I have a ramps/arduino combo that is not working right per this thread.
http://3dprintboard.com/showthread.php?9397-ABL-problem-beckdac-marlin-branch-Roxy-improvements-Y-axis-not-moving-during-G29

Any way to test an arduino for diagnosis of issues? or isolate the issue to the ramps portion? board appears to flash and works right some of the time.