Lexus 2003 LS Owner's Manual page 127

Adjusting seat cushion angle and height
16L557
Move the control switch in the desired direction.
Releasing the switch will stop the seat cushion in that position.
COMFORT ADJUSTMENT
Adjusting lumbar support
A Driver's seat (Upper and lower lumbar supports)
To use both lumbar supports effectively, adjust the lower
lumbar support first and then the upper lumbar support.
16L263a

Lower lumbar support
Push the lower lumbar support control switch on either
side.
The amount of lower lumbar support will change while the
switch is pushed.
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