I am 100% positive I am using a 4-20 mA signal on 4.0, 4.1, 4.2, 4.3, 5.0, and 5.1, as I am using these in SUB instructions, so unsure why it is not showing up as "used". Probably some fault in the software. This is why I thought maybe since there is no W next to 5.2 and 5.3, those channels are more than likely open. There is slim chance something is actually plugged in, since there is no logic for those in the plc program.