2008 won't turn off

Got this 08 in Florida in March with 105k, drove it cross country to Washington, so have put almost 6k on it with no problems. I love this car.

Last night I started up after dark and my low beams wouldn't come on. I drove home with high beams. All other lights are fine. Same this morning when I checked.

Perhaps unrelated to headlights, today when I started it all the dash lights, speedo, gear indicator, odo, etc, would not come on but it ran fine. This happened 4 or 5 days ago and then went back to normal an hour later. I drove 3 miles and shut it off. Also, while on the highway the cruise control would not work. Started it up 20 minutes later, still no dash lights. The monitor was not affected. Drove home and backed into my yard. The back up camera did not come on though the screen was on. Put it in park, hit the power button, and..... Nothing Happened! Tried several times. It would not shut off. Monitor stayed on and the engine would start and stop as it usually would. I pulled forward a few feet and backed up, then tried the power button again and it shut off. Then I started it again and no dash lights or back up camera and it wouldn't shut off. Also the back hatch wouldn't unlock.

Thinking of taking it to the dealer, I took everything out of the back hatch to reach interior release. As soon as I opened the hatch the dash lights came on. Now it is all functioning normally but I'm getting a little paranoid. I can live without a speedometer or back up camera, but I need it to be able to shut it off. I've turned it on and off a few times and it is normal. So no use taking it to a mechanic if it won't misbehave.

So I'm wondering if it happens again if it would be ok to disconnect the battery terminal under the hood as I suppose that would shut everything down.
Could be moisture somewhere? It was a misty day here yesterday.

Thanks for any ideas. This is my first Prius and I hope to keep it going another 100k. I appreciate this forum and have learned a lot reading old threads.

 

Brand new AGM

 

Thanks for the answers. I'll research combo meter repair. Had not heard of that before.