Well, just had an interesting development. Maybe it will result in having to crack open the back and re-seating the battery connector - or maybe not.
I was just using my N7 this AM, knowing that the charge was getting on the low side, like 30%. At 23% my N7 went dead and would not turn on. When I supplied power to it, the screen cycled between displaying very slight static, and then going black. Holding the button down did not matter for the first 2 tries. The 3rd try started up just fine. But I wanted to troubleshoot some more...
So I let it go up to 24% and then I disconnected it from power. Without moving it whatsoever, my N7 went dead at 23% a second time. Since my N7 was not touched/moved during this brief time, I believe this dismisses the loose battery connector idea.
I reconnected power and sure enough, it did not respond to holding down the power button for 30 seconds until the third try. Here's what I think...
- I probably don't have a loose battery connector, given the N7 turning off at a specific power level, without being touched/moved.
- The power circuit/program needs to calibrate itself. The battery appears to be running out of power while the N7 thinks there's still 23% left
- When an N7 turns itself off, it may need up to a minute or so before it wants to respond to the extended power button press - mine did not respond the first or second time - only the 3rd time.
- I'll leave it plugged in well past the 100% charge level today, and I'll run it down to zero and watch the power level that the N7 reports. This may take a few cycles to calibrate.
I welcome your ideas - so give me a shout.
I am sharing my experience here, and will post back in the event what I discover might help other N7 owners.