Buick LaCrosse Owner's Manual page 13

See
.
To raise or recline the seatback, tilt
the top of the vertical control
forward or rearward. See
.
To adjust the lumbar support,
if available:
Press and hold the front or rear
of the control to increase or
decrease lumbar support.
Press and hold the top or bottom
of the control to raise or lower
lumbar support.
See
.
If available, the MEM, 1, and 2
buttons on the outboard side of the
driver seat are used to manually
save and recall the driver seat and
outside mirror positions. These
manually stored positions are
referred to as Button Memory
positions.