Well I know this is a long time after the original post but incase someone else reads this – here's what I think it is and why. I believe the issue is with the battery indicator light connection or cable which is located to the right next to the battery connector on the motherboard. I can't confirm it just yet because I need a new battery light indicator unit after accidently snapping the cable connector whist putting my machine back together after replacing my keyboard. I suspect this indicator unit also functions as to tell the computer that the lid is closed (I'm guessing magnetically). So either the connector beside the battery on the motherboard is not attached properly or is damaged. I'll know for sure after replacing broken indicator unit.