re: John Deere X360 lawn tractor wiring harness question.

Hi
I worked on many JD tractors big and small over the years.
One of the biggest issues is what’s called a “floating ground”
Somewhere on your equipment it’s making an intermittent contact to the frame where you should have a good negative ground from the battery negative terminal.
Many times paint from the factory that is sprayed on he frame first will cause this problem.
I would trace the negative terminal from the battery and where it connects to the frame or metal, remove it, sand down to bare metal, reconnect the negative cable coming from the battery, should be good to go.