Lexus RX400h2006 Owner's Manual page 196

4 Move the seatback angle control switch backward to
flatten the seatback.
OCCUPANT RESTRAINT SYSTEMS
5 Push the seat position control switch downward.
After returning the seat to its original position, be certain to
replace the head restraint.
CAUTION
D Do not allow passengers to ride on the flattened seat
while driving; use the seat in the normal position.
D After putting back the seat, try pushing the seatback
forward and rearward to make sure it is secured in
place. Be certain to replace the head restraint.
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