battery MERCEDES-BENZ C-Class 2011 W204 Owner's Guide

! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged.Display messagesPossible causes/consequences and M Solutions?The engine fan is faulty.XAt coolant temperatures below 248 ‡ (120 †), continue driving
to the next qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-start driving.#The battery is not being charged.
Possible causes are:
R a faulty alternator
R a torn poly-V-belt
R a malfunction in the electronicsXPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is OK:
XVisit a qualified specialist workshop.4
Check Engine Oil
At Next
Refueling Check
Engine Oil at Next
RefuelingThe engine oil level has dropped to a critical level.
A warning tone also sounds.XCheck the oil level ( Y page 239).XIf necessary, add the engine oil ( Y page 240).XHave the engine checked for leaks if engine oil has to be added
more often than usual.
Information on approved engine oils can be obtained from any qualified specialist workshop
or on the Internet at http://www.mbusa.com (USA only).
! The oil level is too low. Avoid long journeys with too little engine oil. There is a risk of
engine damage.
The display messages and the corresponding symbol that indicate that the oil level is too
low must not be ignored.
196Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M Solutions+
Obtain a new keyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.+
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 74).+
Don't Forget Your
KeyThe display message is displayed for a maximum of 60 seconds
and is just a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XTake the KEYLESS-GO key with you when leaving the vehicle.+
Key Not Detected
(red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.+
Key Not Detected
(white display
message)The KEYLESS-GO key cannot be detected at present.XChange the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
XChange the location of the key with the KEYLESS-GO functions
in the vehicle.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.202Display messagesOn-board computer and displays
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Cigarette lighterGWarning
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
Rinjure themselves on parts of the vehicle
Rbe seriously or fatally injured through
excessive exposure to extreme heat or cold
Rinjure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
GWarning
Never touch the heating element or sides of
the lighter; they are extremely hot. Hold the
knob only.
Make sure any children traveling with you do
not injure themselves or start a fire with the
hot cigarette lighter.
Center console, front
XTurn the key to position 2 in the ignition
lock.
XSlide cover : forwards until it engages.XPress in cigarette lighter ;.
Cigarette lighter ; will pop out
automatically when the heating element is
red-hot.
12 V sockets
Points to observe before use
! If you are using all sockets in the vehicle,
make sure that you do not exceed the
maximum current draw of 55 A. Otherwise,
you will overload the fuses.
The socket can be used for accessories with
a maximum power consumption of 180 W,
e.g. lamps or chargers for mobile phones.
If you use the socket for long periods when
the engine is switched off, the battery may
discharge.
Dashboard socket
The socket is installed in vehicles with audio
equipment or COMAND.
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phone network, a valid SIM card and a
service subscription to a surveillance
service provider.
R the battery is sufficiently charged.
R the corresponding cellular phone network
is available for transmitting data to the
customer center.
i Determining the location of the vehicle on
a map is only possible if there is sufficient
GPS reception and the vehicle position can
be forwarded to the customer center.
The mbrace system
The mbrace system provides three different
services:
R automatic and manual emergency call
R Roadside Assistance call
R MB info call
To control the volume during an mbrace call,
proceed as follows:
XPress the W or X button on the
multifunction steering wheel.
or
XUse the volume controller of the audio
system.
You can find information and a description of
all available features under "Owners Online"
at http://www.mbusa.com 27
System self-test
After you have switched on the ignition, the
system carries out a self-diagnosis.
GWarning
A malfunction in the system has been
detected if any or all of the following
conditions occur:
R The indicator lamp in the SOS button does
not come on during the system self-test.
R The indicator lamp in Roadside Assistance
button F does not come on during the
system self-test.
R The indicator lamp in Information button
ï does not come on during the system
self-test.
R The indicator lamp in the SOS button,
Roadside Assistance button F, or
Information button ï remains
illuminated constantly in red after the
system self-test.
R The message Tele Aid Inoperative or
Tele Aid Not Activated appears in the
multifunction display after the system self-
test.
If a malfunction is indicated as outlined above,
the system may not operate as expected. In
case of an emergency, help will have to be
summoned by other means.
Have the system checked at the nearest
authorized Mercedes-Benz Center or contact
the following service hotlines:
R USA: Response Center under the number
866-990-9007
R Canada: Customer Service under
1-888-923-8367.
Emergency call
Important safety notes
! A license agreement must exist in order
to activate the mbrace service. Make sure
that your system is activated and ready for
use, and press the ï MB info call button
to register. If you cannot carry out any of
the steps mentioned, the system may not
be activated.
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You can obtain further information at an
authorized Mercedes-Benz Center.
The service interval display does not take into
account any periods of time during which the
battery is disconnected.
Maintaining the time-dependent service
schedule:XBefore disconnecting the battery, call up
the service due date in the multifunction
display and note it down.
or
XSubtract the battery disconnection periods
from the service date shown on the display
after reconnecting the battery.
Hiding the service message
XPress % or a on the steering wheel.
Displaying the service message
XSwitch on the ignition.XPress = or ; to select the Service
menu on the steering wheel.XPress 9 or : to select the ASSYST
PLUS submenu and press a to confirm.
The service due date appears in the
multifunction display.
Points to remember
A qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, will reset
the service interval display after the
necessary service work has been carried out.
You can obtain more information, e.g. on
maintenance work, at an authorized
Mercedes-Benz Center or directly at
Mercedes-Benz.
! If the service interval indicator has been
inadvertently reset, this setting can be
corrected at an authorized Mercedes-Benz
Center.
Have the service work carried out as
described in the Service Booklet. There
may otherwise be increased wear, resulting
in damage to the vehicle or to the major
assemblies.
Care
Notes on care
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents
recommended and approved by Mercedes-
Benz.
GWarning
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the
particular 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.
Always lock away cleaning products and keep
them out of reach of children.
! For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
HEnvironmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible
manner.
! Do not park the vehicle for an extended
period right after cleaning it, particularly
after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
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brake pads/linings. Generally, park the
vehicle at operating temperature after
cleaning.
Exterior care
Automatic car wash
GWarning!
Braking efficiency is reduced after washing
the vehicle. This could cause an accident. For
this reason, you must drive particularly
carefully after washing the vehicle until the
brakes have dried.
You can wash the vehicle in an automatic car
wash from the very start.
! Never clean your vehicle in a Touchless
Automatic Car Wash as these use special
cleaning agents. These cleaning agents can
damage the paintwork or plastic parts.
If the vehicle is very dirty, pre-wash it before
cleaning it in an automatic car wash.
! In car washes with a towing mechanism,
make sure that the automatic transmission
is in transmission position N, otherwise the
vehicle could be damaged.
! Make sure that the side windows are
completely closed, that the ventilation/
heating is switched off and that the
windshield wiper switch is set to 0.
Otherwise, the rain/light sensor could be
activated, triggering unintended wiper
movements. This can cause damage to the
vehicle.
After using an automatic car wash, wipe off
wax from the windshield and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the
windshield.
Washing by hand
Carefully remove all deposits of road salt as
soon as possible when driving in winter.
Also, clean the insides of the wheels when
washing the underbody of the vehicle.XDo not use hot water and do not wash the
vehicle in direct sunlight.XUse a soft car sponge for cleaning.XUse a gentle cleaning agent, e.g. a
Mercedes-Benz approved car shampoo.XWash down the vehicle with a gentle water
jet.XDo not point the water jet directly at the air
inlets.XUse plenty of water and rinse the sponge
frequently.XRinse the vehicle with clean water and dry
it thoroughly with a chamois.XDo not allow the cleaning agent to dry on
the paintwork.
Power washers
GWarning!
Do not use power washers with circular-jet
nozzles (dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident.
! Keep the distance between the vehicle
and the nozzle of the power washer at
11.8 in (30 cm). Information about the
correct distance is available from the
equipment manufacturer.
Move the power washer nozzle around
when cleaning your vehicle.
Do not aim directly at any of the following:
R tires
R door joint
R electrical components
R battery
R connectors
R lights
R seals
R trim elements
R ventilation slots
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Vehicle equipment ............................252
After an accident .............................. 253
Where will I find...? ...........................253
Flat tire .............................................. 254
Battery ............................................... 259
Jump-starting .................................... 262
Towing and tow-starting ..................264
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monitor cannot function reliably. Only
restart the tire pressure loss warning
system/tire pressure monitor when the
defective wheel has been replaced with a
new wheel.
Vehicles with tire pressure monitor: all
mounted wheels must be equipped with
functioning sensors and the defective
wheel should no longer be in the vehicle.
MOExtended run-flat system
The MOExtended run-flat system allows you
to drive on even if there is a complete loss of
pressure in one or more tires.
The MOExtended run-flat system may only be
used in conjunction with the activated tire
pressure loss warning system or with the
activated tire pressure monitor.
The maximum permissible distance which
can be driven in run-flat mode depends on the
cargo in the vehicle. You can drive 50 miles
(80 km) if the vehicle is partially laden and
18 miles (30 km) if it is fully laden.
The maximum permissible distance which
can be driven in run-flat mode is counted from
the moment the tire pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
50 mph(80 km/h).
GWarning!
The handling characteristics of your vehicle
deteriorate in run-flat mode, for example:
R when cornering
R when braking
R when accelerating rapidly
Adapt your driving style accordingly and avoid
sudden changes in direction and sudden
acceleration, as well as driving over obstacles
(i.e. curbs, potholes), and driving off-road.
This is particularly the case when the vehicle
is heavily laden.
The maximum permissible distance that can
be driven in run-flat mode depends to a large
extent on the loads placed on the vehicle. It
can be shorter due to high speeds, a heavy
cargo, sudden changes in direction, the road
surface condition, outside temperature, etc.,
or further if you drive carefully and
conservatively.
Do not continue to drive in run-flat mode if:
R you hear banging noises.
R the vehicle starts to shake.
R you see smoke and smell rubber.
R ESP ®
is intervening constantly.
R there are tears in the sidewalls of the tire.
After driving in run-flat mode, you must have
the wheel(s) checked for damage at a
qualified specialist workshop which has the
necessary specialist knowledge and tools to
carry out the work required. The faulty tire
must be replaced in every case.
Mercedes-Benz recommends that you use an
authorized Mercedes-Benz Center for this
purpose. In particular, work relevant to safety
or on safety-related systems must be carried
out at a qualified specialist workshop.
i When replacing one or all tires, make sure
that you only use tires marked
MOExtended and of the specified size for
the vehicle.
Battery
Important safety notes
In order for the battery to achieve the
maximum possible service life, it must always
be sufficiently charged.
! Have the battery checked regularly at a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
Observe the service intervals in the Service
Booklet or for further information consult a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
Have the battery charge checked more
frequently if you use the vehicle mainly for
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short trips or if you leave it standing idle for
a lengthy period.
To prevent damage from corrosion, only
replace the battery with one that has a central
ventilation cover.
Only replace a battery with a battery that has
been recommended by Mercedes-Benz.
Consult an authorized Mercedes-Benz Center
if you wish to leave your vehicle parked up for
a long period of time.
GWarning
Comply with safety precautions and take
protective measures when handling batteries.
Risk of explosionFire, naked flames and
smoking are prohibited
when handling the battery.
Avoid creating sparks.
Battery acid is caustic.
Avoid contact with the skin,
eyes or clothing.
Wear suitable protective
clothing, in particular
gloves, an apron and a face
mask.
Immediately rinse acid
splashes off with clean
water. Consult a doctor if
necessary.
Wear eye protection.Keep children away.Observe this Operator's
Manual.
HEnvironmental note
Do not dispose of batteries in the household
rubbish. Dispose of defective batteries in an
environmentally responsible manner. Take
them to an authorized Mercedes-Benz Center
or to a special collection point for old
batteries.
GWarning
Failure to follow these instructions can result
in severe injury or death.
Never lean over batteries while connecting.
You might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
GWarning
Do not place any metal objects on the battery
as this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First, touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! Switch off the engine and remove the key
before disconnecting the terminal clamps
from the battery. On vehicles with
KEYLESS-GO, make sure that the ignition is
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switched off. Check that all the indicator
lamps in the instrument cluster are off. You
may otherwise destroy electronic
components, such as the alternator.
! Like other batteries, the vehicle battery
may discharge over time if you do not use
the vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center. You can also charge the
battery with a charger recommended by
Mercedes-Benz. Contact an authorized
Mercedes-Benz Center for further
information.
The battery, breather hose and cover of the
positive terminal clamp must be installed
securely during operation.
i Remove the key if you park the vehicle
and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing, charging or replacing. Always have
this work performed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
i If the power supply has been interrupted,
e.g. if the battery has been reconnected,
you must carry out the following tasks:
R set the clock ( Y page 179).
R reset the function for automatically
folding the exterior mirrors in/out by
folding the mirrors out once
( Y page 100).
Charging the battery
GWarning
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and cause explosions that may
result in paint damage, corrosion or personal
injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge the battery in accordance with the
separate instructions for the accessory
battery charger.GWarning!
There is a risk of acid burns during the
charging process due to the gases which
escape from the battery. Do not lean over the
battery during the charging process.
GWarning!
Battery acid is caustic. Avoid contact with the
skin, eyes or clothing.
! Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery
chargers allow the battery to be charged
while still installed.
! Only use battery chargers with a
maximum charging voltage of 14.8 V.
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment ( Y page 262).
XOpen the hood ( Y page 238).XConnect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure
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