Toyota 2009 Tundra Owner's Manual page 182

Regular Cab and Double Cab models: If the child restraint has
a top tether strap, the top tether strap should be latched onto
the top tether strap anchor.
(→P. 156, 158)
Booster seat
n
1-7. Safety information
Fully extend the shoulder belt
and then allow it to retract
slightly in order to activate the
ALR lock mode.
Lock mode allows the seat belt to
retract only.
While pushing the child seat into
the seat, allow the shoulder belt
to retract until the child seat is
securely in place.
After the shoulder
retracted to a point where there is
no slack in the belt, pull the belt to
check that it cannot be extended.
Place the booster seat on the
seat facing the front of the vehi-
cle.
1
belt has
155