2015 MERCEDES-BENZ M-Class engine overheat

Problem
Possible causes/consequences and
0050
0050Solutions 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunc-
tioning.
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 182).
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, observing the warning
notes (Y page 369).
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
below 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 moun-
tainous terrain, and stop-and-go traffic. 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow 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.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury. Warning and indicator lamps in the instrument cluster
329On-board computer and displays Z

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 29). Engine compartment
Hood
Important safety notes G
WARNING
If the hood is unlatched, it may open up when the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. G
WARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement. G
WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. G
WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
R switch off the ignition
R never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
R remove jewelry and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts G
WARNING
The ignition system and the fuel injection sys- tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition is switched on.
Opening the hood G
WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following. G
WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood. 366
Engine compartmentMaintenance and care

R
Gasoline with metalliferous additives
R Diesel
Do not mix such fuels with the fuel recom-
mended for your vehicle. Do not use addi-
tives. This can otherwise lead to engine
damage. This does not include cleaning
additives for the removal and prevention of residue build-up. gasoline may only be
mixed with cleaning additives recommen-
ded by Mercedes-Benz; see "Additives".
You can obtain further information from
any authorized Mercedes-Benz Center.
! To ensure the longevity and full perform-
ance of the engine, only premium-grade
unleaded gasoline must be used.
If standard unleaded gasoline is unavaila-
ble and you have to refuel with unleaded
gasoline of a lower grade, observe the fol-
lowing precautions:
R Only fill the fuel tank to half full with reg-
ular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R Do not drive at the maximum speed.
R Avoid sudden acceleration and engine
speeds over 3,000 rpm.
Using mixtures of methanol and ethanol is not permitted. E10 fuel or E15 fuel (unleaded gas-
oline with 10% or 15% ethanol) can be used.
You will usually find information about the fuel
grade on the pump. If you cannot find the
label on the pump, ask the staff for assis-
tance.
i For further information, consult a quali-
fied specialist workshop or visit
http://www.mbusa.com (USA only).
All other models: as a temporary measure, if
the recommended fuel is not available, you
may also use regular unleaded gasoline with
an octane rating of 87 RON/91 MON. This
may reduce engine performance and increase fuel consumption. Avoid driving at full throttle
and sudden acceleration. Never refuel using
fuel with a lower AKI. Information on refueling (Y
page 178).
Additives ! Operating the engine with fuel additives
added later can lead to engine failure. Do
not mix fuel additives with fuel. This does
not include additives for the removal and
prevention of residue buildup. gasoline
must only be mixed with additives recom-
mended by Mercedes-Benz. Comply with
the instructions for use on the product
label. More information about recommen-
ded additives can be obtained from any
authorized Mercedes-Benz Center.
Mercedes-Benz recommends that you use
branded fuels that have additives.
The quality of the fuel available in some coun- tries may not be sufficient. Residue could
build up in the injection system as a result. In
such cases, and in consultation with an
authorized Mercedes-Benz Center, the gaso-
line may be mixed with the cleaning additive
recommended by Mercedes-Benz. You must
observe the notes and mixing ratios specified
on the container.
Diesel Fuel grade
G
WARNING
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline with diesel fuel.
! Refuel only using diesel fuel that con-
forms to European standard EN 590 or an
equivalent specification. Fuel that does not conform to EN 590 can lead to increased
wear and damage the engine and exhaust
system. Service products and filling capacities
449Technical data Z

!
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.
i Have the coolant regularly replaced at a
qualified specialist workshop and the
replacement confirmed in the Maintenance Booklet.
Comply with the important safety precautions
for service products when handling coolant
(Y page 447).
The coolant is a mixture of water and anti-
freeze/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 cool-
ant during operation is approximately 266 ‡
(130 †).
The antifreeze/corrosion inhibitor concentra- tion 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
do wn to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in accord-
ance with MB Specifications for Service Prod-
ucts 310.1.
i When the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures
adequate antifreeze and corrosion protec-
tion.
i The coolant is checked with every main-
tenance interval at a qualified specialist
workshop. Filling capacities Model Capacity
ML 350
ML 350 4MATIC
Approx. 11.1 US qt
(10.5 l) ML 400
ML 400 4MATIC
Approx. 10.9 US qt
(10.3 l) ML 550 4MATIC
Approx. 12.0 US qt
(11.4 l) ML 250 BlueTEC
4MATIC
Approx. 10.7 US qt
(10.1 l) ML 350 Blue-
TEC 4MATIC
Approx. 12.2 US qt
(11.5 l) AMG vehicles
Approx. 13.1 US qt
(12.4 l) i
Use MB 325.0 or MB 326.0 antifreeze/
corrosion inhibitor. Windshield washer system
Important safety notes G
WARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
! Do not add distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
When handling washer fluid, observe the
important safety notes on service products
(Y page 447). 454
Service products and filling capacitiesTechnical data