coolant temperature MERCEDES-BENZ R-Class 2011 W251 User Guide

Display messagesPossible causes/consequences and M Solutions?The engine fan is faulty.XAt coolant temperatures under 248 ‡(120 †), drive 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.#
Battery/
Alternator Stop
VehicleThe battery is faulty.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.4
Check engine oil
level at next
refuelingThe oil level is too low.XCheck the oil level ( Y page 279).XIf necessary, add the engine oil ( Y page 280).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.
226Display messagesOn-board computer and displays
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Engine compartment
Hood
Opening the hood
GWarning
Do not pull the release lever while the vehicle
is in motion. Otherwise, the hood could be
forced open by passing air flow.
This could cause the hood to come loose and
injure you and/or others.
GWarning!
Do not open the hood when the engine is
overheated. You could be seriously injured.
Observe the coolant temperature display to
determine whether the engine may be
overheated. If you see flames or smoke
coming from the engine compartment, move
away from the vehicle. Wait until the engine
has cooled. If necessary, call the fire
department.
GWarning
There is a risk of injury if the hood is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Operator's
Manual and observe the relevant safety notes.
GWarning
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running.
The radiator fan may continue to run for
approximately 30 seconds or may even
restart after the engine has been turned off.
Stay clear of fan blades.
GWarning!
Vehicles with gasoline engine:
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components
(ignition coils, spark plug sockets, diagnostic
socket) of the ignition system
R with the engine running
R while starting the engine
R when the ignition is switched on and the
engine is turned manually
GWarning!
Vehicles with diesel engine:
The engine is equipped with a high-voltage
electronic control unit for the injection
system. Because of the high voltage it is
dangerous to touch any components of the
injection system (injectors, electrical wires)
R with the engine running
R while starting the engine
R when the ignition is switched on
XMake sure that the windshield wipers are
switched off.GWarning
The windshield wipers and wiper linkage
could be set in motion.
When the hood is open, you or others could
be injured by the wiper linkage.
Make sure that the windshield wipers are
switched off. Remove the SmartKey or make
sure that no ignition position has been
selected with KEYLESS-GO. All indicator
lamps must be off in the instrument cluster.
278Engine compartmentMaintenance and care
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Further information on engine oil
( Y page 354).XReplace cap : on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
Checking and adding other service
products
Checking the coolant level
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
XTurn the SmartKey to position
2 (Y page 149) in the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 149).XCheck the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).GWarning
In order to avoid any potentially serious burns:
R use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system, or
if the coolant temperature display indicates
that the coolant is overheated.
R do not remove the pressure cap on the
coolant reservoir if the coolant temperature
is above 158 ‡ (70 †). Allow the engine to
cool down before removing the cap. The
coolant reservoir contains hot fluid and is
under pressure.
R using a rag, slowly turn the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding
hot fluid and steam will be blown out under
pressure.
R do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.XSlowly turn cap : half a turn counter-
clockwise and allow excess pressure to
escape.XTurn 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 ;.
If the coolant is approximately 0.6 in
(1.5 cm) higher when warm, there is
enough coolant in coolant expansion
tank ;.XIf necessary, add coolant which has been
tested and approved by Mercedes-Benz.XReplace cap : and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y page 355).
Windshield washer system/headlamp
cleaning system
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
GWarning
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
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Otherwise, you may damage the engine and
the exhaust gas aftertreatment.
Mercedes-Benz recommends MOBIL OIL.
The table shows which engines oil have been
approved for your vehicle.
ModelEngine
model
MB
Approval
R 350 BlueTEC642229.51R 350272229.5
iMB Approval is stated on the containers.
Lubricant additives
! Do not mix any lubricant additives with
the engine oil. This could damage the
engine. Damage resulting from the use of
such lubricant additives in the engine oil is
not covered by the Mercedes-Benz Limited
Warranty.
Engine oil viscosity
Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity,
this means that it is thick; a low viscosity
means that it is thin.
Select the SAE classification (viscosity) of the
engine oil according to the outside
temperature. The following table shows you
the viscosity classes to be used depending on
the average air temperature.
Refrigerant of the air-conditioning
system
The air-conditioning system is filled with
R134a refrigerant and a special PAG
lubricant.
! Never use refrigerant R 12 (CFC) or
mineral lubricants. Otherwise, you could
damage the air-conditioning system.
Brake fluid
GWarning!
The brake fluid constantly absorbs moisture
from the air; this lowers its boiling point.
If the boiling point of the brake fluid is too low,
vapor pockets may form in the brake system
when the brakes are applied hard (e.g. when
driving downhill). This would impair braking
efficiency.
You should have the brake fluid renewed at
regular intervals. The brake fluid change
intervals can be found in the Service Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake
fluids can be obtained from any authorized
Mercedes-Benz Center.
Coolant
Important safety notes
The coolant is a mixture of water and
anticorrosion/antifreeze. It performs the
following tasks:
Ranti-corrosion protection
Rantifreeze protection
Rraising the boiling point
The cooling system is filled with coolant at the
factory which contains antifreeze/corrosion
inhibitor that ensures protection down to
approximately -35 ‡ (-37 †).
! Only use premixed coolant solutions.
Adding water and MB 325.0 Anticorrosion/
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Antifreeze separately from each other,
could cause engine damage not covered by
the Mercedes-Benz Limited Warranty.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the cooling system will not be
sufficiently protected from corrosion, and
the boiling point will be too low.
If the coolant has antifreeze protection down
to -35 ‡ (-37 †), the boiling point of the
coolant in the pressurized system is
approximately 266 ‡ (130 †).
The coolant must be used throughout the year
in order to maintain the necessary corrosion
protection and provide protection from
overheating. In the Service Booklet, you can
find information on the intervals for renewal.
The renewal interval is determined by the
coolant type and the cooling system design.
The renewal interval in the Service Booklet is
only valid if the coolant is added or renewed
with Mercedes-Benz approved products.
Therefore, only use MB 325.0 Anticorrosion/
Antifreeze or another Mercedes-Benz
approved product of the same specification.
Information on other Mercedes-Benz
approved products of the same specification
can be obtained at any authorized Mercedes-
Benz Center or on the Internet at
http://www.mbusa.com (USA only).
The anticorrosion/antifreeze concentration
in the cooling system should:
R be at least 50%. This will protect the cooling
system against freezing down to around
-35 ‡ (-37 †).
R not exceed 55% (antifreeze protection
down to -49 ‡ [-45 †]); otherwise, heat will
not be dissipated as effectively.
If the coolant level is too low, a mixture of
water and MB 325.0 Anticorrosion/
Antifreeze should be added. Have the cooling
system checked for leaks. Please make sure
the mixture is in accordance with label
instructions.The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water.
If you are unsure about the water quality,
contact an authorized Mercedes-Benz
Center.356Service products and capacitiesTechnical data
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Anticorrosion/antifreeze
Your vehicle has a number of aluminum components. The use of aluminum components in
motor vehicle engines necessitates that anticorrosion/antifreeze coolant used in such
engines be specifically formulated to protect the aluminum parts. Failure to use such
anticorrosion/antifreeze coolant will result in a significantly shortened service life.
For this reason, the following product is expressly recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze.
The coolant concentration should be checked before the onset of winter or once a year in
warmer regions.
The coolant is checked at every service at an authorized Mercedes-Benz Center.
ModelAntifreeze protection to approximately-35 ‡ (-37 †)-49 ‡ (-45 †)Cooling systemAll models5.0 US qt (4.75 l)5.5 US qt (5.2 l)Windshield and headlamp cleaning
system GWarning
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
XUse MB Windshield Washer Concentrate
MB SummerFit.XAt temperatures above freezing: add 1
part MB SummerFit to 100 parts water, e.g.
1.34 fl oz (40 ml) MB SummerFit to 1 gal
(4.0 l) of water.XAt temperatures below freezing: add 1
part MB SummerFit to 100 parts washer
fluid, e.g. 1.34 fl oz (40 ml) MB SummerFit
to 1 gal (4.0 l) of water.Vehicle data
Vehicle data, R 350 BlueTEC
(251.125)
The data quoted here refers specifically to a
vehicle with standard equipment. Contact an
authorized Mercedes-Benz Center for the
data for all vehicle variants and trim levels.
Vehicle dimensions, R 350 BlueTECVehicle length203.3 in (5163 mm)Vehicle width
including exterior
mirrors85.9 in (2182 mm)Vehicle height65.6 in (1666 mm) 52Wheelbase126.6 in (3215 mm)Front track64.5 in (1638 mm)Rear track64.4 in (1636 mm)Ground clearance5.9 in (150 mm)52Turning circle41.3 ft (12.6 m)52
The values apply to an unladen vehicle with standard equipment. On vehicles with the AIRMATIC package,
the values vary depending on the level set for the vehicle suspension.Vehicle data357Technical dataBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 357Z