Chevrolet 2003 Astro Owner's Manual page 267

The other end of the negative (-) cable does not
go to the dead battery. It goes to a heavy,
unpainted metal engine part, or to a remote
negative (-) terminal on the vehicle with the
dead battery.
Notice:
Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly. To prevent electrical shorting, take care
that the cables don't touch each other
or
any
other metal. The repairs wouldn't be covered by
your warranty.
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