2015 MERCEDES-BENZ SLK-Class coolant temperature

Display messages
Possible causes/consequences and
0050
0050Solutions 00AC
Coolant Too Hot Coolant Too Hot
Stop Vehicle Turn Stop Vehicle Turn
Engine Off Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
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 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 161).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
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 display message goes out
and the coolant temperature is below 248 ‡ (120 †). Other-
wise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). 003D
See See
Operator's
Operator's Man‐
Man‐
ual
ual The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
! Do not continue driving. The engine could otherwise overheat.
X Secure the vehicle against rolling away (Y page 161).
X Consult a qualified specialist workshop. Display
messages
229On-board computer and displays Z

Engine
Problem
Possible causes/consequences and
0050
0050Solutions 00B9
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, 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
in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified special-
ist workshop as soon as the yellow Check Engine warning lamp
lights up. This depends on the locally applicable legal require-
ments. If in doubt, check whether such legal regulations apply in the state in which you are currently driving. 00B6
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. 00B6
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the
00B9
Check Engine warning
lamp may light up. The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist work-
shop. 00AC
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the start of the scale. The temperature sensor for the coolant temperature gauge is
defective.
The coolant temperature is no longer being monitored. There is a risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.
X Secure the vehicle against rolling away (Y page 161).
X Consult a qualified specialist workshop. Warning and indicator lamps
251On-board computer and displays Z

Problem
Possible causes/consequences and
0050
0050Solutions 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
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 malfunc-
tioning.
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 161).
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 281).
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 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 moun-
tainous terrain, and stop-and-go traffic. 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds. The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow 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 161).252
Warning and indicator lampsOn-board computer and displays

Problem
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 281).
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 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. Driving systems
Problem
Possible causes/consequences and
0050 0050Solutions 00BA
The red distance warn-
ing 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 DISTRONIC PLUS (Y page 171).
Further information on PRE‑ SAFE®
Brake (Y page 67). Warning and indicator lamps
253On-board computer and displays Z

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 279).
Further information on engine oil
(Y page 349). Checking and adding other 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
opening the cap, you could be scalded by hotcoolant 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. Example 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 139).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 140).
X Check the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position
0(Y page 139) in the ignition lock.
X Slowly turn cap 0044half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap 0044further 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 0043.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar 0087in the fuel
filler neck when warm, there is enough
coolant in expansion tank 0043.
X If necessary, add coolant that has been tes-
ted and approved by Mercedes-Benz.
X Replace cap 0044and turn it clockwise as far
as it will go.
For further information on coolant, see
(Y page 351).
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. Engine compartment
281Maintenance and care Z

Coolant
Important safety notes G
WARNING
If antifreeze comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. 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 BeVo 310.1, e.g.
on the Internet at
http://bevo.mercedes-benz.co m.Or con-
tact 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.
Comply with the important safety precautions for service products when handling coolant
(Y page 347).
The coolant is a mixture of water and anti-
freeze/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 cool- ant during operation is approximately 266 ‡
(130 †).
The antifreeze/corrosion inhibitor concentra- tion 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
do wn 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 accord-
ance with MB Specifications for Service Prod-
ucts 310.1.
i When the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures
adequate antifreeze and corrosion protec-
tion.
i The coolant is checked with every main-
tenance interval at a qualified specialist
workshop.
Filling capacities Missing values were not available at time of
going to print.
Model Capacity
SLK 250
Approx. 10.1 US qt
(9.6l) SLK 350
Approx. 11.0 US qt
(10.4l) SLK 55 AMG
i
Use MB 325.0 or MB 326.0 approved
antifreeze/corrosion inhibitor. Service products and filling capacities
351Technical data Z