2005 Chevrolet Astro Owner's Manual - Page 138

Rear Air Conditioning System Your vehicle may have a rear air conditioning system that allows you to adjust the fan speed in the rear seating area, from the front seating area. This feature works with the main climate control system in your vehicle. Turn the thumbwheel up or down to increase or decrease the amount of cooled air sent to the rear seating area. To direct the airflow to the rear seating area, use the right knob located on the main climate control panel. Generally the upper outlets are used for air conditioning and the floor outlets are used for heating. 9 (Fan): The thumbwheel for this system is located to the right of the controls for the climate control system. Move the thumbwheel up or down to HIGH, MED (Medium) or LOW to increase or decrease the fan speed in the rear seating area. Move the thumbwheel to OFF to turn off the fan. 3-22