12v disconnecting periodically

If you read the post here, you'll find that the 12v battery will cause strange things to happen when it gets weak.
How old is it? If it's 6-7 years or older, might be a good idea to replace it.
If it's less than 7 years old, Toyota will replace it, for free. 84 month warranty(7 years).
I just replaced mine, It was 9 years old.

 

Have you tried putting a charge on the battery?

 

Merely looking may not suffice. Check that those terminals are tight. If so, loosen them slightly, then shift the clamps slightly, then retighten.

 

And don't forget the point where the ground cable connects to the car's body.

 

For test of the battery itself: hook up one of the new gen of load testers; it'll read the volts and the Cold Cranking Amps, and deliver a verdict, the battery's "viability". Dealerships have these, but will likely ding you a half-hour's labour. Automotive retail stores often have such testers and will test for free; it's good for business. Or you can pick one up, for somewhere between $50~100.

I'm using a Solar BA5, and I believe it's current iteration is BA9.

 

WHAT? The 12v batter failed? Hard to believe!