Chevrolet 2004 Venture Owner's Manual page 53

1. Pick up the latch plate and pull the belt across you.
Don't let it get twisted.
The shoulder belt may lock if you pull the belt
across you very quickly. If this happens, let the belt
go back slightly to unlock it. Then pull the belt
across you more slowly.
2. Push the latch plate into the buckle until it clicks.
In the third row, if the belt stops before it reaches
the buckle, tilt the latch plate and keep pulling
until you can buckle it.
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