Unit cranks and runs fine. When I let out on clutch it will die. Disconnect interlock after cranking & it continues to run fine. But try to engage PTO switch & it dies or cuts off as grounding out. I thought it was the seat switch but my volt/ohmn meter seems to say its working. The whole problem seems to be a grounding problem, but I'm not the best at reading a schematic. Any suggestions would be appreciated.