Lincoln 2010 MKZ - Manual (Page 122)

To lower the seatback(s), pull the
release handle(s) located inside the
trunk.
Fold the seatback(s) down.
WARNING: Before returning the seatback to its original
position, make sure that cargo or any objects are not trapped
behind the seatback. After returning the seatback to its original
position, pull on the seatback to ensure that it has fully latched. An
unlatched seat may become dangerous in the event of a sudden stop or
collision.
Make sure that the safety belt for the rear center passenger is properly
routed over the rear seatback.
Seating and Safety Restraints
122
2010 MKZ (378)
Owners Guide, 3rd Printing
USA (fus)