Onan 8000 Generator

Had a similar problem ans eventually found a corroded connector if I remember correctly 5 or 6 pin above the axle on the right side of the generator. I sliced around it and all is good. This start and stop circuit works a little different as the switches do not provide power the the gen start circuit or stop but instead provide a ground for relays.
Hope this helps; Keith

Common complaint and as mentioned there are plugs along the outside that come apart and can often simply be exercised and lubed. WD40 works well. Some have had to bypass the plug as mentioned too.

Do more research and you can find the pinouts and apply your own ground to see if it is internal to the generator or just the plug.

Some day I will build and sell a simple plug in test switch. Not today though,

IF it turns out it is internal to the generator you can parallel the switch on the generator itself.