The other day i decidded to dissamble my NDSi to see if was hard to do the downgrade (and yes, it's). So I decided to mount it again. After putting de screws, i decided to see if it worked, putting the battery (and it worked). When i finished mounting the DSi, i turned it on but nothing happend (very strange). I dissambled again but everything was ok. I saw the plug whic connects the battery with the motherboard and i thought that the problem could be that. When i removed the plug, the plastic pieze which we connect, broken..., (if you need any imagenes just tell me ). At first THE PROBLEM WASN'T THAT because it worked when i turn on the dsi after putting the screws! I decided to solder the two cables to the motherboard, but didn't worked too... So i don't know what's happening... Thanks!