GMC Sierra 2015 Owner's Manual page 459

10-92 Vehicle Care
Warning
Using a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.
Warning
Fans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
6. Check that the jumper cables do
not have loose or missing
insulation. If they do, you could
get a shock. The vehicles could
be damaged too.
Before you connect the cables,
here are some basic things you
should know. Positive (+) will go
to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative ( )
will go to a heavy, unpainted
metal engine part or to a remote
negative ( ) terminal if the
vehicle has one.
Do not connect positive (+) to
negative ( ) or you will get a
short that would damage the
battery and maybe other parts
too. And do not connect the
negative ( ) cable to the
negative ( ) terminal on the
dead battery because this can
cause sparks.
5.3L Shown, 4.3L, 6.0L, 6.2L and
6.6L Similar
7. Connect the red positive (+)
cable to the positive (+) terminal
of the vehicle with the dead
battery.
8. Do not let the other end touch
metal. Connect it to the
positive (+) terminal of the good
battery. Use a remote
positive (+) terminal if the
vehicle has one.