Lexus GS300 1998 Owner's Manual page 186

CAUTION
D After inserting the tab, make sure the tab and buckle are
locked and that the lap and shoulder portions of the belt are
not twisted.
D Do not insert coins, clips, etc. in the buckle as this may
prevent you from properly latching the tab and buckle.
D If the seat belt does not function normally, immediately
contact your Lexus dealer. Do not use the seat until the seat
belt is fixed. It cannot protect your child from injury.
16G047
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
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