You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

💡 Did you know?

⏺ If you can't accept iCloud Terms and Conditions... Learn more >

⏺ If you don't see your iCloud notes in the Notes app... Learn more >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

FIX FOR: iPhone 4 battery draining fast, phone running hot

I had the same issue many have reported here and in comments on blogs, where their +_battery was draining at least twice as fast_+ as on an iPhone 3GS with iOS 4.

Some threads suggest +_this happens to iPhone 4 when restored from a 3G or 3GS_+, and indeed, that's what I'd done. A few people said that resetting to factory settings and installing everything fresh solved the issue, giving them better battery life than they'd seen on any prior iPhone.

Many of my apps have files or settings stored in them, so I didn't want to have to set everything up again. A fresh install is a real pain.

Deep in an iPhone 3G thread mentioning a similar battery problem after upgrading to iOS 4, someone said they'd deleted all their mail accounts, and set those up fresh, which solved the issue for them. I tried that today, and it worked.

*_BEFORE AND AFTER_*:

Thursday and Friday, the iPhone 4 went from 100% to 15% in under 6 hours. Today, after this fix, the iPhone 4 is at 87% after 12 hours. Thursday and Friday the phone was hot to the touch whenever I picked it up. Today it's always cool. Apps usage and movement among coverage areas on each day have been exactly the same. The only change was resetting up mail.

*_STEPS TO FIX_*:

Do this on WiFi so you can sync and check mail fast.

1. Delete all mail accounts.

2. If MobileMe user, delete MobileMe account, and remove all Calendars, Contacts, Notes, etc., from the phone (so you don't have dupes when you re-sync).

3. Turn off phone, and back on again.

4. If MobileMe user, add MobileMe account first. I enabled all options, even Find My iPhone (Thursday and Friday I had it off, in case it was using power). Wait long enough for contacts and calendars to sync, check to make sure. I use MobileMe mail on Push.

5. Add back each additional mail account. I have 5. I am in a marginal coverage area, so I set these accounts on Fetch Hourly. I also have "Preview 5 Lines" (I think the default is Preview 2 Lines. This doesn't matter.)

6. Go into Mail, go to the MobileMe Inbox, and scroll your way down letting the messages come in. You can see them come in when you see the Preview Lines update, and then scroll some more.

7. Go into each additional mail account's Inbox, scroll your way down, letting the messages come in.

8. Go to the combined Inbox if you use that, make sure all the messages are in.

9. The WiFi activity spinner may remain spinning even after Mail says it is done Checking Mail. This is because other parts of mail accounts are being synced for the first time. Let the iPhone sit in Mail combined inbox until the spinner stops. Quit Mail, go back in, and watch the spinner after it's done Checking Mail. If the spinner doesn't stop after < 5 seconds or so, let Mail sit again. Once it's caught up, going into mail will Check Mail, and the spinner will stop a few seconds after as it should.

10. You're done.

Hopefully your phone stays cool and your battery life reflects the boost from the 20% larger battery. If not, the next step to try is Reset Network Settings, and finally try a factory reset and installing everything fresh instead of doing a restore. Hopefully you won't need to do that. I didn't.

(a) G5 Quad; (b) Mac Pro; (c) MBP 17"; (d) iMac 24"; (e) iPhone, Mac OS X (10.6.1), (a) 6.5 GB, Apple 30" + Cintiq 21; (b) 4 GB, Dell 30" + Samsung 215TW

Posted on Jun 26, 2010 5:53 PM

Reply
317 replies

Nov 25, 2012 4:41 PM in response to mhg8

mhg8 wrote:


how can battery drain not disappear for me when i use no email account?

Because email is not the only app that uses battery power?


There are 500 thousand apps available for the iPhone. All of them use some power, and some of them use a lot of power. Any that connect to the Internet use power, and that's probably over half of them. If your battery is draining faster than you think it should based on the specs for the phone (http://www.apple.com/iphone/specs.html) start by reviewing your apps.


But, as you haven't said how much drain you are experiencing or even what model you have we have no way of knowing whether it is in the normal range or not.

Nov 27, 2012 11:21 PM in response to Lawrence Finch

i just had the weirdest thing happen to me today. i've had my iphone 4 for exactly 2 years now. i left it last night with 80% battery, slept for 8 hours, woke up to find it at 35%. wifi was off, no programs were running except for: calendar, messages, settings, skype. there were no notifications at all.

my normal battery drain during night time is between 5% and 7%. i have never had a 50% drop! but i usually don't leave skype running. the phone is running the latest ios (which i think is 6.1)

this happened to me once only on ios 5, but i had left teh phone for 6 hours in a poor reception area. however laast night it was at home, which is notmally a good reception area.

my question is: could this have been skype running, or is it possible that i had lost signal at some point and the phone was searching all night? and if so, should this drain 50%?

is there a solution or a way of finding out what's wrong?

Nov 28, 2012 6:20 AM in response to mira_ishak

And you didn't even update it, but you have sudden battery drain.


This problem has been discussed pretty much continuously for the past 5 1/2 years. I did a tabulation a few months ago and found over 20,000 posts about it. Which is still small compared to 300 million iOS devices, but it is the most commonly discussed problem in these forums and other iPhone venues on the Internet. Many of those 20,000 posts have useful information that I don't want to repeat, but the root cause is usually an app on your phone that got stuck in a loop trying to send data and failing.


Rebooting sometimes helps.


As the app is frequently mail deleting a mail account, rebooting, and adding it back will sometimes cure it.


Sometimes it cures itself.


Sometimes running the battery down until the phone shuts off, then charging with the wall charger for 4 hours fixes it (and also recalibrates the battery gauge).


Turning off all data (cellular and wifi) can sometimes CAUSE the problem, because not all apps check to make sure there's a connection before sending. If this is the problem turning data back on will fix it.


best of luck finding the recalcitrant application.

Nov 28, 2012 6:45 AM in response to Lawrence Finch

thank you very much Lawrence Finch

for your very useful information. i was pancicing that i have some sort of damage, although i keep my phone very well maintained!


in my case, teh only app that was running was Skype. i had wifi off but 3G on. however, the phone was inside my bag and there was another bag on top of it, so maybe that casue a poor reception and casued the phone to keep searching!


jsut as a side note, i charge my phone every 2 days, but i charge it during the night when i am asleep. i leave it to charge all night. someone mentioned that it shouldn't be left to charge all night, cuz this might damage the battery. is this true?


i also hardly ever drain teh battery to empty. so this time i will try to do that. then charge a full cycle.

Nov 28, 2012 7:11 AM in response to mira_ishak

mira_ishak wrote:


thank you very much Lawrence Finch


jsut as a side note, i charge my phone every 2 days, but i charge it during the night when i am asleep. i leave it to charge all night. someone mentioned that it shouldn't be left to charge all night, cuz this might damage the battery. is this true?

No, there is a smart charger in the phone. The external "charger" is actually just a dumb power source. The charging circuit fast charges to 80%, then slow charges to 100%, then shuts off. So you can leave it plugged in forever without hurting the battery. One apparently odd symptom results from this process: Once the charger has turned off the phone is using battery power exclusively. So if there are background processes running the battery will start to discharge. If it goes below about 95% the charger will come back on to top it off. But if you look at the phone in the morning after it has been charging all night occasionally it will not be at full charge; perhaps somewhere between 96% and 99%.



i also hardly ever drain teh battery to empty. so this time i will try to do that. then charge a full cycle.

Apple recommends doing this about once a month. The purpose is to recalibrate the battery gauge. Lithium chemistry batteries maintain a constant voltage across their discharge cycle, so you can't tell the state of charge by monitoring voltage. Instead the battery circuit monitors usage, tracking energy in and energy out to determine the state of charge. This proces is imprecise, however, so errors creep in slowly. A full discharge (which isn't really a full discharge, because the phone shuts off with some energy remaining in the battery) followed by a full charge gives the battery monitor markers for empty and full so it can correct the drift in the monitored data.

FIX FOR: iPhone 4 battery draining fast, phone running hot

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.