Mercedes-Benz S-Class 2011 - Manual (Page 420)

Engine
Problem Possible causes/consequences and M Solutions
;
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
the fuel system
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states/provinces, you are required by law to visit a
qualified specialist workshop as soon as the Check Engine
warning lamp lights up. If necessary, check whether this is the
case in the state/province you are in.
The yellow reserve fuel
warning lamp flashes
while the engine is
running. 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
workshop.
The yellow reserve fuel
warning lamp lights up
while the engine is
running. The amount of fuel in the tank has dropped into the reserve range.
X Refuel at the nearest gas station.
418
Warning and indicator lamps in the instrument cluster
On-board computer and displays