UMO thermistor reading limited

[markusa380 0]

Recently, the readings of the thermistor on my UMO are limited.

A completely cold printhead will show ~120°C, when heating up this value does not change until the printhead actually reaches ~120°C.

Then the temperature readings seem to be accurate within a margin of error.

This all wouldn't be a problem, if the printer wouldn't abort heating before the printhead reached said thereshold.

Of course the first thought is about a defect component, so I replaced:

• The thermistor
• The thermocouple
• The Ultiboard
• The Arduino

I also checked the cables, of course.

On the new arduino I flashed a customized fork of the Marlin firmware available on GitHub, forked from the Marlin_UM_HeatedBedUpgrade branch.

Here's the link to my repo: https://github.com/MarkusA380/Marlin

What could be the problem?