Should the Xmin/Ymin/Zmin indicators on the Diagnosis screen stay lit?

I am diagnosing some homing issues with my printer.

For the Xmin/Ymin/Zmin indicators on the Diagnosis screen, if the limit switches are not depressed, we expect these indicators to remain lit continuously, correct? On this screen for my printer, the indicators will flicker off every few seconds. If this is unusual behavior, I expect I have a wiring issue or something wrong with a controller board. If this is normal, perhaps there is something else.



The problem with homing and the indicators flickering appears to be electrical line noise. I rebuilt the mainboard firmware with the ENDSTOP_NOISE_FILTER configuration turned on, and this has fixed the problem for now. I have some 100nF capacitors ordered to fix the noise problem directly, so until those arrive I’ll be running the modified firmware. Thanks again!