This happened to me today. Here's what I found. I lifted the cover to suck up my sweepings. When I closed it, the vacuum stayed running. Upon investigating, I found the round cap covering the hole has two tabs or ears located at the top. These tabs slide into a slot inside the outer square cover. It seems the tabs came out of the slots so when the cover was closed, it failed to make connection and didn't shut off the motor. I reinstalled the cap tabs into the slots and fixed it. I'll get pictures when I return home. We're camping so I'm kinda busy. Fishing, hot tub, napping, eating, etc.
2013 Palomino Columbus 320RS
2007 Dodge RAM 2500 6.7 Cummins
Reese 15K manual slider
M.I.L. in Florida for good!!