1999 Chevrolet Corvette Owner's Manual - Page 172

yellowblue A/C: This button turns the air conditioning compressor on or off, except in the FRONT defrost mode. The light on the A/C button will come on when the compressor is operating in either the automatic or manual mode. The air conditioning may also be forced off at high engine speeds. The light on the A/C button will flash if pressed when air conditioning operation is not allowed. FRESH AIR: Press this button to provide fresh air from the outside. The light on this air intake button will come on to show when it is operating. When in the AUTO mode, the system automatically selects FRESH AIR instead of recirculate, as required, to control the temperature in the vehicle. By pressing FRESH AIR, the system will lock into the fresh air mode. Any adjustment to the air intake must then be made manually. FRESH AIR should be used when trying to defrost or defog windows to help reduce moisture inside the vehicle. RECIRCULATE: Press this button to limit the amount of fresh air entering the vehicle. The light on this air intake button will come on to show when it is operating. Recirculate is helpful when you are trying to cool the air quickly or trying to limit odors and dust from entering the vehicle. When in the AUTO mode, the system automatically selects recirculate to cool the vehicle's temperature. By pressing this button, the system will lock into the recirculated air mode. Any adjustment to the air intake must then be made manually. The recirculated air mode is not allowed in the front defrost or defog modes as fresh air helps reduce moisture inside the vehicle. FRONT: Press the FRONT defrost button to quickly remove fog or frost from the windshield. This setting directs most of the airflow to the windshield and a small amount toward the lower and side window outlets. The light on the button will come on and the digital display will show the defrost mode symbol and fan speed when the front defrost mode is being used. Pressing FRONT defrost again will return the system to the last operating mode. 3-8