Recirculation Button

When the fresh/recirculated air switch is pressed, the switch connects a ground to the BC1. The BC1 then grounds the indicator LED in the switch and the recirculated air side of the fresh/recirculation air servomotor. The indicator LED illuminates and the fresh/recirculation air servomotor moves the control flap in the filter housing to close the fresh air inlet and open the recirculated air inlet.