Mercedes-Benz 2010 M-Class Operator's Manual page 305

Vehicle
Problem
The yellow fuel tank
reserve warning lamp in
the fuel gauge comes
on while driving.
Engine
Problem
! (USA only)
; (Canada only)
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.
! (USA only)
; (Canada only)
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.
Possible causes/consequences and M Solutions
The fuel level has gone below the reserve mark.
X
Refuel at the next gas station.
Possible causes/consequences and M Solutions
There may be a malfunction in
the fuel management system
R
the ignition system
R
the emission control system
R
systems which affect emissions
R
Such malfunctions may result in excessive emissions values and
may switch the engine to limp-home (emergency operation) mode.
X
Have the vehicle checked as soon as possible at an authorized
Mercedes-Benz Center.
i
Some states may by law require you to visit a workshop as
soon as the engine malfunction indicator lamp comes on. Check
local requirements.
A loss of pressure has been detected in the fuel system. The fuel
cap may not be closed properly or the fuel system may be leaky.
X
Check the fuel cap (
X
If it is not closed properly: Close the fuel cap.
X
If it is closed properly: Have the fuel system checked by an
authorized Mercedes-Benz Center.
Diesel engine: Your fuel tank was driven empty.
X
After refueling, start, turn off and restart the engine three or four
times in succession.
The limp-home mode is canceled. You do not need to have your
vehicle checked.
Y page 210).
What to do if ...
Z
303