GMC 1996 Sierra Owner's Manual page 219

2.
Get the vehicles close enough so the jumper cables
can reach, but be sure the ve.hicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake firmly on both vehicles
involved in the jump start procedure. Put an
automatic transmission in PARK
(P)
or a manual
transmission in NEUTRAL (N). If you have a
four-wheel-drive vehicle, be sure the transfer
case is not in NEUTRAL (N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets, if you have this
option. Turn off all lamps that aren't needed as well
as radios. This will avoid sparks and help save both
batteries. In addition,
it
could save your radio!
NOTICE:
I ~~~ ~
If
you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
4. Open the hoods and locate the batteries. Find
the positive
(+)
and negative
(-)
terminals
0 1 1
each battery.
A
CAUTION:
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools away from
any underhood electric fan.
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