[Temp Sensor problem - some clarification needed]

Sorry the bed does heat up, but the actual temp display doesn't update.

[Temp Sensor problem - some clarification needed]

I've followed the instruction from here; https://ultimaker.com/en/resources/19484-stopped-temp-sensor following a problem when starting prints of a temp sensor problem. So i've swapped Temp 1 and Temp 3 and heating the bed doesn't bring up an error - but it also doesn't increase the temperature of the bed it stays stuck at 27 degrees. When I then try heating up the nozzle I get bed temperature error.

 

The instructions aren't super clear about this. Does it mean it's the sensors fault or the main board?