why is my galaxy note 4 shutting down at 40% power but when you turn it on it shows its not dead

[AC Question]

but when you turn it on it shows its not dead

 

[belodion]

A faulty battery, perhaps.

 

[immobile]

Today I just started having that same problem with my Note 4. It happened right after foolishly downloading this "network booster" . I've done a partition cache wipe before so with the charger plugged in it brought into the boot mode, or whatever you call it, then I did another wipe, don't know if i needed to but I confirmed it, selected reboot and it came back to normal. But if and when I would unplug it started with the reboot dance. Then I put in a fresh battery and had no problems. Until it hit a bit over 40%. So I don't think it was that app, not that I'm going to read download it so I think it's the batter. It used to do it at a little over 20% but all of a sudden it started with this. I might do a factory reset to see if that helps plus clean the terminal connections on the batteries with first like a pencil eraser then maybe alcohol. My Laser on my Ruger lc9 was going out so I disassembled it to change out the batteries and first I tried cleaning them like I said and put them back in and is was brighter than ever. But anyways I think it's a battery and or the charging system in the phone. I sure wish that Note 7 worked out...

 

[belodion]

Does it persist in Safe Mode? Worth a try perhaps.
Less likely, but possible perhaps....a bad SD card?
Both unlikely I think but difficult to see what it could be.

 

[immobile]

Today I just started having that same problem with my Note 4. It happened right after foolishly downloading this "network booster" . I've done a partition cache wipe before so with the charger plugged in it brought into the boot mode, or whatever you call it, then I did another wipe, don't know if i needed to but I confirmed it, selected reboot and it came back to normal. But if and when I would unplug it started with the reboot dance. Then I put in a fresh battery and had no problems. Until it hit a bit over 40%. So I don't think it was that app, not that I'm going to read download it so I think it's the batter. It used to do it at a little over 20% but all of a sudden it started with this. I might do a factory reset to see if that helps plus clean the terminal connections on the batteries with first like a pencil eraser then maybe alcohol. My Laser on my Ruger lc9 was going out so I disassembled it to change out the batteries and first I tried cleaning them like I said and put them back in and is was brighter than ever. But anyways I think it's a battery and or the charging system in the phone. I sure wish that Note 7 worked out...

Both batteries were doing it. One @40% and the second at Full charge, but stayed on until I unplugged the charger then good night , it started the reboot dance. Did a factory reset and all's O.K. now. Ya might want to try that providing your still having the problem. Good luck