Hotend giving reading with no thermistor

My hot end just all of a sudden started reading 244C at room temperature. I thought to myself, gee my thermistor must be going bad so I swapped it out and it is still reading 244C. Anybody have a clue what I should be checking? It was working before but when I started my printer today it just showed up like this. I haven't attempted to print or heat the nozzle because I imagine I'd have to set the temp to greater than 244 for it to even attempt to heat up.

Edited 1 time(s). Last edit at 03/09/2016 07:45PM by SteveKing84.

I swapped the thermistor for the bed and the hot end on ramps and the thermistor works fine. But the hot end always reads 244/245C...

Edited 1 time(s). Last edit at 03/09/2016 07:38PM by SteveKing84.

If this is a hardware problem would it be Ramps or the Arduino? I need this printer working so I'll overnight one or both of these parts

Most probably the mega, thermistors only go threw a few discrete components on the ramps

Edited 1 time(s). Last edit at 03/09/2016 09:50PM by Dust.

Thanks, ordered up a mega. Unfortunately won't get it until Friday though.

Problem solved by swapping out the mega board. Thanks guys

Edited 1 time(s). Last edit at 03/11/2016 11:51AM by SteveKing84.