Lexus RX 450h 2010 Owner's Manual page 149

1-8. Safety information
STEP 3
STEP 4
STEP 5
If the child restraint has a top tether strap, the top tether strap
STEP 6
should be latched onto the top tether strap anchor. (→P. 150)
148
Run the seat belt through the child
restraint system and insert the
plate into the buckle. Make sure
that the belt is not twisted.
Fully extend the shoulder belt and
allow it to retract to put it in lock
mode. In lock mode, the belt can-
not be extended.
While pushing the child restraint
system into the rear seat, allow the
shoulder belt to retract until the
child restraint system is securely in
place.
After the shoulder belt has
retracted to a point where there is
no slack in the belt, pull the belt to
check that it cannot be extended.