Pontiac 2003 Bonneville Owner's Manual page 307

You will not see the battery of your vehicle under
the hood. It is located under the rear passenger's
seat. You will not need to access the battery
for jump starting. The remote positive (+) terminal
is for that purpose.
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
don't need to add water to the ACDelco@
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 don't, explosive
gas could be present.
Battery fluid contains acid that can burn you.
Don't 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.
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