ADC Out Of Range - Strange Issue

Hello, I have a very strange issue on a V-Core 4 I have. Everything is working fine. Just the extruder temperature sensor is out of range. When I start the printer reports a shutdown due to the extruder temp out of range (see photo). At first I thought okay that must be due to the thermistor, maybe its broken. So I tested another one, same issue. Even the value is 100% the same whats strange. I tested it without a thermistor connected, same value. So I switched out the EBB42. Same issue. Then I switched to a new Octopus Board. Same issue. I flashed RatOS completely new. Same issue. I am running out of ideas. I tried switching the type of thermistor from PT1000 to others in the list, just to see what would happen. The value switched but for example to -198 or something like that. Can someone help me with that? What could I try? Thanks and best regards!