Mercedes-Benz 2013 CLS Coupe, Owner'S Manual

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Problem Possible causes/consequences and
M
Solutions
?
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 mal-
functioning.
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 traf-
fic conditions, and switch off the engine.
X
Secure the vehicle against rolling away (
Y
page 180).
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 339).
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
under 120 †. The engine may otherwise be damaged.
X
Drive to the nearest qualified specialist workshop.
X
Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic.
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. 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.
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.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (
Y
page 180).
302
Warning and indicator lamps in the instrument cluster
On-board computer and displays