Cadillac 2005 CTS Owner's Manual page 66

If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint
following the child restraint manufacturer's directions
and refer to Securing a Child Restraint in the Right
Front Seat Position on page 1-44 .
If after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle's seatback is not pressing the
child restraint into the seat cushion. If this happens,
slightly recline the vehicle's seatback and adjust the
seat cushion if possible. Also make sure the child
restraint is not trapped under the vehicle head restraint.
If this happens, adjust the head restraint.
If the on indicator is still lit, secure the child in the
child restraint in a rear seat position in the vehicle and
check with your dealer.
The passenger sensing system is designed to
enable (may inflate) the right front passenger's frontal
airbag anytime the system senses that a person of
adult size is sitting properly in the right front passenger's
seat. When the passenger sensing system has
allowed the airbag to be enabled, the on indicator will
light and stay lit to remind you that the airbag is active.
1-60
For some children who have outgrown child restraints
and for very small adults, the passenger sensing system
may or may not turn off the right front passenger's
frontal airbag, depending upon the person's seating
posture and body build. Everyone in your vehicle who
has outgrown child restraints should wear a safety
belt properly — whether or not there is an airbag for
that person.
If a person of adult-size is sitting in the right front
passenger's seat, but the off indicator is lit, it could be
because that person is not sitting properly in the seat.
If this happens, turn the vehicle off and ask the person to
place the seatback in the fully upright position, then
sit upright in the seat, centered on the seat cushion,
with the person's legs comfortably extended. Restart the
vehicle and have the person remain in this position
for about two minutes. This will allow the system
to detect that person and then enable the passenger's
airbag.