coolant MERCEDES-BENZ B-CLASS 2012 User Guide

Display messages Possible causes/consequences and
M Solutions?
Coolant Too Hot
Stop Vehicle Turn
Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 248 ‡ (120 †).
Otherwise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under
normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). # The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue

driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop immediately. Display messages
213
On-board computer and displays Z
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Engine
Problem Possible causes/consequences and
M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified
specialist workshop as
soon as the yellow Check Engine warning
lamp lights up. This depends on the locally applicable legal
requirements. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving. æ
The yellow reserve fuel
warning lamp lights up
while the engine is
running.
The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. æ
The yellow reserve fuel
warning lamp flashes
while the engine is
running.
The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X
Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed:
close the

fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist
workshop. ?
The red coolant
warning lamp lights up
while the engine is
running and
the

coolant
temperature gage is at
the start of the scale. The temperature sensor for the coolant temperature gage is
defective.
The coolant
temperature
is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to

road and traffic conditions. Do not continue
driving under any circumstances.
X Secure the vehicle against rolling away ( Y page 149).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
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Problem Possible causes/consequences and
M Solutions?
The red coolant
warning lamp
comes
on
while the engine is
running. The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be
malfunctioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant (Y page 269). Observe
the warning notes.
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
under

248 ‡
(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. ?
The red coolant
warning lamp
comes

on
while the engine is
running. A warning tone
also sounds. The coolant temperature has exceeded 248 ‡ (120 †). The
airflow
to the
engine radiator may be blocked or the coolant level
may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive
when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Vapor from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).232
Warning and indicator lamps in the instrument cluster
On-board computer and displays
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Problem Possible causes/consequences and
M SolutionsX
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant (Y page 269). Observe
the warning notes.
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X At
coolant temperatures under 248 ‡ (120 †),
drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. Driving systems
Problem Possible causes/consequences and
M Solutions·
The red distance
warning lamp lights up
while the vehicle is in
motion. A
warning

tone
also sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action. Warning and indicator lamps in the instrument cluster
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Checking and adding other service
products
Checking coolant level G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap,
you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
! The coolant may only be checked and
corrected when the engine is cool (coolant
temperature below 104 ‡ (40 †).
Checking the coolant when the coolant
temperature is above 104 ‡ (40 †) may
result in damage to the engine or to the
engine cooling system. Example
X
Park the vehicle on a level surface.
Only check the coolant level when the
vehicle is on

a level surface and the engine
has cooled down.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
104 ‡ (40 †).
X Turn the SmartKey to position
0 (

Y page 135) in the ignition lock. X
Slowly turn cap : half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap : further counter-clockwise
and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
X If necessary, add coolant that has been
tested and approved by Mercedes-Benz.
X Replace cap : and turn

it clockwise as far
as it will go.
For further information on coolant, see
(Y page 333).
Adding washer fluid to the windshield
washer system/headlamp cleaning
system G
WARNING
Windshield washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windshield washer
concentrate is spilled next to the filler neck. Example
X
To open: pull cap : upwards by the tab.
X Add the premixed washer fluid.
X To close:
press cap :
onto the filler neck
until it engages. Engine compartment
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Maintenance and care Z
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Cleaning the wheels
!
Do not use
acidic wheel cleaning products
to remove brake dust. This could damage
wheel bolts and brake components.
! Do not park the vehicle for an extended
period straight after cleaning it, particularly
after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
brake pads/linings. For this reason, you
should drive for a few minutes after
cleaning. Braking heats the brake discs and
the brake pads/linings, thus drying them.
The vehicle can then be parked.
Cleaning the paintwork !
Do not affix:
R stickers
R films
R magnetic plates or similar items
to painted surfaces. You could otherwise
damage the paintwork.
X Remove dirt immediately, where possible,
while avoiding rubbing too hard.
X Soak insect remains with insect remover
and rinse off the treated areas afterwards.
X Soak bird droppings with water and rinse
off the treated areas afterwards.
X Remove coolant, brake fluid, tree resin,
oils, fuels and greases by rubbing gently
with a cloth soaked in petroleum ether or
lighter fluid.
X Use tar remover to remove tar stains.
X Use silicone remover to remove wax.
X Use a suitable touch-up stick, e.g. MB
Touch-Up Stick, to repair slight damage to
the paintwork quickly and provisionally.
The following cannot always be completely
repaired:
R scratches
R corrosive deposits R
areas affected by corrosion
R damage caused by inadequate care
In such cases, visit a qualified specialist
workshop.
If water no

longer forms "beads" on the paint
surface, use the paint care products
recommended and approved by Mercedes-
Benz. This is the case approximately every
three to five months, depending on the
climate conditions and the care product used.
If the dirt has penetrated the paint surface or
if the paintwork has become dull, then the
paintwork should be cleaned. For cleaning,
please use the paint cleaner recommend and
approved by Mercedes Benz.
Do not use these care products in the sun or
on the hood while the hood is hot.
Matte finish care !
Never polish the vehicle or the light alloy
wheels. Polishing causes the finish to
shine.
! The following may cause the paint to
become shiny and thus reduce the matte
effect:
R Vigorous rubbing with unsuitable
materials.
R Frequent use of car washes.
R Washing the vehicle in direct sunlight.
! Never use paint cleaner, buffing or
polishing products, or

gloss preserver, e.g.
wax. These products are only suitable for
high-gloss surfaces. Their use on vehicles
with matte finish leads to considerable
surface damage (shiny, spotted areas).
Always have paintwork repairs carried out
at a qualified specialist workshop.
! Do not use wash programs with a hot wax
treatment under any circumstances.
Observe these notes if your vehicle has a
clear matte finish. This will help you to avoid
damage to the paintwork due to incorrect
treatment. Care
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Maintenance and care Z
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GAWR (Gross Axle Weight Rating)
The GAWR is
the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side. Speed rating
The speed rating is part of the tire
identification. It specifies

the speed range for
which the tire is approved. GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight, if
applicable. The gross

vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B-pillar on the driver's side. GVWR (Gross Vehicle Weight Rating)
The GVWR is

the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight, if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side. Maximum loaded vehicle weight
The maximum weight is the sum of:
R the curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa
corresponds to 1 psi. Another unit for tire
pressure is bar. 100 kilopascal (kPa) is the
equivalent of 1 bar . Load index
In addition to

the load-bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load-bearing
capacity more precisely. Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil

and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage. Maximum load rating
The maximum load rating in kilograms or
pounds is the maximum weight for which a
tire is approved. Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire. Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the

maximum axle load of one axle
by two. PSI (pounds per square inch)
A standard unit of measure for tire pressure. Definition of terms for tires and loading
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Wheels and tires Z
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applicable to your vehicle on the vehicle
identification plate.
VIN
X
Slide the right-hand front seat to its
rearmost position.
X Fold up floor covering : in front of the
right-hand front seat.
You will see VIN ;.
The VIN can also be found in the following
locations:
R on the lower edge of the windshield
(Y page 329)
R on the vehicle identification plate
(Y page 328) Engine number
:
Emissions control information plate
; Engine number (stamped into the
crankcase)
= VIN (on the lower edge of the windshield) Service products and filling
capacities
Important safety notes
G
WARNING
Service products may be poisonous and
hazardous to health. There is a risk of injury.
Comply with instructions on the use, storage
and disposal of
service products on the labels
of the respective original containers. Always
store service products sealed in their original
containers. Always keep service products out
of the reach of children. H
Environmental note
Dispose of service products in an
environmentally responsible manner.
Service products include the following:
R Fuels
R Lubricants (e.g. engine

oil, transmission oil)
R Coolant
R Brake fluid
R Windshield washer fluid
R Climate control system refrigerant
Components and service products must be
matched. You should therefore only use
products that have been tested and approved
by Mercedes-Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz. Service products and filling capacities
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When handling brake fluid, observe the
important safety notes on service products
(Y page 329).
The brake
fluid
change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist
workshop or on the Internet at
http://bevo.mercedes-benz.com.
i Have the brake fluid renewed regularly at
a qualified specialist workshop. Coolant
Important safety notes G
WARNING
If antifreeze comes into contact with hot
components in the engine compartment, it
may ignite. There is a risk of fire and injury.
Let the engine cool down before you add
antifreeze. Make sure that antifreeze is not
spilled next to the filler neck. Thoroughly
clean the antifreeze

from components before
starting the engine.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be
found in the Mercedes-Benz Specifications
for Service Products, MB Specifications for
Service Products 310.1, e.g. on the
Internet at
http://bevo.mercedes-benz.com. Or
contact a qualified specialist workshop.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating. When handling coolant, observe the
important safety notes on service products
(Y page 329).
The coolant is a mixture of water and
antifreeze/corrosion inhibitor. It performs
the following tasks:
R
corrosion protection
R antifreeze protection
R raising the boiling point
If the coolant

has antifreeze protection down
to -35 ‡ (-37 †), the boiling point of the
coolant during operation is approximately
266 ‡ (130 †).
The antifreeze/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †).
R not exceed 55% (antifreeze protection
down to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
If the vehicle has lost coolant, add equal
amounts of water and antifreeze/corrosion
inhibitor.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in
accordance with MB Specifications for
Service Products 310.1.
The coolant is checked with every
maintenance interval at a qualified specialist
workshop.
i When the vehicle is first delivered, it is
filled with a coolant mixture that ensures
adequate antifreeze and corrosion
protection.
Filling capacities Model Capacity
B 250
BlueEFFICIENCY
Approx. 8.2 US qt
(7.8 l) Service products and filling capacities
333
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