electrical problems

Gday guys looking for some good old knowledge on a 2388 , 3 days ago my father was harvesting along and the separator seemed to drop in and out of gear not mechanical it seems to be electrical because when this started I put my multimeter on and it will cut in and out of power from 0v to 12.5v...

I'm having trouble with one of my height sensors not working on my Case Ih 4430. It will show a height but it appears to be off and it won't engage. I can get the other side to work and I've concluded it's not the sensor as I've swapped the sensors around and they work on the other side...