Page 265 of 454

Black plate (27,1)Chevrolet Volt Owner Manual - 2012
Driving and Operating 9-27
The engine may run when Mountain
Mode is selected, depending on
high voltage battery charge, to build
reserve battery charge for uphill
climbs. If Mountain Mode is entered
with a sufficient battery charge
reserve, the estimated electric range
will adjust accordingly and any
battery charge reserve still unused
upon exiting Mountain Mode will be
added back to the electric range
display.
Press the Drive Mode button again
to return to Normal Mode and it
becomes active after three seconds.
The Mountain light comes on when
Mountain Mode is selected. See
Mountain Mode Light on page 5‑24.
Each time the vehicle is started, it
will return to Normal Mode to
maintain a smaller battery charge
reserve for normal driving.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. 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 will stop running
after the self test is completed, and
based on the current mode of
operation. See
Fuel System
Messages on page 5‑50 and
Service Vehicle Messages on
page 5‑54.
Page 266 of 454

Black plate (28,1)Chevrolet Volt Owner Manual - 2012
9-28 Driving and Operating
Maintenance Modes
Engine Maintenance Mode (EMM)
Engine Maintenance Mode (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 run for a set amount
of time without turning 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 only one day.
If the EMM request was delayed for
one day, EMM will automatically
start the engine at the next vehicle
start. An EMM Notification screen
will appear in the center stack
display.If the vehicle shuts 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 on page 5‑52.
Page 267 of 454

Black plate (29,1)Chevrolet Volt Owner Manual - 2012
Driving and Operating 9-29
Fuel Maintenance Mode (FMM)
Fuel Maintenance Mode (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.
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 center
stack display.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. See
Propulsion Power
Messages on page 5‑52.
Page 268 of 454

Black plate (30,1)Chevrolet Volt Owner Manual - 2012
9-30 Driving and Operating
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.
Running the Vehicle
While Parked
It is better not to park with the
propulsion system on. But if you
ever have to, here are some things
to know.
{WARNING
Leaving the engine running in
Extended Range Mode in an
enclosed area with poor
ventilation is dangerous. Engine
exhaust may enter the vehicle.
Engine exhaust contains carbon
monoxide (CO) which cannot be
seen or smelled. It can cause
unconsciousness and even death.
Never run the engine in an
enclosed area that has no fresh
air ventilation. For more
information, see Engine Exhaust
on page 9‑30.
Page 269 of 454

Black plate (31,1)Chevrolet Volt Owner Manual - 2012
Driving and Operating 9-31
{WARNING
It can be dangerous to get out of
the vehicle if the electric drive unit
shift lever is not fully in P (Park)
with the parking brake firmly set.
The vehicle can roll. Do not leave
the vehicle with the propulsion
system on unless you have to.
If you have left the propulsion
system on, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
level ground, always set the
parking brake and move the shift
lever to P (Park).
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park on page 9‑22.
Electric Drive Unit
The vehicle uses an electric drive
unit. The shift lever is on the
console between the seats.
P (Park): This position locks the
front wheels. It is the best position
to use when starting the propulsion
system because the vehicle cannot
move easily.
{WARNING
It is dangerous to get out of the
vehicle if the shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the
propulsion system is running
unless you have to. If you have
left the propulsion system
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
fairly level ground, always set the
parking brake and move the shift
lever to P (Park). See Shifting Into
Park on page 9‑22.
Make sure the shift lever is fully in
P (Park) before starting the
propulsion system. The vehicle has
an electric drive unit shift lock
control system. The regular brake
must be fully applied first and then
the shift lever button pressed before
Page 270 of 454

Black plate (32,1)Chevrolet Volt Owner Manual - 2012
9-32 Driving and Operating
shifting from P (Park) when the
vehicle is in ON/RUN. If you cannot
shift out of P (Park), ease pressure
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 on page 9‑23.
R (Reverse): Use this gear to
back up.
Notice: 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 on page 9‑12. N (Neutral):
In this position, the
propulsion system does not connect
with the wheels.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If more power is
needed for passing, and the
vehicle is:
.Going less than 56 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 56 km/h (35 mph) or
more, push the accelerator all
the way down.
Notice: 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 (Low):
This position reduces
vehicle speed without using the
brakes. You can use L (Low) on
hills. It can help control vehicle
speed going down steep mountain
roads along with using the brakes
off and on. You can use L (Low) on
very steep hills, in deep snow,
or in mud.
Notice: 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.
Page 271 of 454

Black plate (33,1)Chevrolet Volt Owner Manual - 2012
Driving and Operating 9-33
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When propulsion is active and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑23. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Page 272 of 454

Black plate (34,1)Chevrolet Volt Owner Manual - 2012
9-34 Driving and Operating
Electric Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The
Yswitch is on
the center stack. The EPB can
always be activated, even if the
vehicle is off. To prevent draining
the 12‐volt battery, avoid repeated
cycles of the EPB system when the
vehicle is off. In case of insufficient electrical
power, the EPB cannot be applied
or released.
Before leaving the vehicle, check
the Electric Parking Brake Light to
ensure the parking brake is applied.
EPB Apply
The EPB can be applied anytime
the vehicle is stopped. The EPB is
applied by momentarily lifting up on
the
Yswitch. Once fully applied,
the Electric Parking Brake Light will
be on. While the brake is being
applied, the Electric Parking Brake
Light will flash until full apply is
reached. If the light does not come
on, or remains flashing, have the
vehicle serviced. Do not drive the
vehicle if the Electric Parking Brake
Light is flashing. See your dealer. If the EPB is applied while the
vehicle is in motion, a chime will
sound, and the DIC message
RELEASE PARKING BRAKE will be
displayed. The vehicle will
decelerate as long as the switch is
held in the up position. Releasing
the
Yswitch during the
deceleration will release the parking
brake. If the
Yswitch is held in
the up position until the vehicle
comes to a stop, the EPB will
remain applied.
If the Electric Parking Brake Light
flashes continuously, the EPB is
only partially applied or released,
or there is a problem with the EPB.
The DIC message SERVICE
PARKING BRAKE will be displayed.
If this light flashes continuously,
release the EPB, and attempt to
apply it again. If this light continues
to flash, do not drive the vehicle.
See your dealer.