Mercedes-Benz M-Class Owner's Manual page 294

Warning and indicator lamps in the instrument cluster
Problem
8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
?
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.
Possible causes/consequences and M Solutions
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
Refuel at the nearest filling station.
X
The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
Stop the vehicle immediately, paying attention to road and traf-
X
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
Apply the electric parking brake.
X
Consult a qualified specialist workshop.
X
291
Z