@fillngraves @NilartPax @andyryan1988 As is shown below, there is a tiny switch inside the inlet, which you can call it filament switch. We do not recommend users to disassemble the machine and that will void the limited warranty. I just show what is that switch is there.
As I said before, you can if the switch is on by using command M119.
But if it is caused by some physical issue, like the filament switch is loosened, you can poke the inlet port with the filament to loosen the spring of the sensor and restore it to its original position.
In addition, according to @NilartPax, the function works sometimes, but fails sometimes, that may be some issue related to the firmware.
In a word, we will arrange a test to dig it up in a few days.
