Lexus LX 470 1998 Owner's Manual page 138

16X113a
2. Fully extend the shoulder belt to put it in the lock mode. When
the belt is then retracted slightly, it cannot be extended.
To hold the convertible seat securely, make sure the belt is in the lock
mode before letting the belt to retract.
COMFORT ADJUSTMENT
16X114a
3. While pressing the convertible seat firmly against the seat
cushion and seatback, let the shoulder belt retract as far as it will go
to hold the convertible seat securely.
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