Heatbed temperature copying extruder temperature.
I have a melzi board 2.0 board that was working fine , now I have a problem with BTEMP readings, it is copying the ETEMP readings.
I can turn on and heat the bed and it's working fine but temp won't change it will remain the same around 40 degrees.
When I turn on the extruder, the heatbed temp will read the same values.
Replaced the capacitor and resistor near Btemp pins, problem remains.
I suspect a short somewhere but noob in electronics can't guess where to inspect.
Tried to change Btemp/Etemp sensor pins in the firmware , to X Y Z endstops , heater and bed temps read 350 degrees at rooms temp or when nothing is plugged.
is there a solution for this ? someone told me this Analog to digital conversion issue , would replacing the chip fix this issue ?