Warning/
indicator
lamp
N
N
Signal type
Possible causes/consequences and
M
M
Solutions
?
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 display messages.
X
Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X
Secure the vehicle to prevent it from rolling away (
Y
page 133).
X
Exit 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 245).
X
If you have to add coolant more frequently, have the engine cooling system
checked.
X
Make sure that the air supply to the radiator is not obstructed, by frozen slush
for example.
X
Check the coolant temperature:
R
using the display in the on-board computer on vehicles without steering wheel
buttons (
Y
page 173)
R
using the analog display in the instrument cluster on vehicles with steering
wheel buttons (
Y
page 38)
X
Do not start the engine again until the coolant temperature is below the maxi-
mum value specified below. The engine could otherwise be damaged.
X
Drive to the nearest qualified specialist workshop.
Avoid heavy loads on the engine, e.g. driving in mountainous terrain, and stop-
and-go traffic.
Under normal operating conditions and with the specified coolant level, the cool-
ant temperature gage may rise to 248 ‡ (120 †).
?
N
The red coolant warning lamp comes on while the engine is running. An addi-
tional warning tone sounds.
The coolant temperature has exceeded the maximum value specified below. 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 adequately and could become damaged.
Never drive with an overheated engine. Otherwise, fluids which may have leaked
into the engine compartment could catch fire.
In addition, steam from an overheated engine can cause serious burns, which can
occur just by opening the hood.
There is a risk of injury.
X
Observe the display messages.
X
Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X
Secure the vehicle to prevent it from rolling away (
Y
page 133).
Indicator and warning lamps in the instrument cluster
225
On-bo
ard
co
mput
er
and
displays
Z
