking

Press buttonΠtwice.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system* is
switched off.Global locking

Press button‹.
All turn signal lamps flash three times.
The locking knobs in the doors move
down. The anti-theft alarm system* is
activated.
Restoring to factory setting

Press and hold buttonsŒ and‹
simultaneously for about six seconds
until battery check lamp5 flashes
twice.
!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 91) and replace
them if necessary (
page 343).


Use the mechanical key to unlock
the driver’s door (
page 337) and
the trunk lid (
page 338).


Use the mechanical key to lock the
driver’s door (
page 338).


Have the vehicle battery and the
battery connections checked
(page 360).
If the SmartKey is malfunctioning,
contact an authorized Mercedes-Benz
Center.


96 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 door 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 145).
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.
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 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.

288 OperationTires and wheels
Tire pressure changes by approx. 1.5 psi
(0.1 bar) per 18°F (10°C) of air tempera-
ture change. Keep this in mind when
checking tire pressure where the tempera-
ture is different from the outside tempera-
ture.
Tire temperature and tire pressure are also
increased while driving, depending on the
driving speed and the tire load.
Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
b e c o m e w o r n o v e r t i m e e v e n i f n e v e r u s e d ,
and thus should be inspected and replaced
when necessary.
iThe pressures listed for light loads are
minimum values offering high driving
comfort.
Increased inflation pressures listed for
heavier loads may also be used for light
loads. These higher pressures produce
favorable handling characteristics. The
ride of the vehicle, however, will be
somewhat harder. Never exceed the
max. values or inflate tires below the
min. values listed in the fuel filler flap.
Warning!
G
Follow recommended inflation pressures.
Do not overinflate tires. Overinflated tires
can result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes, etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indi-
cated by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.

295 Operation
Vehicle care
Vehicle care
Cleaning and care of the vehicle
While in operation, even while parked, your
vehicle is subjected to varying external
influences which, if gone unchecked, can
attack the paintwork as well as the under-
body and cause lasting damage.Such damage is caused not only by
extreme and varying climatic conditions,
but also by:


Air pollution


Road salt


Tar


Gravel and stone chipping
To avoid paint damage, you should
immediately remove:


Grease and oil


Fuel


Coolant


Brake fluid


Bird droppings


Insects


Tree resins, etc.
Frequent washing reduces and/or elimi-
nates the aggressiveness and potency of
the above adverse influences.More frequent washings are necessary to
deal with unfavorable conditions:


near the ocean


in industrial areas (smoke, exhaust
emissions)


during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a thor-
ough check is a washing of the underbody
followed by a thorough inspection. Dam-
aged areas need to be re-undercoated.
Your vehicle has been treated at the facto-
ry with a wax-base rustproofing in the body
cavities which will last for the lifetime of
the vehicle. Post-production treatment is
neither necessary nor recommended by
Mercedes-Benz because of the possibility
of incompatibility between materials used
in the production process and others
applied later.
Warning!
G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not
designed for cleaning your vehicle.

339 Practical hints
Unlocking/locking in an emergency
1Locking
Insert the mechanical key into the
driver’s door lock until it stops.

Turn the mechanical key clockwise to
position1.
The driver’s door is locked.
Fuel filler flap
In case the central locking system does
not release the fuel filler flap, you can open
it manually.
The release button is on the right-hand
side of the luggage compartment behind
the side trim.1Side trim
2Release button

Open the trunk lid.

Remove the side trim1 from the
right-hand side of the luggage compart-
ment.

Turn release button2 clockwise as far
as will go.
The fuel filler flap is released.

Open the fuel filler flap from outside.
Warning!
G
If you operate the emergency release but-
ton, be careful of the sharp edges so that
you do not injure yourself.

401 Technical terms
Instrument cluster
The displays and indicator/warning
lamps in the driver’s field of vision,
including the tachometer, speedo-
meter, engine temperature display and
fuel gauge.
Kickdown
Depressing the accelerator past the
point of resistance shifts the transmis-
sion down to the lowest possible gear.
This very quickly accelerates the
vehicle and should not be used for
normal acceleration needs.
Lock button
Button on the door which indicates
whether the door is locked or
unlocked. Pushing the lock button
down on an individual door from inside
will lock that door.Maintenance System (U.S. vehicles)
Maintenance service indicator in the
multifunction display that informs the
driver when the next vehicle mainte-
nance service is due. The Maintenance
System in your vehicle tracks distance
driven and the time elapsed since your
last maintenance service, and calls for
the next maintenance service accord-
ingly.
Memory function*
Used to store three individual seat,
steering wheel and mirror positions for
each SmartKey.
MON
(M
otor O
ctane N
umber)
The Motor Octane Number for gasoline
as determined by a standardized
method. It is an indication of a
gasoline's ability to resist undesired
detonation (knocking). The average of
both the MON (Motor Octane Number)
and ->RON (Research Octane Number)
is posted at the pump, also known as
ANTI-KNOCK INDEX.Multifunction display
Display field in the instrument cluster
used to present information provided
by the control system.
Multifunction steering wheel
Steering wheel with buttons for
operating the control system.
Overspeed range
Engine speeds within the red marking
of the tachometer dial. Avoid this
engine speed range, as it may result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.
Poly-V-belt drive
Drives engine-components (alternator,
AC compressor, etc.) from the engine.