LA130 -- Blades stopped while mowing

Greetings. I've found great help here before so I'm back and trying again.

I was mowing...

The RIO button was working and then it wouldn't. Minutes later, the blades simply stopped spinning as if I disengaged by using the button.

Any ideas for trouble-shooting?

I pulled the PTO and the connectors look fine. Same with the RIO.

I've tried to find a wiring diagram so I can test the switches but my google-fu isn't up to the task.

Suggestions?

Anyone?

Point me in a direction or something?

Pretty please?