GMC 1999 Sierra 1500 Pickup Owner's Manual page 246

Pmbkms on the Road
not be able to get enough power from a single battery in another vehicle
to start your diesel engine.
If your vehicle has more than one battery, use the battery that's closest
to the starter-this will reduce electrical resistance.
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.
You could be injured if the vehicles roll. Set the parking brake firmly
manual transmission in N (Neutral).
If you have a four-wheel-drive vehicle, be sure the transfer case is
not in N (Neutral).
1
on each vehicle. Put an automatic transmission in P (Park) or a
3. Turn off the ignition on both vehicles. Turn off all lights that aren't need-
ed, and radios. This will avoid sparks and help save both batteries. And
it could save your radio!
ou leave your radio on, it could be badly damaged. The repairs
r.,Jldn't be covered by your warranty.
I
4. Open the hoods and locate the batteries.
Find the positive
(t)
and negative (-) terminals on each battery.
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