2010 MERCEDES-BENZ C300 4MATIC page 88

XTurn mechanical key ; back and remove
it from the trunk lid lock.
Locking the vehicle
If you cannot lock the vehicle with the
SmartKey or with KEYLESS-GO, lock it as
follows:
XOpen the driver’s door.XClose the front passenger door, the rear
doors, and the trunk.
XPress the central locking switch
(Y page 75).
The locking knobs of the front passenger
door and the rear doors move down.
XIf the vehicle battery is disconnected or
drained: Press down the locking knobs on
the front passenger door and the rear
doors.
XExit the vehicle.XClose the driver’s door.XRemove mechanical key ; from the
SmartKey (Y page 309).
XInsert mechanical key ; into the driver’s
door lock.
XTurn mechanical key ; clockwise to
position 1.
The vehicle is locked.
XTurn mechanical key ; back and remove
it from the driver’s door lock.
XCheck whether the doors and the trunk are
locked.
XIf necessary, lock the trunk with the
mechanical key (Y page 77).
iThis procedure does not arm the anti-
theft alarm system, nor does it lock the fuel
filler flap.
Fuel filler flap
GWarning!
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap.
In case the central locking system does not
release the fuel filler flap, you can open it
manually.
The fuel filler flap release is located on the
passenger side in the trunk behind the cover.
XOpen the trunk (Y page 75).XOpen the fuse box cover in the trunk
(Y page 329).
XPull fuel filler flap release : in direction of
arrow.
The fuel filler flap is unlocked.
XOpen the fuel filler flap (Y page 222).XClose the cover.XClose the trunk.310Unlocking/locking manuallyPractical hints
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XFold the head restraint cushion by the top,
back firmly until it engages :.
XRepeat this procedure on the NECK-PRO
active front head restraint for the second
front seat.
For information on NECK-PRO active front
head restraints, see “NECK-PRO active front
head restraints” (Y page 52).
For information on head restraint adjustment,
see “Seats” (Y page 79).
Replacing SmartKey batteries
If the batteries in the SmartKey are
discharged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an authorized
Mercedes-Benz Center.
GWarning!
Batteries contain poisonous and corrosive
substances. Therefore, keep the batteries out
of reach of children.
If a battery is swallowed, seek medical help
immediately.
GWarning!
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government’s disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Batteries contain materials that can harm the
environment if disposed of improperly.
Recycling of batteries is the preferred method
of disposal. Many states (USA only) or
provinces (Canada only) require sellers of
batteries to accept old batteries for recycling.
When inserting the batteries, make sure they
are clean and free of lint.
When replacing batteries, always replace
both batteries.
iThe required replacement batteries are
available at any authorized Mercedes-Benz
Center.
Replacement batteries: Lithium, type
CR 2025 or equivalent.
XRemove the mechanical key from the
SmartKey (Y page 309).
XPress mechanical key ; into the SmartKey
opening until battery compartment
cover : opens. Do not keep the cover
shut.
XRemove the battery compartment cover.XPat the SmartKey against the palm of your
hand until battery = falls out.
XInsert the new battery with the positive
terminal (+) facing up. Use a lint-free cloth.
XInsert the tabs of the battery compartment
cover into the housing and press the cover
closed.
XCheck the operation of the SmartKey as
well as the KEYLESS-GO function.
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GObserve Safety notes, see page 313.
ROnly use 12-volt bulbs of the same type and
with the specified watt rating.
RSwitch the lights off before changing a bulb
to prevent short circuits.
RAlways use a clean lint-free cloth when
handling bulbs.
RYour hands should be dry and free of oil and
grease.
RIf the newly installed bulb does not come
on, contact an authorized Mercedes-Benz
Center.
iMercedes-Benz recommends using
Longlife (LL) bulbs.
Replacing bulbs for front lamps
XSwitch off the ignition.XTurn the exterior lamp switch to position
$.
XOpen the hood (Y page 224).GWarning!
Do not remove the cover for the Bi-Xenon
headlamp. Because of high voltage in Xenon
lamps, it is dangerous to replace the bulb or
repair the lamp and its components. It is
recommended to have such work done by a
qualified technician.
Low-beam bulb (halogen headlamps
only)
XTurn housing cover : counterclockwise
and remove it.
XPull electric plug ; off the bulb ?.XRemove wire clip = from bulb holder by
pushing down and release from arrestor
hook.
XPull bulb ? at its socket out of bulb holder.XInsert the new bulb so that its socket
locates in the recess of bulb holder and is
level to it.
XFold wire clip = back and press it down on
bulb holder to engage it in the arrestor
hook.
XConnect electric plug ; on bulb ?.XAlign housing cover and turn it clockwise.
Front turn signal lamp bulb
XTurn bulb socket = with handle ;
counterclockwise and remove it.
XPull bulb out of bulb socket =.XGently press the new bulb into bulb socket
= until the bulb engages.
XPlace bulb socket = back into the housing.
Handle ; must be in a horizontal line and
mark : must be on the upper part (driver’s
side headlamp) or lower part (passenger-
side headlamp).
XTurn bulb socket = clockwise until it
engages.
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Replacing bulbs for rear lamps
Before you start to replace a bulb for a rear
lamp, do the following:
XSwitch off the ignition.XTurn the exterior lamp switch to position
$.
XOpen the trunk.
Tail lamp unit
XDriver’s side: Lift up the bottom and pull out
the trim panel covering the driver side rear
light.
XPassenger side: Open the fuse box in the
trunk (Y page 329).
XDisconnect electrical connector ;.XPull tabs : in direction of arrows.XRemove the bulb carrier.
Bulb carrier
=Side marker lamp?Rear fog lamp (driver’s side only), side
marker lamp
ABackup lampBTail lamp, brake lampCTail lamp, brake lamp, parking and
standing lamp
DTurn signal lamp
Side marker lamp
XTurn the bulb socket on backside of tail
lamp unit counterclockwise and remove
side marker lamp = with bulb socket.
XTurn the new bulb with socket on backside
of tail lamp unit clockwise until it engages.
Other lamps
XDepending on which bulb needs to be
replaced, press gently onto the respective
bulb and turn it counterclockwise out of its
bulb socket.
XGently press the new bulb into its bulb
socket and turn it clockwise until it
engages.
Reinstall bulb carrier
XReinstall the bulb carrier and let tabs :
(Y page 316) engage.
XConnect the electrical connector ;
(Y page 316) until it engages.
XReinstall trim panel.
Replacing wiper blades
Safety notes
GWarning!
For safety reasons, switch off the wipers and
remove the SmartKey from the starter switch
(vehicles with KEYLESS-GO: Make sure the
vehicle’s on-board electronics have status 0)
before replacing a wiper blade. Otherwise, the
wiper motor could suddenly turn on and cause
injury.
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GWarning!
Wiper blades are components that are subject
to wear and tear. Replace the wiper blades
twice a year, preferably in the spring and fall.
Otherwise the windshield will not be wiped
properly. As a result, you may not be able to
observe surrounding traffic conditions and
could cause an accident.
! Never open the hood when a wiper arm is
folded forward.
Hold on to the wiper when folding a wiper
arm back. If released, the force of the
impact from the tensioning spring could
crack the windshield.
Do not allow a wiper arm to contact the
windshield glass without a wiper blade
inserted.
Mercedes-Benz recommends that you have
this work carried out at an authorized
Mercedes-Benz Center.
XRemove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO:
XMake sure the vehicle’s on-board
electronics have status 0 (Y page 78).
Removing wiper blades
! Do not pull on the wiper blade inserts.
They could tear.
XFold the wiper arm forward until it snaps
into place.
XTurn the wiper blade in direction of
arrow :.
XSlide the wiper blade sideways out of the
retainer in the direction of arrow ;.
Installing wiper blades
XSlide the wiper blade onto the wiper arm
until it locks in place.
XRotate the wiper blade into a position
parallel to the wiper arm.
XFold the wiper arm backward to rest on the
windshield.
Make sure you hold on to the wiper when
folding the wiper arm back.
! Make sure the wiper blades are installed
properly. Improperly installed wiper blades
may cause windshield damage.
Flat tire
Safety notes
GWarning!
The dimensions of the spare wheel are
different from those of the road wheels. As a
result, the vehicle handling characteristics
change when driving with a spare wheel
mounted. Adapt your driving style
accordingly.
The spare wheel is for temporary use only.
When driving with a spare wheel mounted,
ensure proper tire inflation pressure and do
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not exceed a vehicle speed of 50 mph
(80 km/h).
Contact the nearest authorized Mercedes-
Benz Center as soon as possible to have the
spare wheel replaced with a regular road
wheel.
Never operate the vehicle with more than one
spare wheel mounted.
Do not switch off the ESP ®
when a spare
wheel is mounted.
Preparing the vehicle
XWhenever possible, park the vehicle in a
safe distance from moving traffic on a hard,
flat surface.XTurn on the hazard warning flasher.XTurn the steering wheel so that the front
wheels are in a straight-ahead position.XEngage the parking brake.XShift the automatic transmission into park
position P (manual transmission to 1st or
reverse gear R).XTurn off the engine.XRemove the SmartKey from the starter
switch.
or
XVehicles with KEYLESS-GO: Open the
driver’s door (this puts the starter switch in
position 0, same as with the SmartKey
removed from the starter switch). The
driver’s door can then be closed again.
Open doors only when conditions are safe
to do so.XVehicles with KEYLESS-GO: Remove the
KEYLESS-GO start/stop button from the
starter switch.XHave any passenger exit the vehicle at a
safe distance from the roadway. Open
doors only when conditions are safe to do
so.Mounting the spare wheel
IntroductionXPrepare the vehicle as described
( Y page 318).XTake the following out of the vehicle:
R spare wheel
R jack
R vehicle tool kit box
For information on where to find the
respective items, see “Where will I find ...?”
( Y page 268) and ( Y page 270).
i Vehicles without spare wheel are not
factory-equipped with the tools required for
a wheel change such as a jack or a wheel
wrench. Some tools required for a wheel
change are specific to your vehicle.
Contact an authorized Mercedes-Benz
Center to obtain the tools approved for
your vehicle. This section describes the
wheel change using the tools approved and
recommended for your vehicle.
Lifting the vehicle
GWarning!
When jacking up the vehicle, only use the jack
which has been specifically approved by
Mercedes-Benz for your vehicle.
The jack is designed exclusively for jacking up
the vehicle at the jack take-up brackets built
into both sides of the vehicle. Make sure the
jack arm is fully seated in the jack take-up
bracket. The jack must always be vertical
when in use, especially on inclines or
declines.
The jack is intended only for lifting the vehicle
briefly for wheel changes. It is not suited for
performing maintenance work under the
vehicle. To help avoid personal injury, use the
jack only to lift the vehicle during a wheel
change.
Never get beneath the vehicle while it is
supported by the jack. Keep hands and feet
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away from the area under the lifted vehicle.
Always lower the vehicle onto sufficient
capacity jackstands before working under the
vehicle.
Always engage the parking brake firmly and
block the wheels with wheel chocks or other
sizeable objects before raising the vehicle
with the jack. Do not disengage the parking
brake while the vehicle is raised.
Make sure that the ground on which the
vehicle is standing and where you place the
jack is solid, level and not slippery. If
necessary, use a large underlay. On slippery
surfaces, such as tiled floors, you should use
a non-slip underlay, for example a rubber mat.
Do not use wooden blocks or similar objects
to support the jack. Otherwise the jack may
not be able to achieve its load-bearing
capacity if it is not at its full height.
Never start the engine when the vehicle is
raised.
Also observe the notes on the jack.
XPrevent the vehicle from rolling away by
blocking wheels with wheel chocks or other
sizeable objects.
When your vehicle is equipped with a wheel
chock, it is included with the vehicle tool kit
(Y page 268). For information on setting up
the collapsible wheel chock, see
(Y page 269).
When changing a wheel on a level surface:
XPlace a wheel chock or other sizeable
object in front of and another wheel chock
or other sizeable object behind the wheel
that is diagonally opposite to the wheel
being changed.
Always try lifting the vehicle using the jack on
a level surface. However, should
circumstances require you to do so on a hill:
XPlace wheel chocks or other sizeable
objects on the downhill side in front of both
wheels on the side opposite to the side on
which the wheel is to be changed.
GWarning!
Only jack up the vehicle on level ground or on
slight inclines/declines. Otherwise, the
vehicle could fall off the jack and injure you or
others.
XOn the wheel to be changed, loosen but do
not yet remove the wheel bolts
(approximately one full turn with wheel
wrench :).
The jack take-up brackets are located directly
behind the front wheel housings and in front
of the rear wheel housings.
GWarning!
The jack is designed exclusively for jacking up
the vehicle at the jack take-up brackets. Make
sure the jack arm is fully seated in the jack
take-up bracket.
If you do not position the jack correctly in the
jack take-up bracket, the vehicle can fall off
the jack and seriously or fatally injure you or
others.
! Do not position the jack on the body of
the vehicle, as this may cause damage to
the vehicle.
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Lowering the vehicleXLower the vehicle by turning the crank
counterclockwise until the vehicle is
resting fully on its own weight.
XRemove the jack.XTighten the five wheel bolts evenly,
following the diagonal sequence illustrated
(: to A), until all bolts are tight. Observe
a tightening torque of 96 lb-ft (130 Nm).
GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
96 lb-ft (130 Nm).
XFully collapse the jack, with handle folded
in (storage position), see (Y page 269).
XStore the jack and the other vehicle tools
in the designated storage space.
For information on storing the spare wheel
after it has been replaced by a regular road
wheel, see (Y page 270).
iVehicles with TPMS:
Do not restart the tire inflation pressure
monitor until a full size wheel/tire with
functioning sensor has been placed back
into service on the vehicle.
Battery
Safety notes
A battery should always be sufficiently
charged in order to achieve its rated service
life. Refer to Maintenance Booklet for battery
maintenance intervals.
If you use your vehicle mostly for short-
distance trips, you will need to have the
battery charge checked more frequently.
When replacing a battery, always use a
battery approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, contact an
authorized Mercedes-Benz Center about
steps you need to observe.
GWarning!
Observe all safety instructions and
precautions when handling automotive
batteries.
Risk of explosion.Fire, open flames and
smoking are prohibited
when handling batteries.
Avoid creating sparks.
Battery acid is caustic. Do
not allow it to come into
contact with skin, eyes or
clothing.
Wear suitable protective
clothing, especially gloves,
apron and faceguard.
Wear eye protection.
Rinse any acid spills
immediately with clear
water. Contact a physician
if necessary.
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