I'm on a Huxley with a Melzi Ardentissimo, with a Reprap hotbed.

The sensor was working fine, it suddenly started to report off base value of around 200C.
Now each time it's powered on, the temperature is different, though always between 160 and 200.

A short-circuit might have provoke the problem.

Is there any way to reset or tune it's temperature measurement?

How can I check if the component is OK?

cheers

Measure the resistance of the thermistor after unplugging it from the controller. The most common ones are 100 or 10 kohms at 25C. Lower resistance would be read as high temperature by the controller. If you measure a low resistance, check for possible shorts in the leads.

Edited 1 time(s). Last edit at 03/09/2013 08:51AM by brnrd.

Thanks brnrd, I came to understand a Thermistor is a resistance, and I had a short.
I couldn't identify it, but opening the wood - PCB - Aluminum sandwitch was enough to get rid of it...

Lesson learnt, hopefully!