Hummer 2006 H3 Owner's Manual page 68

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.
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