2014 MERCEDES-BENZ E-SEDAN engine overheat

Problem Possible causes/consequences and
M
MSolutions ?
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 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 339).
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.
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 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).294
Indicator and warning lamps in the instrument clusterOn-board computer and displays
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment 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
specialist workshops: (Y page 26).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
overheated 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 keep clothing away from moving parts G
WARNING
The ignition system and the fuel injection
system 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
system or fuel injection system when the
ignition is switched on. G
WARNING
Hybrid vehicles: be sure to read the "HYBRID"
supplement. Otherwise, you could fail to
recognize dangers.
Opening the hood G
WARNING
Certain components in the engine
compartment, 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. 336
Engine compartmentMaintenance and care
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Information on refueling (Y
page 176).
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
recommended by Mercedes-Benz. Comply
with the instructions for use on the product
label. More information about
recommended additives can be obtained
from any authorized Mercedes-Benz
Center.
Mercedes-Benz recommends that you use
fuel brands that have the additives.
The quality of the fuel available in some
countries may not be sufficient. Residue
could build up as a result. In such cases, and
in consultation with an authorized Mercedes-
Benz Center, the gasoline may be mixed with
the cleaning additive recommended by
Mercedes-Benz (part no. A000989254512).
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.
! Only use commercially available vehicular
ULTRA-LOW SULFUR DIESEL FUEL (ULSD,
15 ppm maximum sulfur content) that
meets the ASTM D975 standard. If you do
not refuel with ULSD, you may damage the
BlueTEC exhaust gas aftertreatment
system of the vehicle. !
Do not use gasoline to refuel vehicles with
a diesel engine. Do not mix diesel fuel with
gasoline, kerosene or paraffin. This may
otherwise result in damage to the fuel
system and engine.
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
assistance.
i For further information, consult a
qualified specialist workshop or on the
Internet at http://www.mbusa.com (USA
only).
Information on refueling (Y page 176).
Low outside temperatures
i Diesel fuel with improved cold flow
properties is available during the winter
months. Further information about fuel
properties can be obtained from oil
companies, e.g. at gas stations.
Flexible Fuel vehicles Important safety notes
G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children. 420
Service products and filling capacitiesTechnical data
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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 an engine oil with an SAE classification
(viscosity) suitable for the prevailing outside
temperatures. The table shows you which
SAE classifications are to be used. The low-
temperature characteristics of engine oils
can deteriorate significantly, e.g. as a result
of aging, soot and fuel deposits. It is therefore
strongly recommended that you carry out
regular oil changes using an approved engine
oil with the appropriate SAE classification. Brake fluid
G
WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. 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. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
Comply with the important safety notes for
service products when handling brake fluid
(Y page 418).
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 regularly replaced at
a qualified specialist workshop and the
replacement confirmed in the Maintenance
Booklet. 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.
i Have the coolant regularly replaced at a
qualified specialist workshop and the
replacement confirmed in the Maintenance
Booklet. Service products and filling capacities
423Technical data Z
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