Toyota Highlander Service Manual page 31

Fastening the seat belt (for the third center seat)
Take the plate out of the holder,
1
and then pull down the seat
belt.
Push plate "A" into buckle "A"
2
until a click sound is heard.
Push plate "B" into buckle "B"
3
until a click sound is heard.
HIGHLANDER_U (OM0E017U)
1-1. For safe use
Plate "A"
Buckle "A"
Plate "B"
Buckle "B"
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