Lexus RX300 Manual page 90

Adjusting lumbar support (driver's seat only)
16R005b
Push the control switch on either side.
The amount of lumbar support will change as long as the switch is
pushed.
COMFORT ADJUSTMENT
Flattening seatbacks
16R100
Before flattening seatbacks, slide the rear seats as far back as
possible.
1 Push the seat position control switch forward to move the seat
forward.
2
Push the seat position control switch upward to raise the seat
(driver's seat only).
3 Push the lock release button on the head restraint to remove it.
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