GMC 2004 Savana - Manual (Page 144)

Rear Heating System
Your vehicle may have a rear heating system that allows
you to adjust the amount of air flowing into the rear of the
vehicle, from the front-seating area. This feature works
with the main climate-control system in your vehicle.
AUX (Auxiliary Heating System): The thumbwheel for
this system is located to the right of the audio system.
9
(Fan): Turn the thumbwheel up or down to increase
or decrease the amount of heated air sent to the
rear-seating area.
9 (Off): Turn the thumbwheel to this position to turn
off the rear heating system.
Rear Air Conditioning and Heating
System
Your vehicle may have a rear heating and
air-conditioning system. This system regulates the
temperature, the fan speed and the air delivery for the
rear-seat passengers only. It also works with the
main climate-control system in your vehicle.
Use this control panel when you would like to maintain
a separate temperature setting. Adjust the direction
of the airflow or adjust the fan speed for the rear-seat
passenger(s).
Front Climate-Control Panel
3-22