GMC 2009 Sierra 1500 Crew Cab Owner's Manual page 93

If the On Indicator is Lit for a Child
Restraint
If a child restraint has been installed and the on
indicator is lit:
1. Turn the vehicle off.
2. Remove the child restraint from the vehicle.
3. Remove any additional items from the seat such as
blankets, cushions, seat covers, seat heaters, or
seat massagers.
4. Reinstall the child restraint following the directions
provided by the child restraint manufacturer and refer
to Securing a Child Restraint in the Right Front Seat
Position With Passenger Sensing System in the
Index.
5. If, after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, turn the vehicle
off. Then slightly recline the vehicle seatback and
adjust the seat cushion, if adjustable, to make sure
that the vehicle seatback is not pushing the child
restraint into the seat cushion.
Also make sure the child restraint is not trapped
under the vehicle head restraint. If this happens,
adjust the head restraint. See Head Restraints
on page 1-3.
6. Restart the vehicle.
The passenger sensing system may or may not turn
off the airbag for a child in a child restraint depending
upon the child's seating posture and body build. It is
better to secure the child restraint in a rear seat.
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