Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9807421) - 2017 - CRC - 11/18/15
182 Driving and Operating
Each time the vehicle is started, it
will return to Normal Mode.
Mountain Mode
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 0169 and
Electric Drive Unit 0186.
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 0138.
The engine may run when Mountain
Mode is selected, depending on the
high voltage battery charge, to build
reserve battery charge for uphill
climbs. If Mountain Mode is entered
with a sufficient battery charge
reserve, the battery charge reserve
will appear grayed out and any
battery charge reserve still unused
upon exiting Mountain Mode will
return to normal appearance. 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 to
maintain a smaller battery charge
reserve for normal driving.
Hold Mode
Use Hold Mode on a trip where it is
expected that all of the electric
charge will be depleted. Use Hold
Mode mainly during highway or high
speed driving to maximize both EV
miles and fuel efficiency.
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 183
Hold Mode is only available when
the vehicle is in Electric Mode. This
mode places the remaining battery
charge into a reserve for the driver
to use as desired. Selecting this
mode transitions the vehicle to
Extended Range Mode to maintain
the battery charge reserve.
Upon exiting Hold Mode, the
reserved battery charge becomes
available again and the vehicle
returns to Electric Mode. If the
transition is from Hold Mode directly
to Mountain Mode, the electric
range displayed adjusts for the
Mountain Mode charge reserve.
Hold Mode will not change normal
vehicle acceleration or braking
performance.
Press MODE to select Hold 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.Out of Fuel/Engine
Unavailable
If the vehicle runs out of fuel, or the
engine will not start due to a
malfunction, the vehicle can
continue to be driven in Electric
Mode until the current charge is
depleted. The vehicle will have less
responsive acceleration. DIC
messages indicate reduced
propulsion power, that the engine is
not available, and the need for fuel
or service.
Once the vehicle is refueled, or the
malfunction is corrected, the engine
will start the next time the vehicle is
turned on to perform a self test, and
DIC messages will not be displayed.
Once the engine starts successfully,
normal operation will continue in
either Electric or Extended Range
Mode. The engine may stop running
after the self test is completed,
based on the current mode of
operation. SeeFuel System
Messages 0135 andService
Vehicle Messages 0139.
Maintenance Modes
Engine Maintenance Mode (EMM)
EMM runs the engine to keep it in
good working condition after
approximately six weeks of no or
very limited engine operation. EMM
will force the engine to run, even if
there is a charge to power the
vehicle.
When EMM is needed, the EMM
Request screen appears on the
center stack display at vehicle start.
If Yes is selected, EMM will begin.
The engine will not start until after a
short delay once shifted into
D (Drive). The engine will run for a
set amount of time without turning
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9807421) - 2017 - CRC - 11/18/15
184 Driving and Operating
off. During EMM, a DIC message
displays to show the
EMM percentage complete.
If No is selected, the EMM Request
screen will appear when the vehicle
is next started. The EMM request
can be delayed for up to one day.
If the EMM request was delayed for
one day, EMM will automatically
start the engine at the next vehicle
start. The engine will not start until
after a short delay once shifted into
D (Drive).
An EMM Notification screen will
appear in the center stack display.
If the vehicle is shut off during EMM,
it will restart the next time the
vehicle is driven.
A message displays to indicate that
EMM is active.
If EMM is required and the fuel level
is low, EMM 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. SeePropulsion Power
Messages 0138.
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
center stack 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.
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 185
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 center
stack 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. SeePropulsion Power
Messages 0138. After FMM has
run it is recommended to fill the
fuel tank.
Engine Exhaust
{Warning
Engine exhaust contains carbon
monoxide (CO) which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:
. The engine is running in
Extended Range Mode in
areas with poor ventilation
(parking garages, tunnels,
or deep snow that may
block underbody airflow or
tail pipes).
. The exhaust smells or
sounds strange or different.
. The exhaust system leaks
due to corrosion or damage.
. The vehicle exhaust system
has been modified,
damaged, or improperly
repaired.
(Continued)
Warning (Continued)
.There are holes or openings
in the vehicle body from
damage or aftermarket
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle: . Drive it only with the
windows completely down.
. Have the vehicle repaired
immediately.
Never park with the engine
running in Extended Range Mode
in an enclosed area such as a
garage or a building that has no
fresh air ventilation.
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 187
on the shift lever, then push the shift
lever all the way into P (Park) as
you maintain brake application.
Then press the shift lever button
and move the shift lever into
another gear. SeeShifting out of
Park 0178.
R : Use this gear to back up.
Caution
Shifting to R (Reverse) while the
vehicle is moving forward could
damage the electric drive unit.
The repairs would not be covered
by the vehicle warranty. Shift to
R (Reverse) only after the vehicle
is stopped.
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the electric drive unit, see
If the Vehicle Is Stuck 0171. N :
In this position, the propulsion
system does not provide power to
the wheels. The high voltage battery
is neither charged or discharged
when in N (Neutral) at low vehicle
speeds.
D : This position is for normal
driving. It provides the best fuel
economy. If more power is needed
for passing, press the accelerator
pedal to gain the desired
acceleration
Caution
If the vehicle seems to accelerate
slowly or not respond when you
go faster, and you continue to
drive the vehicle that way, you
could damage the electric drive
unit. Have the vehicle serviced
right away. L :
This position reduces vehicle
speed without using the brakes. Use
L (Low) on very steep hills, in deep
snow, in mud, or in stop-and-go
traffic.
Caution
Spinning the tires or holding the
vehicle in one place on a hill
using only the accelerator pedal
may damage the electric drive
unit. The repair will not be
covered by the vehicle warranty.
If you are stuck, do not spin the
tires. When stopping on a hill, use
the brakes to hold the vehicle in
place.
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9807421) - 2017 - CRC - 11/18/15
230 Driving and Operating
Fuel
GM recommends the use of TOP
TIER Detergent Gasoline to keep
the engine cleaner and reduce
engine deposits. See
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with aposted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:
. For vehicles which are not
FlexFuel, fuel labeled
greater than 15% ethanol by
volume, such as mid-level
ethanol blends (16 –50%
ethanol), E85, or FlexFuel.
. Fuel with any amount of
methanol, methylal, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
. Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(Continued)
Caution (Continued)
(MMT), which can damage
the emissions control
system and spark plugs.
. Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and performance,
and may decrease the life of
the emissions catalyst.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
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Driving and Operating 231
vehicle may not pass a smog-check
test. SeeMalfunction Indicator
Lamp (Check Engine Light) 0109.
If this occurs, return to your
authorized dealer for diagnosis. If it
is determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see “Prohibited
Fuels” inFuel 0230.
Fuel Additives
To keep fuel systems clean, TOP
TIER Detergent Gasoline is
recommended. See Fuel0230.
If TOP TIER Detergent Gasoline is
not available, one bottle of GM Fuel
System Treatment Cleaner added to
the fuel tank at every engine oil
change, can help. GM Fuel System
Treatment Cleaner is the only gasoline additive recommended by
General Motors. It is available at
your dealer.
Filling the Tank
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
. To help avoid injuries to you
and others, read and follow
all the instructions on the
fuel pump island.
. Turn off the engine when
refueling.
. Keep sparks, flames, and
smoking materials away
from fuel.
. Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not re-enter the vehicle
while pumping fuel.
(Continued)
Warning (Continued)
.Keep children away from
the fuel pump and never let
children pump fuel.
. Fuel can spray out if the fuel
cap is opened too quickly.
This spray can happen if the
tank is nearly full, and is
more likely in hot weather.
Open the fuel cap slowly
and wait for any hiss noise
to stop, then unscrew the
cap all the way.
The fuel system on this vehicle
requires a refueling process to
control evaporative emissions. To
refuel the vehicle:
Chevrolet VOLT Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9807421) - 2017 - CRC - 11/18/15
232 Driving and Operating
1. Press the fuel door button onthe driver door for one second.
A WAIT TO REFUEL message
displays on the Driver
Information Center.
2. When the READY TO REFUELmessage displays, the fuel
door on the passenger side will
unlock. To open the fuel door,
push and release the rearward
center edge of the door.
3. Turn the fuel cap counterclockwise to remove.
While refueling, hang the fuel
cap tether from the hook on the
inside of the fuel door.
Complete refueling within
30 minutes of pressing the fuel
door button on the driver door.
If refueling after more than
30 minutes, press the fuel door
button again.
4. After refueling, reinstall the fuel cap by turning it clockwise until
it clicks. Close the fuel door.{Warning
Overfilling the fuel tank by more
than three clicks of a standard fill
nozzle may cause:
. Vehicle performance issues,
including engine stalling and
damage to the fuel system.
. Fuel spills.
. Potential fuel fires.
Be careful not to spill fuel. Wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care 0314.