Mazda 2008 Mazda3 4-Door Owner's Manual page 27

Essential Safety Equipment
Seat Belt Systems
qAutomatic Locking Mode
Always use the automatic locking mode to keep the child-restraint system from shifting to
an unsafe position in the event of an accident. To enable seat belt automatic locking mode,
pull it all the way out and connect it as instructed on the child-restraint system. It will
retract down to the child-restraint system and stay locked on it. See the section on child
restraint (page 2-25).
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