Chevrolet Volt 2016 Owner's Manual page 180

During some conditions, certain
drive modes may be unavailable.
The unavailable mode is grayed out
in the DIC menu and cannot be
selected.
If in Sport, Mountain, or Hold Mode,
the mode may become unavailable
and the vehicle will return to Normal
Mode. The indicator light goes off
and a DIC message displays. See
Propulsion Power Messages 0 136.
The vehicle will stay in Normal
Mode at the next restart.
Sport Mode
Sport Mode provides more
responsive acceleration than
Normal Mode, but can reduce
efficiency. Use Normal Mode
whenever possible.
Press MODE to select Sport Mode.
Press MODE again to return to
Normal Mode and it becomes active
after three seconds.
Each time the vehicle is started, it
will return to Normal Mode.
Mountain Mode
Driving and Operating
Mountain Mode should be selected
at the beginning of a trip before
climbing steep, uphill grades and
when expecting to drive in very hilly
or mountainous terrain. This mode
maintains a reserve electrical
charge of the high voltage battery to
provide better grade climbing
performance. While driving in
Mountain Mode, the vehicle will
have less responsive acceleration.
Mountain Mode will not change
normal vehicle braking performance
for steep downhill grades. See Hill
and Mountain Roads 0 167 and
Electric Drive Unit 0 184.
Press MODE to select Mountain
Mode. If steep hill driving is
expected, it is recommended to
select Mountain Mode at least
20 minutes before driving on steep
grades. This will allow the vehicle
time to build a sufficient battery
charge reserve.
If Mountain Mode is not selected for
these conditions, propulsion power
may be reduced and the engine
speed may increase. See
Propulsion Power Messages 0 136.
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