Ford Windstar Owner's Manual page 211

Double check the retractor is in the automatic locking mode.
8.
Try to pull more belt out of the retractor. If you cannot, the
belt is in the automatic locking mode. See Figure 8.
Checking the retractor
Check to make sure that the seat is properly secured prior to
9.
each use. If the retractor is not locked, repeat steps 6
through 8.
NOTE: To remove retractor from the automatic lock mode,
allow seat belt to retract fully to its stowed position
and the retractor will automatically switch back to the
vehicle sensitive locking mode for normal adult usage.
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