GMC 2010 Acadia Owner's Manual page 120

3-66 Seats and Restraints
5. Pull the rest of the shoulder belt
all the way out of the retractor to
set the lock.
6. To tighten the belt, push down
on the child restraint, pull the
shoulder portion of the belt to
tighten the lap portion of the belt
and feed the shoulder belt back
into the retractor. When installing
a forward-facing child restraint,
it may be helpful to use your
knee to push down on the child
restraint as you tighten the belt.
7. Push and pull the child restraint
in different directions to be sure
it is secure.
If the airbags are off, the off
indicator in the passenger airbag
status indicator will come on and
stay on when the vehicle is started.
If a child restraint has been
installed and the on indicator is lit,
see If the On Indicator is Lit for a
Child Restraint under Passenger
Sensing System on page 3 39 for
more information.
To remove the child restraint,
unbuckle the vehicle safety belt and
let it return to the stowed position.