2015 MERCEDES-BENZ S-CLASS COUPE engine coolant

Display messages
Possible causes/consequences and
M
MSolutions ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious
burns, which can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 125 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, consult a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant level, the coolant temperature may rise to 124 †. #
See Owner's Manual See Owner's Manual The battery is not being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).
X Consult a qualified specialist workshop. 284
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions #
Stop vehicle See Stop vehicle See
Owner's Manual Owner's Manual The battery is no longer being charged and the battery charge level
is too low.
A warning tone also sounds.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).
X Observe the instructions in the #See Owner's Manual
See Owner's Manual
display message.
X Consult a qualified specialist workshop. #
Start engine See Start engine See
Owner's Manual Owner's Manual The engine is off and the battery charge level is too low.
X Switch off electrical consumers that you do not need, such as
the rear window heating and interior lighting.
X Leave the engine running for a few minutes, or drive for a longer
distance.
The battery charges. 4
Check eng. oil Check eng. oil
lev. when next lev. when next
refuelling refuelling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
! Avoid long journeys when there is too little coolant in the cool-
ing system. Otherwise the engine will be damaged.
X Check the oil level when next refuelling, at the latest
(Y page 340).
X If necessary, top up the engine oil (Y page 342).
X Have the engine checked at a qualified specialist workshop if the
engine oil needs topping up more often than usual.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.co m. Display
messages
285On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions 4
Add Add
1
1litre
litre engine
engine
oil
oil when
when next
next refu‐
refu‐
elling
elling Mercedes-AMG vehicles:
The engine oil level has dropped to the minimum level.
! Avoid long journeys when there is too little coolant in the cool-
ing system. Otherwise the engine will be damaged.
X Check the oil level when next refuelling, at the latest
(Y page 340).
X If necessary, top up the engine oil (Y page 342).
X Have the engine checked at a qualified specialist workshop if the
engine oil needs topping up more often than usual.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.co m.4
Engine oil level Engine oil level
Stop vehicle Stop vehicle
Switch engine off Switch engine off Mercedes-AMG vehicles:
The engine oil level is too low. There is a risk of engine damage.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).
X Check the engine oil level (Y page 340).
X If necessary, top up the engine oil (Y page 342).8
Reserve fuel level Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level
drops into the reserve range.
X Refuel at the nearest filling station. C C There is very little fuel in the fuel tank.
The auxiliary heating cannot be operated.
X Refuel at the nearest filling station without fail. 286
Display messagesOn-board computer and displays

Engine
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ;
N
The yellow engine diagnostics warning lamp lights up while the engine is
running.
There may be a fault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified specialist work-
shop. 8
N
The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level drops into the reserve range.
X Refuel at the nearest filling station. ?
N
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the bar display.
The temperature sensor for the coolant temperature gauge is faulty.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine. Do not continue driving under any circum- stances.
X Safeguard the vehicle against rolling away (Y page 181).
X Consult a qualified specialist workshop. 310
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ?
N
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 Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).
X Leave the vehicle and keep a safe distance from the vehicle until the engine
has cooled down.
X Check the coolant level and top up the coolant, observing the warning notes
(Y page 342).
X If you have to top up the coolant frequently, have the engine cooling system
checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by
frozen slush.
X Do not start the engine again until the coolant temperature is below 125 †.
The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g. driving in
mountainous terrain and stop-start traffic. ?
N
The red coolant warning lamp comes on while the engine is running. A
warning tone also sounds.
The coolant temperature has exceeded 124 †. The airflow to the engine radi- ator may be blocked or the coolant level may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine is overhea-
ted can cause some fluids which may have leaked into the engine compart-
ment to catch fire.
In addition, steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 181).Warning and indicator lamps in the instrument cluster
311On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions X
Leave the vehicle and keep a safe distance from the vehicle until the engine
has cooled down.
X Check the coolant level and top up the coolant, observing the warning notes
(Y page 342).
X If you have to top up the coolant frequently, have the engine cooling system
checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by
frozen slush.
X At coolant temperatures below 125 †, drive to the nearest qualified spe-
cialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Driving systems
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ·
N
The red distance warning lamp lights up while the vehicle is in motion.
The distance to the vehicle in front is too small for the speed selected.
X Increase the distance. ·
N
The red distance warning lamp lights up while the vehicle is in motion. A
warning tone also sounds.
You are approaching a vehicle, a pedestrian or a stationary obstacle in your
line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to brake or take
evasive action.
Further information on PRE ‑SAFE®
Brake (Y page 77).
For further information on the distance warning function of COLLISION PRE-
VENTION ASSIST PLUS, see (Y page 73).312
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Adding engine oil
G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil does not spill out
over the filler neck. Allow the engine to cool
down and thoroughly clean the components
that have come into contact with engine oil
before you start the engine. H
Environmental note
When topping up the 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 ser-
vice 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
Centre.
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 changing the engine oil and oil filter after
missing the change interval required by
the service system
R using engine oil additives
! Do not add too much oil. Topping up with
too much engine oil can result in damage to the engine or to the catalytic converter.
Have excess engine oil siphoned off.
Example
X Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, top up with 1.0 litre of
engine oil.
X Replace cap :on the filler neck and
tighten clockwise.
Make sure that the cap locks securely into place.
X Check the oil level again with the oil dip-
stick (Y page 340).
For further information on engine oil, see
(Y page 407). Other service products
Checking the coolant level G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
The engine cooling system is under pressure, particularly if the engine is warm. You could 342
Engine compartmentMaintenance and care

be scalded by hot coolant spraying out when
opening the cap. There is a danger of injury.
Allow the engine to cool before opening the
cap. Wear gloves and protective eyewear
when opening. Slowly turn the cap half a turn to allow pressure to escape. X
Park the vehicle on a level surface.
Only check the coolant level if the vehicle is on a level surface and the engine has
cooled down.
X Turn the key to position 2in the ignition
lock (Y page 161).
or
X Press the Start/Stop button twice
(Y page 161).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
70 †.
X Turn the key to position 0in the ignition
lock (Y page 161).
or
X Remove the Start/Stop button from the
ignition lock (Y page 161).
X Slowly turn cap :half a turn anti-clock-
wise and allow excess pressure to escape.
X Turn cap :further anti-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 level is approximately 1.5 cm above marker bar =in the filler neck when warm, there is enough coolant in coolant
expansion tank
;.
X If necessary, top up with coolant that has
been tested and approved by Mercedes-
Benz.
X Replace cap :and turn it clockwise as far
as it will go.
For further information on coolant, see
(Y page 409).
Topping up the windscreen washer sys-
tem G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure the windscreen washer concen-
trate does not come into contact with the filler neck. X
To open: pull cap:upwards by the tab.
X Place cap :on the edge of the filler neck
and engage in place. Engine compartment
343Maintenance and care Z