Mercedes-Benz CLS Operator's Manual page 252

Warning and indicator lamps in the instrument cluster
250
Problem
?
The red coolant
warning lamp comes on
while the engine is
running.
?
The red coolant
warning lamp comes on
while the engine is
running. A warning tone
also sounds.
Possible causes/consequences and M Solutions
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
Allow the engine and coolant to cool.
X
Check the coolant level and add coolant (
the warning notes.
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 under 248 ‡ (120 †), drive to the next
qualified specialist workshop.
X
Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.
The coolant temperature has exceeded 248 ‡ (120 †). The
airflow to the engine radiator may be blocked or the coolant level
may be too low.
The engine is not being cooled sufficiently and may be damaged.
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
Allow the engine and coolant to cool.
X
Check the coolant level and add coolant (
the warning notes.
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 under 248 ‡ (120 †), drive to the next
qualified specialist workshop.
X
Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.
I n f o r ma t i o n P r o v i d e d b y :
Y page 282). Observe
Y page 282). Observe