Pontiac 2003 Montana Owner's Manual page 208

Setting the Temperature
If the driver is adjusting the temperature, do the
following:
To increase or decrease the temperature for the entire
vehicle, use the temperature controls located on the
main climate-control panel.
If using the main climate-control panel, then the
air-conditioning system must be on to direct cooled air
to the rear of the vehicle. If it is not on, then the
temperature in the rear of the vehicle will remain at
cabin temperature.
If a rear-seat passenger is adjusting the temperature, do
the following:
Press the TEMP button on the rear control panel. Use
the left arrow button to make the air cooler. Use the right
arrow button to make the air warmer.
Rear Air Outlets
To increase airflow through the rear floor outlets, place
the left bucket seat in the second row in the forward
position. For more information, see "Seats" in the Index.
The outlet behind the left rear seat is the cold air
return outlet. Be sure to keep it free from obstructions.
Also, keep the area around the base of the center
instrument panel console, between and under the front
seats, free of objects that could also obstruct airflow
to the rear-seating area.
For more information on how to use the main climate
control system, see "Climate Controls" listed previously
in this section. For information on ventilation, see
"Outlet Adjustment" also listed previously in this section.
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