coolant temperature MERCEDES-BENZ S-CLASS SEDAN 2012 User Guide

GWARNING
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam from an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
! If the coolant temperature is over 248 ‡ (120 †), do not continue driving. The engine will
otherwise be damaged.
Display messagesPossible causes/consequences and M Solutions?The engine fan is defective.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 battery is not being charged.
Possible causes are:
R a defective 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 not damaged:
XVisit a qualified specialist workshop.Display messages407On-board computer and displaysZ

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 Please read the information on qualified
specialist workshops ( Y page 31).
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
Hybrid vehicles: be sure to read the "HYBRID"
supplement. Otherwise, you could fail to
recognize dangers.
GWARNING
Do not open the hood when the engine is
overheated. You could be seriously injured.
Observe the coolant temperature gauge 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 avoid 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 30seconds or may even restart
after the engine has been switched off. For
this reason, you must not reach into the fan
rotation area.
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.
458Engine compartmentMaintenance and care

HEnvironmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful
to the environment.
! Only use engine oils and oil filters that
have been approved for vehicles with a
service system. You can obtain a list of the
engine oils and oil filters tested and
approved in accordance with the
Mercedes-Benz Specifications for Service
Products at any Mercedes-Benz Service
center.
Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters that have
not been specifically approved for the
service system
R replacing engine oil and oil filters after
the interval for replacement specified by
the service system has been exceeded
R using engine oil additives.
! Do not add too much oil. adding too much
engine oil can result in damage to the
engine or to the catalytic converter. Have
excess engine oil siphoned off.
Example: engine oil cap
XTurn cap : counterclockwise and remove
it.XAdd engine oil.
Vehicles with oil level measurement
function in the on-board computer: observe
the information in the on-board computer
when doing so. Vehicles with oil dipstick: if
the oil level is at or below the MIN mark onthe oil dipstick, add 0.55 to 1.1 US qt (0.5
to 1.0 l) engine oil.XReplace cap : on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.XCheck the oil level again with the oil
dipstick ( Y page 460) or the on-board
computer ( Y page 460).
Further information on engine oil
( Y page 528).
Checking and adding other service
products
Checking the coolant level
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.
Engine compartment463Maintenance and careZ

XPark 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.XTurn the SmartKey to position 2 in the
ignition lock ( Y page 307).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 307).XCheck the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).XTurn the SmartKey to position
0 (Y page 307) in the ignition lock.XSlowly turn cap : half a turn
counterclockwise to allow excess pressure
to escape.XTurn cap : further counterclockwise 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 level 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 530).
Adding washer fluid to the windshield
washer system/headlamp cleaning
systemGWARNING
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.
Example: washer fluid reservoir
Depending on the engine, the washer fluid
reservoir may be installed in different
locations.
XTo open: pull cap : upwards by the tab.XAdd the premixed washer fluid.XTo close: press cap : onto the filler neck
until it engages.
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
Further information on windshield washer
fluid/antifreeze ( Y page 531).
Brake fluid level
! If the brake fluid level in the brake fluid
reservoir has fallen to the MIN mark or
below, check the brake system
immediately for leaks. Also check the
thickness of the brake linings. Visit a
qualified specialist workshop immediately.
Do not add brake fluid. This does not
correct the malfunction.
464Engine compartmentMaintenance and care

intervals can be found in the Maintenance
Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake fluid
can be obtained at any qualified specialist
workshop or on the Internet at
http://bevo.mercedes-benz.com.
Coolant
Important safety notes
GWARNING
Antifreeze is highly flammable. Fire, naked
flames and smoking are prohibited when
handling antifreeze.
If antifreeze comes into contact with hot
engine parts, it may ignite and you could burn
yourself. Do not spill any antifreeze on hot
engine parts.
! 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.
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 under operating conditions 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.
CapacityModelCapacityS 550 35
S 550 4MATIC 35Approximately
14.5 US qt (13.7 l)S 600Approximately
15.3 US qt (14.5 l)S 63 AMGApproximately
12.2 US qt (11.5 l)S 65 AMGApproximately
14.7 US qt (13.9 l)S 350 BlueTEC
4MATICApproximately
12.0 US qt (11.4 l)35 BlueEFFICIENCY530Service products and filling capacitiesTechnical data