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I'm having trouble rebooting Samsung Galaxy Note 3, where it starts rebooting after holding lock button, but blacks out when/before it reaches lock screen. After blacking out (or before rebooting) it toggles empty charging battery logo in intervals and vibrates in between. As shown in the video here.

I just replaced new battery with the old one and got same behavior. However, when I connected phone to power supply (battery taken out, connected 3.8V straight to the pins), phone boots up perfectly normal and operates normally, as if nothing happened in the first place. This might be worth mentioning; the current supply, mean reboot sequence, can be pretty high (some times, e.g. right before it gets to lock screen, there is a current spike of 1A - 1.5A) but drawn current is lowered few seconds after boot to cca 200 mA and only spikes up (then back down) if any application is opened (that is, if there is action).

So that got me thinking that old battery is incapable of supplying needed current for reboot, but doesn't look like that this is it, since response is the same as in the case of new battery (got original).

EDIT: I just accidentally found out if I short negative pin of battery and another one in between negative and positive pin, while phone is rebooting, it reboots normally, without issues and operates normally further on, even if shorted connection between those two pins is removed. Also am able to reboot it normally from now on and don't need to short those two pins each time on reboot sequence.

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    The third pin which you shorted is usually the battery health pin (see this answer. This pin is used by the OS to monitor the battery status. My guess is that for some reason (dirty terminal? Loose contact?) that was not connected properly, leading the OS to being unable to read the battery health and therefore the symptoms as in video // I suggest cleaning the terminal (light sandpaper) and if the problem persists, use a small strip of aluminum foil folded to make a perfect connection between the third battery pin and the terminal – beeshyams Apr 13 at 11:28
  • @Keno Before you managed to make it work again have you tried to get the battery status as shown by various hardware info apps? Would be really interesting if the shown battery data were looking normal. – Robert Apr 13 at 13:00

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