Cadillac 1999 DeVille Owner's Manual page 10

Heated Front Seat (Option)
The control is located on the outboard side of each front
seat. Move the SEAT HEAT control to either LO or HI
to turn on the heating elements in the seat. The LO
setting warms the seatback and cushion until the seat
approximates body temperature. The HI setting heats the
seat to a slightly higher temperature. A telltale light in
the control reminds you that the heating system is in use.
The heated seats can only be used when the ignition is
turned on.
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Reclining Front Seatbacks
Press the recliner control, located on the front doors,
forward or rearward to adjust the seatback.
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