Cadillac 2011 CTS Coupe Owner's Manual page 430

Your vehicle has a remote
negative ( ) ground location, as
shown in the illustration. It is
located on the left side of the
engine compartment. See
. You should
always use this remote ground
location, instead of the terminal
on the battery.
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 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.