Yaris AIR BAG Passenger light - explanation needed

[CTScott]

The "airbag on" should only be lit if there is greater than 80 pounds of human or cargo on the passenger seat. The "airbag off" light illuminates if there is less than 80 pounds (I am not sure what the lower threshold is that turn it on) on the seat. The third light is the passenger seatbelt light. That one should only illuminate when weight is preset, but the seatbelt is not latched.