Honda Civic Owner's Manual page 62

uuChild SafetyuSafety of Infants and Small Children
60
6. Make sure the child seat is firmly secured by
rocking it forward and back and side to
side; little movement should be felt.
7. Make sure any unused seat belt that a child
can reach is buckled, the lockable retractor
is activated, and the belt is fully retracted
and locked.
1Installing a Child Seat with a Seat Belt
To deactivate a lockable retractor, release the buckle
and allow the seat belt to wind up all the way.