Chevrolet Express Owner's Manual page 336

If any accessories are left on or
plugged in during the jump
starting procedure, they could be
damaged. The repairs would not
be covered by the vehicle
warranty. Whenever possible, turn
off or unplug all accessories on
either vehicle when jump starting.
3. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
cigarette lighter or the accessory
power outlet. Turn off the radio
and all lamps that are not
needed. This will avoid sparks
and help save both batteries.
And it could save the radio!
4. Open the hoods and locate the
positive (+) and negative ( )
terminal locations of the other
vehicle.
On your van, use the unpainted
radio antenna bracket as a
remote negative ( ) terminal.
Using an open flame 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.
Be sure the battery has enough
water. You do not need to add
water to the battery installed in
your new vehicle. But if a battery
has filler caps, be sure the right
amount of fluid is there. If it is low,
add water to take care of that
first. If you do not, explosive gas
could be present.
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.
Fans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
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