iPhone 5 dies at 30% since iOS 7

I'm glad you "know" it is a software bug, but it has nothing to do with 7.0. My phone has done the same with 6.x and with 5.x. Any iPhone will do the same thing on any version if the battery monitor calibration gets confused.

To fix it you need to recalibrate the battery gauge. When the phone shuts off above 1% charge it for about a minute, just enough to get it to come back on. Then use it until it shuts off again. If it shuts off above 1%, repeat the process until you get to 1% and it shuts off. Usually this takes me 2 or 3 tries.

Once it shuts off and will not restart charge it for 4 hours with the wall charger. This should fix the problem. To prevent it from happening again run the battery all the way down then charge for 4 hours about once a month.

It's definitely a bug, but not a new one. Which leads me to suspect its a bug in the battery monitor hardware, which is why it survives all updates. Apple's battery help articles (for all products) suggest running the battery all the way down periodically, but they don't say why. I think this is why.

I'm not too hard on them about it, because Lithium chemistry batteries are very difficult to monitor. Their output voltage does not drop measurably until they are almost out of charge. So the battery monitor cannot monitor voltage the way you can for a car battery, but must keep track of the energy in and the energy out to determine when it needs to be charged. The measurement isn't perfect, so eventually it will lose track of what the actual charge is. Recharging from "empty" allows it to reset.

Striker37, I agree with you. I have had every single iPhone released and never had this problem before. My iPhone 5 does this as well since the update and it's driving me nuts. Yesterday it did it at 34% and would turn on a few minutes later with same percentage then shut right back off. Every time I get the 20% notification it shuts off shortly after.

nfosdick wrote:

Striker37, I agree with you. I have had every single iPhone released and never had this problem before. My iPhone 5 does this as well since the update and it's driving me nuts. Yesterday it did it at 34% and would turn on a few minutes later with same percentage then shut right back off. Every time I get the 20% notification it shuts off shortly after.

I haven't had every iPhone released; only the original, 3GS, 4S and now a 5S. I have had this problem with each of them except the 5S, and I easily fixed it each time it happened. You can read how I fixed it in the 2nd post. I'm sure you can fix it also.

I Read the whole discussion before I posted. I understand you say this fixes it but it is strange that this problem never once happened with my phone until the update. I plan on trying your suggestion today.

I Did your suggestion the other day and it worked for 48 hours and now I am back to it doing the same thing again with today being the worst. I had 47% battery life and it died once, then twice and I had to plug it in to keep it on 😟

You probably have a bad battery, then. Take it to an Apple store and they can test it.

I've seen a lot of posts about this problem all across these forums and the rest of the Internet. There is a lot of speculation about running battery-draining apps and replacing the battery on your phone. Usually, that's all I'd find for a problem like this.

Your solution addressed the problem exactly, was accurate down to the minute details (i.e. taking 2-3 tries to get it down to 1%), and worked. At least for now. I'll see if the problem comes back again in a few days. Thank you very much, sir.

my iphone dies WAAAAYYYY befor it even gets that low....... i have an iphone 5 that i bought from a friend and it has the 7.1 software on it........ i need help and quickly....... is there any way of getting rid of this problem?? i can see others talkin about letting it die but this is something i have to use everyday and almost all day cuz of business. i can't have it dying on me in the middle of an online conversation whether it b whatsapp and or skype. i need it done right away

Message was edited by: Bahamian Guy

I'm experiencing the same issue on a pre-owned iPhone 5 I just picked up to replace the one that was just stolen from me. I have owned just about every iPhone since initial launch (2G, 3G, 4S and two 5's) and never experienced this issue before. It always seems to shut off between 30-40%, long before ever getting a low battery warning. It just shut off at 37% about 20 minutes ago and I'm not trying what was suggested to recalibrate the battery meter, I let it charge for about 60 seconds and disconnected the charger. I'm down to 32% as I type this so fingers crossed this helps after 2-3 times. Wish me luck!

Very belated update. I went through the whole process of charging the battery down until it dies, then plugging it back in to give it a little more juice, then repeating until it got down to 0% before charging it all the way for four hours.

I tried that about 2-3 times. It actually made my battery worse. It never made it past 40% after I did that.

Ultimately, I just bit the bullet, took it to Genius Bar, and bought a new battery for $75 or whatever it was. Haven't had any problems since then.