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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
DRIVING AND OPERATING
229
will result in reduced, or no power. An
adequate fuel level must be
maintained in the vehicle to keep it
operational.
Fuel Maintenance Mode (FMM)
FMM tracks average fuel age. Old fuel
can cause engine problems. If low
engine usage causes average fuel age
to exceed approximately one year,
FMM will run the engine to use up
the old fuel. The engine will run until
enough fresh fuel is added to bring
the average fuel age into an
acceptable range. Allowing more old
fuel to be used up by FMM and
adding a larger amount of fresh fuel
will maximize the length of time
before another fuel maintenance
mode is needed. During FMM the
engine may turn on and off.
When FMM is needed, the FMM
Request screen appears on the
infotainment display at vehicle start.
If Yes is selected, FMM will begin. The
engine will not start until after a short
delay once shifted into D (Drive). FMM
will automatically continue at each
vehicle start until fresh fuel is added.
If No is selected, the FMM Request
screen will appear when the vehicle is
next started. The FMM request can be
delayed for only one day.
If the FMM request was delayed for
one day, FMM will start at the next
vehicle start and display the FMM
Notification screen on the
infotainment display. The engine will
not start until after a short delay once
shifted into D (Drive).
If FMM is required and the fuel level
is low, FMM may eventually empty
the fuel tank if fuel is not added. This
will result in reduced, or no power. An
adequate fuel level must be
maintained in the vehicle to keep it
operational. After FMM has run it is
recommended to fill the fuel tank.