I sent in my old 3DS to Nintendo for repairs because of loose hinges. Nintendo replaced my 3DS when they sent it back. So what I've started noticing is that while I'm in the middle of a game, or if I put my 3DS on a table, the system goes into sleep mode without me closing the top screen. I'm puzzled by this and after I move it around for a few seconds, it turns back on. This is starting to get a bit annoying, so I'm wondering if there is anything I can do, or if I need to go send it back again.
As far as I know there is no auto sleep on the 3DS so no I wouldnt think this is a normal function. I would call nintendo support to see if they have any other problems known to them like this. unless the power saver mode is on you might want to check and see if it is. If it is turn it off
I agree. It seems like the mechanism that determines whether the device is open or closed is malfunctioning. You would have to send it to Nintendo to be repaired. I'm sure you already know, but their number is 1-800-255-3700.
Apperently there is a hidden feature with your 3DS it will go into sleep mode even while open if placed next to a DSi while the DSi is turned on and in sleep mode I do not know if this is true but i read it in a thread titled Hidden abilities. if you own a DSi or a friend/family member does and it is in sleep mode that might be what is happening I will include the link to the thread that I am talking about. it is the last post made by ANTWHAT that I was reading. but like I said I have no clue if this actually true or jsut a rumor.