GMC Yukon XL Denali Owner's Manual page 61

The buttons are on the front doors.
(Cooled Seat): Press to cool
the seat.
(Heated Seatback): Press to
heat the seatback only.
(Heated Seat and Seatback):
Press to heat the seat and
seatback.
Press the button once for the
highest setting. With each press of
the button, the seat will change to
the next lower setting, and then to
the off setting. The lights indicate
three for the highest setting and one
for the lowest.
The passenger seat may take
longer to heat up.
The heated and cooled seats are
canceled when the ignition is turned
off. To use this feature after
restarting the vehicle, press the
desired button again.
Seats and Restraints
Remote Start Heated Seats
When it is cold outside, the heated
seats may turn on automatically
during a remote vehicle start. The
heated seats will be canceled when
the ignition is turned on. Press the
desired button to use the heated
seats after the vehicle is started.
The lights on the heated seat
buttons do not turn on during a
remote start.
The temperature performance of an
unoccupied seat may be reduced.
This is normal.
See Remote Vehicle Start on
page 2 5.
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