2015 MERCEDES-BENZ S-Class COUPE check engine

Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 00AC
0051
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 166).
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 322).
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 257 ‡
(125 †). 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. 00AC
0051
The red coolant warning lamp comes on while the engine is running. A
warning tone also sounds.
The coolant temperature has exceeded 255 ‡ (124 †). 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 166).288
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 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 322).
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 At coolant temperatures below 257 ‡(125 †), you can continue driving 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. Driving systems
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00BA
0051
The red distance warning lamp lights up while the vehicle is in motion. A
warning tone also sounds.
You are approaching a vehicle 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 73).
For further information about the distance warning function of COLLISION
PREVENTION ASSIST PLUS, see (Y page 69). Warning and indicator lamps in the instrument cluster
289On-board computer and displays Z

Vehicle
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00CC
0051
The red power steering warning lamp is lit while the engine is running.
The power steering is malfunctioning.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident. X Check whether you are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified specialist
workshop.
X If you are unable to steer safely: do not drive on. Contact the nearest
qualified specialist workshop. Warning and indicator lamps in the instrument cluster
291On-board computer and displays Z

!
Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield
wipers or the hood. X
Make sure that the windshield wipers are
turned off.
X Pull release lever 0043on the hood.
The hood is released. X
Reach into the gap, pull hood catch han-
dle 0044up and lift the hood.
Once you have lifted the hood about
15 inches (40 cm), it is automatically
opened the rest of the way and held open
by the gas-filled struts.
Closing the hood X
Lower the hood and let it fall from a height
of approximately 8 in (20 cm).
X Check that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per 600 miles (1,000 km). The oil consumption
may be higher than this when the vehicle is
new or if you frequently drive at high engine
speeds.
Depending on the engine, the oil dipstick may be in a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly, wait about 30 minutes
before carrying out the measurement.
Checking the oil level using the oil dip-
stick (except S 65 AMG) 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. Engine compartment
319Maintenance and care Z

Checking the oil level using the on-board computer (S 65 AMG)
X
Make sure that the SmartKey is in position 2in the ignition lock.
X Use 00E2 on the steering wheel to call up the list of menus.
X Press the 0064or0063 button on the steering wheel to select the Service
Servicemenu.
X Confirm by pressing 0076on the steering wheel.
X Use 0064 or0063 to select the Engine Oil Level
Engine Oil Level submenu.
X Press 0076to confirm the selection.
The Measuring
Measuring engine
engineoil
oillevel
level accurate
accurate only
onlywhen
whenvehicle
vehicle is
islevel
level message
appears in the multifunction display.
The measurement takes a few seconds. You will see one of the following messages in the
multifunction display: Display messages
Possible causes/consequences and
0050
0050Solutions Engine
Engine
Oil
OilLevel
Level OK
OK The oil level is correct.
Check Engine Oil
Check Engine Oil
Level Level
(Add
(Add1
1Liter)
Liter) The oil level is too low.
X Top up 1.1 US qt (1.0 liter) of engine oil. Reduce Engine Oil
Reduce Engine Oil
Level Level The engine oil level is too high.
X Have excess engine oil siphoned off. For Engine Oil
For Engine Oil
Level Ignition Level Ignition
Must Be On Must Be On The ignition is switched off.
X Turn the SmartKey to position 2in the ignition lock. Need More Time to
Need More Time to
Check Engine Oil Check Engine Oil
Level Level The required waiting period was not observed.
X If the engine is at normal operating temperature: repeat the
measurement after about five minutes.
If the engine is not at normal operating temperature, e.g. if the
engine was only started briefly: repeat the measurement after
approximately 30 minutes. Engine Oil Level Engine Oil Level
Not Measurable Not Measurable
with with
Engine
Engine Running
Running The engine is running; oil level measurement is not possible.
X Switch off the engine.
X If the engine is at normal operating temperature: wait about five
minutes before carrying out the measurement.
If the engine is not at normal operating temperature, e.g. if theengine was only started briefly: wait approximately 30 minutes before carrying out the measurement. Adding engine oil
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. Engine compartment
321Maintenance and care
Z

Where possible, let the engine cool down and
touch only the components described 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 is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine. H
Environmental 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 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
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
X Turn cap 0043counter-clockwise and remove
it.
X Add engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, add 1.1 US qt (1.0 l)of
engine oil.
X Replace cap 0043on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.
X Check the oil level again with the oil dip-
stick (Y page 319).
Further information on engine oil
(Y page 393). Additional service products
Checking coolant level 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
The engine cooling system is pressurized, par- ticularly when the engine is warm. When 322
Engine compartmentMaintenance and care

opening the cap, you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape. X
Park the vehicle on a level surface.
Only check the coolant level when the vehi- cle is on a level surface and the engine has
cooled down.
X Turn the SmartKey to position 2in the igni-
tion lock (Y page 147).
or
X Press Start/Stop button twice
(Y page 147).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position
0(Y page 147) in the ignition lock.
or
X Remove Start/Stop button from ignition
lock (Y page 147).
X Slowly turn cap 0043half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap 0043further counter-clockwise and
remove it.
If the coolant is at the level of marker bar 0087
in the filler neck when cold, there is enough coolant in coolant expansion tank 0044.If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar 0087in the filler
neck when warm, there is enough coolant
in expansion tank 0044.
X If necessary, add coolant that has been tes-
ted and approved by Mercedes-Benz.
X Replace cap 0043and turn it clockwise as far
as it will go.
For further information on coolant, see
(Y page 395).
Adding washer fluid to the windshield
washer system 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
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. X
To open: pull cap0043upwards by the tab.
X Place cap 0043on the edge of the filler neck
and engage in place. Engine compartment
323Maintenance and care Z

the ASSYST PLUS service interval display
after the service work has been carried out.
You can also obtain further information on
maintenance work, for example.
Special service requirements The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions
or increased load on the vehicle, mainte-
nance work must be carried out more fre-
quently, for example:
R regular city driving with frequent intermedi-
ate stops
R if the vehicle is primarily used to travel
short distances
R use in mountainous terrain or on poor road
surfaces
R if the engine is often left idling for long peri-
ods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist work- shop, e.g. an authorized Mercedes-Benz Cen-ter.
Driving abroad An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any author-
ized Mercedes-Benz Center. Care
General notes
H
Environmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible man-
ner. !
For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
! Do not park the vehicle for an extended
period straight after cleaning it, particularly after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
brake pads/linings. For this reason, you
should drive for a few minutes after clean-
ing. Braking heats the brake discs and the
brake pads/linings, thus drying them. The
vehicle can then be parked.
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents rec-
ommended and approved by Mercedes-Benz. Washing the vehicle and cleaning the
paintwork
Automatic car wash G
WARNING
Braking efficiency is reduced after washing
the vehicle. There is a risk of an accident.
After the vehicle has been washed, brake
carefully while paying attention to the traffic
conditions until full braking power is restored. Care
325Maintenance and care Z