Chevrolet 2011 Volt Owner's Manual page 446

If the Volt won't start, the 12 volt
battery may be run down. To jump
start the Volt use the underhood
remote positive (+) and negative ( )
terminals.
1. The other vehicle used to jump
start the Volt must have a 12 volt
battery with a negative ground
system.
2. Park both vehicles close enough
so that the jumper cables can
reach both vehicles' positive (+)
and negative ( ) terminals.
The vehicles must not touch
each other. It could cause an
unwanted ground connection
that could damage both vehicles'
electrical systems.
Put both vehicles in P (Park) for
an automatic transmission or
electric drive unit. For a manual
transmission, place the vehicle
in N (Neutral) and set the
parking brake.
3. Turn off the ignition on the
other vehicle. Turn off the radio,
all lamps, and accessories that
are not needed in both vehicles.
Unplug accessories from the
cigarette lighter or the accessory
power outlets. This avoids
sparks and helps save both
batteries and accessories.
4. Locate the positive (+) and
negative ( ) terminals on the
other vehicle.
5. Open the hood to locate the
positive (+) and negative ( )
terminals on your Volt. Open the
access cover (A) for the remote
positive (+) terminal. The remote
negative terminal (B) for the Volt
is a stud marked GND ( ) on
the driver side of the engine
compartment.