I have a John Deere D140 I have had for around 5-7 years. It's been great. Last year I started to notice when I turned the key I got nothing on the start sometimes No click. Nothing. Like a dead battery. Not even lights. I check battery and all fine. I noticed that when I hard shut on/off the PTO for the blades I could then get it to start. Then I was cutting grass and all of the sudden the blades stopped but tractor ran right in the middle of cutting. I took tractor to garage and shut down and then we are back to will not start. Thinking it's PTO I replace it. Still no joy. This wreaks of pure electrical issue but not sure where to look next? Any thoughts? Fuse? Wiring somewhere?