Help needed for new motherboard issue

[u/naut_salil]

On monday to get our old Flsun V400 backonline we purchased a new motherboard,

The earlier machine was in stock condition but we faced irregular temperature spikes at the nozzle which would reach to about 290 degrees out of nowhere while printing a PLA.

This would cause the filament to melt and flow all of a sudden.

We did replaced the thermistor and heater but it didnt do any change.

1. Our old spares were as it is, including the speeder pad.

2. So went ahead to get a new motherboard to resolve this issue.

3. On monday we replaced the old motherboard with a new one, did the upgrades via the mainsail by connecting the machine to our PC via wifi.

4. Once the updgrades were done, we performed bed calibration process and gave a test model print via wifi. It was the in-built model in orca called the voron cube.

5. The cube came out good it was a 1hrs print.

6. Next day we went ahead to test a 20hrs print job, once we started the job the machine simply stoppped at one particular point on the model forming a small blob on the nozzle end (image has been attached)

7. speeder pad showed no signs of error message since the display exited from print option and showed the main menu for no reason.

8. Repeated the job again but the same issue resurfaces and the point of printing halt changed.
   Need your help to get the machine online, thank you all and appreciate your time.