Buick LaCrosse Owner's Manual page 434

This post (A) is used instead of a
direct connection to the battery.
1. Check the other vehicle. It must
have a 12-volt battery with a
negative ground system.
2. Position the two vehicles so that
they are not touching.
3. Set the parking brake firmly and
put the shift lever in P (Park).
See
.
4. Turn the ignition to LOCK/OFF
and switch off all lights and
accessories in both vehicles,
except the hazard warning
flashers if needed.
An electric fan 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.
Using a match 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,
(Continued)