Well, I mentioned earlier that when you take it off scan mode and put it into set up, or even the main menu it'll stay on all day long... then the moment it goes into scan mode, or maybe 10-15 seconds at the most, boom, reset city.
Which is the same behavior as if the car is actually off, it'll stay on in set up mode, but once you put it into scan it says "oops car's off..." and shuts down.
That's what made me (and I guess Todd) think it's not a power issue