Toyota Lexusc Owner's Handbook Manual page 262

D Do not insert coins, clips, etc. in the buckle as this
may prevent your child from properly latching the tab
and buckle.
D If the seat belt does not function normally, it cannot
protect your child from death or serious injury.
Contact your Lexus dealer immediately.
install the child restraint system on the seat until the
seat belt is fixed.
Do not
OCCUPANT RESTRAINT SYSTEMS
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