outcome is laser sit there changed sboard to mini gerbl and she dont work too ,someone tell could be optical sensors ,now want to switch to mechanical (have these loads) but got dlp printer so that is fun these days 
Thanks for responding. I know exactly what you mean I have a lcd resin printer, less calibration compared to dlp and it’s hard to keep up with so many things. If you’re having homing issues it should give an error. did you try toggling limit switch polarity change $5 from 1 to 0 or vice versa. Or add a software filter by setting $26 to 250 (debounce).