GMC 2007 Sierra 1500 Pickup Owner's Manual page 251

Never put a child in a rear-facing child restraint in
the right front passenger seat the unless
passenger airbag status indicator shows off. Never
put a rear facing child restraint in the right front
passenger seat unless the airbag is off. Here
is why:
CAUTION:
{
Even though the passenger sensing
system is designed to turn off the
passenger's frontal airbag if the system
detects a rear-facing child restraint, no
system is fail-safe, and no one can
guarantee that an airbag will not deploy
under some unusual circumstance, even
though it is turned off. We recommend
that rear-facing child restraints be
transported in vehicles with a rear seat
that will accommodate a rear-facing child
restraint, whenever possible.
If the word ON or the on symbol is lit on the
passenger airbag status indicator, it means that
the right front passenger's frontal airbag is enabled
(may inflate).
CAUTION:
{
If the on indicator comes on when you have
a rear-facing child restraint installed in the
right front passenger's seat, it means that
the passenger sensing system has not
turned off the passenger's frontal airbag.
A child in a rear-facing child restraint can
be seriously injured or killed if the right
front passenger's airbag inflates. This is
because the back of the rear-facing child
restraint would be very close to the
inflating airbag. Do not use a rear-facing
child restraint in the right front passenger's
seat if the airbag is turned on.
251