GMC Sierra 2005 Owner's Manual page 65

To remove the child restraint, just unbuckle the vehicle's
safety belt and let it go back all the way. The safety
belt will move freely again and be ready to work for an
adult or larger child passenger.
If you had turned the airbag off with the switch,
remember to be sure to use the airbag off switch to turn
on the right front passenger's airbag when you remove
the child restraint from the vehicle unless the person
who will be sitting there is a member of a passenger
airbag risk group. See Airbag Off Switch on page 1-71.
CAUTION:
{
If the right front passenger's airbag is turned
off for a person who is not in a risk group
identified by the national government, that
person will not have the extra protection of an
airbag. In a crash, the airbag will not be able
to inflate and help protect the person sitting
there. Do not turn off the passenger's airbag
unless the person sitting there is in a risk
group. See Airbag Off Switch on page 1-71 for
more on this, including important safety
information.
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