LCD Showing 371.2 Hot End Temp

[JohnStack]

Had just a little problem, not really sure what.

Latest board (b), latest firmware (repetier), calibrated the hot end (4650 was my beta setting)

Had some stringing on a print so I homed and turned off and back on.
Turn on the fan to 25% to accelerate cooling to recheck calibration and if the tube inside the hot end wasn't mucked up
Left it on for 3 hours
Came back, head temp was 371.2/0

Disconnected hot end, thermistor lead had broken (not sure if it was the result of me pulling the hot end off or not)

Turned back on Rockstock, head temp still 371.2/0 without thermistor connected, so it is the board.
Tried reloading firmware just in case there was a glitch somewhere, nope.

What can I replace? I've had blown fuses, can't be a blown fuse or it would read 0, correct? Next up: Try changing extruder from 0 to 1. Question: Which pins? Which area in Pins.H

(There are a few posts about blown boards, replacing fuses, I did not see on a search anything about replacing specific parts - or perhaps my search terms were not correct but related is here:

http://forum.seemecnc.com/viewtopic.php?t=1757&p=11068

specifically http://forum.seemecnc.com/viewtopic.php ... t&start=10
)

So what if I wanted to change pin settings for Repetier Firmware (latest sometime in April) to try the other hot end circuit? The last link above only has it for Marlin.

[Polygonhell]

You either have a short/broken connection with the thermistor, or you've damaged the input on the RAMBO board.
Ideally check the resistance with a meter first, but if you disconnect the 12V power and plug the hotend thermistor into the bed thermistor port, does it read correctly.

[JohnStack]

GREAT SUGGESTION!!! Missed that one when I was looking around!!!

I'll rebuild my hot end, check tonight and let you know. I pulled it apart since it wasn't reading any resistance - indicating a dead thermistor / broken wire...

I have never seen the display go to 371/0 though - when the HE circuit wasn't plugged in (heat or thermistor).