Unresolved Arduino board problem?

Hi, guys. I previously had a short at the clip connector to the arduino board, and it seemed to be fixed after a new heated bed and replacement of the clip. Two days ago, however, I started having new problems. A print failed midway with the following error:

->N303589 G1 X104.045 Y95.138 E5838.39077*88 [16971.577]
<-Error:Extruder switched off. Temperature fell too much during print! [16971.611]
<-Errorrinter stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) [16971.615]

It was similar to the error I had when my thermistor wasn't keeping good connection with the extruder but I have since replaced it with a screw-on type. And checking the temperature of the extruder with a reboot showed that the temperature did not drop enough to abort extruding.

I rechecked all connections and tried again but now, the printer goes through the calibration routine and then just stops with the following error:

->N23 G0 F9000 X145.65 Y99.893 Z0.3*32 [245.321]
<-Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) [245.331]

While the printer is going through the calibration, the extruder temp is only intermittenly updated. I always preheat before printing and during preheat time, the temp is updated real time.

I've always had some intermittent unexplained print failures I chalked off to having bad USB connection so I had a Smart LCD XXL on order and I installed it, and it would boot up but any attempt to control the printer results in gargage characters filling the screen.

I'm uploading 4 pictures. The first two are of the clip and the connector points on the board, showing scorch marks from the short. My guess is that the two leads from the wire weren't tightly screwed in and were loose. The third and fourth pics are of the SMART LCD XXL, right after bootup and a few seconds later.

Is this indicative of a faulty board? Perhaps I should have pressed for the replacement of the board after the first short but at that time, it seemed everything was working fine. The Robo3D people asked me to swap the clip of the extruder to the bed connector and it was supplying enough juice to heat up the extruder and we thought it was fine.

 

That doesn't look good. You should contact robo's tech support on that.

 

Tech support recommended that I make a parts request for a new board. I'll update it when I receive and install it.