2012 MERCEDES-BENZ E-Class SEDAN coolant level

ProblemPossible 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.XObserve the additional display messages in the multifunction
display.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add coolant (Y page 311). Observe
the warning notes.XIf you need to add coolant more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.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-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.
The engine is not being cooled sufficiently and may be damaged.XObserve the additional display messages in the multifunction
display.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add coolant (Y page 311). Observe
the warning notes.XIf you need to add coolant more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.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-and-go traffic.Warning and indicator lamps in the instrument cluster269On-board computer and displaysZ

Further information on engine oil
( Y page 387).
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 145) in the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 145).XCheck the coolant temperature display in
the instrument cluster.
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) above marker bar = in the filler
neck when warm, there is enough coolant
in coolant expansion tank ;.XIf necessary, add coolant that 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 389).
Windshield washer system and
headlamp cleaning system
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
i Vehicle components and their service
products must match. You should,
therefore, only use products that have been
tested and approved by Mercedes-Benz.
Information on tested and approved
products can be obtained at any authorized
Mercedes-Benz Center or on the Internet at
http://www.mbusa.com (USA only).
Engine compartment311Maintenance and careZ

fluids can be obtained from any authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
Coolant
Important safety notes
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
The engine cooling system is filled at the
factory with coolant that contains an
antifreeze/corrosion inhibitor that ensures
protection down to approximately -35 ‡
(-37 †).
! Only add coolant that has been premixed
with the desired antifreeze protection.
Otherwise, the engine could be damaged.
Further information on coolants and on
filling can be found in the Mercedes-Benz
Specifications for Service Products, MB
Approval 310.1, e.g. on the Internet at
http://bevo.mercedes-benz.com . You can
also consult an authorized Mercedes-Benz
Center.
! 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.
If the coolant has antifreeze protection down
to -35 ‡ (-37 †), the boiling point of the
coolant under operating conditions is
approximately 266 ‡ (130 †).
Your vehicle has a range of aluminum
components. Aluminum components in the
engine make it necessary to use antifreeze/
corrosion inhibitor coolant that has been
specifically formulated to protect the
aluminum parts. Using other antifreeze/
corrosion inhibitors without these
characteristics affects the service life.
The coolant must be used throughout the year
in order to maintain the necessary corrosion
protection and to 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 engine cooling system
design. The renewal interval in the Service
Booklet is only valid if the coolant is renewed
or filled up with Mercedes-Benz approved
products. Therefore, only use MB 325.0 or
326.0 anticorrosion/antifreeze or another
Mercedes-Benz approved product of the
same specification.
Information on other products with the same
specifications that are approved by
Mercedes-Benz can be obtained at an
authorized Mercedes-Benz Center or on the
Internet at http://bevo.mercedes-benz.com.
The coolant is checked at every maintenance
interval at an authorized Mercedes-Benz
Center.
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 to
-49 ‡ [-45 † ]); otherwise, heat will not
dissipate as effectively.
If the coolant level is too low, MB 325.0 or
326.0 anticorrosion/antifreeze should be
added. Have the engine cooling system
checked for possible leaks.
Windshield/headlamp cleaning
system
GWARNING
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
Service products and capacities389Technical dataZ