2004 Hyundai Sonata Owner's Manual - Page 79

FEATURES OF YOUR HYUNDAI B670C01O-AAT 1- 67 Air Intake Control NOTE: o It should be noted that prolonged operation of the heating system in " " mode will give rise to fogging of the windshield and side windows and the air within the passenger compartment will become stale. In addition prolonged use of the air conditioning with the " " mode selected may result in the air within the passenger compartment becoming excessively dry. o When the ignition switch is turned "ON" the air intake control will change to " " mode in floor, floor-defrost and defrost position. This is normal operation. But, the air intake control switch will change to " " mode when the ignition switch is turned "ON" with the MAX A/C mode selected. This is normal operation. B675C01Y-AAT MAX A/C switch HEF-037A HEF-037B This is used to select fresh outside air or recirculation inside air. Fresh Recirculation With the " " mode selected, air enters the vehicle from outside and is heated or cooled according to the other functions selected. With the " " mode selected, air from within the passenger compartment is drawn through the heating system and heated or cooled according to the other functions selected. The MAX A/C mode is used to cool the inside of the vehicle faster. If the "MAX A/C" mode is selected. the A/C will turn on automatically and " " mode will be activated and air is discharged the face level vents. NOTE: When you change to another mode from MAX A/C, the A/C and the air intake control switch are set to the following chart.