GMC Sierra Denali Owner's Manual page 313

Notice: If the other system isn't a 12-volt system
with a negative ground, both vehicles can be
damaged.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles 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 the automatic
transmission in PARK (P) before setting the parking
brake. If you have a four-wheel-drive vehicle, be
sure the transfer case is in a drive gear not in
NEUTRAL.
Notice: If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
3.
4.
Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or in the accessory power outlets. Turn off
the radio and all the lamps that aren't needed.
This will avoid sparks and help save both batteries.
And it could save your radio!
Open the hoods and locate the positive (+) and
negative (-) terminal locations of the other vehicle.
Your vehicle has a remote positive (+) jump starting
terminal and a remote negative (-) jump starting
terminal. You should always use these remote
terminals instead of the terminals on the battery.
The remote positive (+) terminal is located behind
a red plastic cover near the engine accessory
drive bracket. To uncover the remote positive (+)
terminal, open the red plastic cover.
The remote negative (-) terminal is located on the
engine drive bracket on all V8 and diesel
engines, and on the thermostat housing on the
8.1L engine. On V8 engines it is marked "GND."
See Engine Compartment Overview on page 5-12
for more information on location.
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