Mercedes-Benz S-Class 2014 Owners Manual - Manual (Page 310)

Engine
Warning/
indicator
lamp
N N Signal type
Possible causes/consequences and M
M Solutions
; N 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 (for vehicles with gasoline engines)
R in the fuel system
The emission limit values may be exceeded and the engine may be in
emergency mode.
X Have the vehicle checked as soon as possible at a qualified specialist
workshop.
i In some states, you must immediately visit a qualified specialist workshop
as soon as the yellow Check Engine warning lamp lights up. This is due to
the legal requirements in effect in these states. If in doubt, check whether
such legal regulations apply in the state in which you are currently driving.
8 N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station.
8 N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ; Check Engine warning lamp may light up.
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.
308
Warning and indicator lamps in the instrument cluster
On-
boar
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comp
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and
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