denisrohr

If you look at https://github.com/bigtreetech/BIGTREETECH-OCTOPUS-V1.0/blob/master/Hardware/BIGTREETECH%20Octopus.pdf you can see the pin "PROBE" on J40 is attached to an optocoupler EL357C with a 1k resistor. The optocoupler has a 1.4V forward voltage...