IOS 4.2.1 battery drain

The solution has been posted countless times in this thread. To keep it simple, restore your iPhone with iTunes, and restore "AS NEW" NOT FROM BACKUP. You will lose app data so think it through. When I upgraded to 4.2.1 the day it came out I noticed the drain. I could watch the battery draining 1% in 5 minutes just sitting there.

After restoring as new my battery yesterday was about 12 hrs usage, 5 hours standby. I streamed movies, listened to music, used GPS. all in one day without charge.

Also, remember that the iPhones battery is only rated at 7 hours. You might also want to disable location apps and ease up on notifications. For mail, set it to manual, NO PUSH.

dbsantos77 wrote:
The solution has been posted countless times in this thread. To keep it simple, restore your iPhone with iTunes, and restore "AS NEW" NOT FROM BACKUP. You will lose app data so think it through. When I upgraded to 4.2.1 the day it came out I noticed the drain. I could watch the battery draining 1% in 5 minutes just sitting there.

Your "solution" isn't really a solution, if it means that I lose my app data! Heck, I'm leery of even trying "reset network settings", for fear of losing wifi passwords that I've accumulated over time. (and considering the premium price and "it just works" motto, I don't think think that Apple should consider that a solution, either)

I had the same issue as an earlier poster, equal usage and standby (and battery dying quickly even with the display locked). It seemed to go away on its own, and 2 weeks later, it's come back on seemingly on its own. No new apps, no settings changed on the phone. The only difference is that I made some changes to the wifi network at my house right before the problem came back.

When the equal usage and standby issue isn't there, my battery life is phenomenal, even with notifications, push email, wifi on, occasional use of gps, bluetooth, etc.

I'm pretty sure Apple changed something with the way that notifications work on wifi, and that's where my bug lies. Here's hoping for a fix on 4.2.2 or 4.3...

Yes, there has been same problem with my iphone as well when I recently updated to the new FW : 4.2.1

I did take it to apple store after checking out the forums and did not find an answer what is causing my battery to drain within couple of hours. And I found out that the Apple store retail guys who called themselves "genius" are actually bunch of " dumb a$$e$ " working there ....so ..
Okie ..enough of story ....

*Solution :* I figured out what was causing the battery to drain
1) The IOS versions higher than 4.0 use something which minimize the apps you used recently and keep on running behind the screen. You can see it by pressing the home button twice and scroll through all the apps that are running and you an close them one by one ...I know that *** ... by clicking on the app ..for 2 sec you will see a red delete symbol appearing over the app thumbnail..

2) IOS versions higher than 4.0 uses the location services differently which tries to refresh your location more often than the previous OS ( do not know exact time )
You have manually switch off the location services by going to Settings -> General -> Location Services - Turn off location services on the all of the apps other than maps or around me whatever is your preference( Least the better ) ..I am using only 2 apps with locations services " on" and my battery is doing great ..2 days before I need to recharge again.

Hope it helps ........:)

dbsantos77 wrote:

After restoring as new my battery yesterday was about 12 hrs usage, 5 hours standby. I streamed movies, listened to music, used GPS. all in one day without charge.

Also, remember that the iPhones battery is only rated at 7 hours. You might also want to disable location apps and ease up on notifications. For mail, set it to manual, NO PUSH.

Curious, why is your usage more than your standby? Or do you mean you used it for 12 hours, and let it stand for 5 before it drained? Apple has said the new lithium battery has a 300 hour standby charge. That's a lot more than the 5 hours you indicated.

Here's what they advertised:

Talk time:
Up to 7 hours on 3G
Up to 14 hours on 2G

Standby time: Up to 300 hours

Internet use:
Up to 6 hours on 3G
Up to 10 hours on Wi-Fi

Video playback: Up to 10 hours

Audio playback: Up to 40 hours

However they didn't advertise that you'll need to turn off certain features, and have to do at least a couple of new restores after updating to each new iOS that comes out. Which doesn't/hasn't helped others here. It's good that some of the tips here are working for others. But don't assume that it WILL help ALL. Because if you read the entire thread, you'll read that the tips don't work for all.

By the way, they aren't solutions, they are workarounds. A solution would mean that the phone works like it's intended to without having to do all these workarounds. Location service is there for a reason, why should one have to turn it off to conserve battery life. Push notification for Mail is there for a reason (all though I never used it because I found it annoying and didn't want to get hit by data charges when I didn't have wi-fi), it shouldn't be one of the causes to drain the battery faster. There are also those that have reported they have RESTORED FROM BACKUP without any issues and their phone is working fine again. Plain and simple there is a flaw in the hardware and software. Who, what, and where is anyone's guess, because not everyone is affected. But there are still those that are, so it is happening.

I think the most viable "solution" is the replacement of the battery. It would seem that the iOS has messed up the battery sensor some how. That the only way to bring the phone back to the original state before the update, is to replace the battery. Some have posted success with this. But not everyone is brave enough to do it themselves, and possibly void their warranty (should they still have it). So there hasn't been very many attempts of this, and being posted.

barry80 wrote:
bro, u're right! i've restore as a new phone for fourth time! still, the usage = standby time never gone! this problem only happen when i upgraded to 4.2.1 last month. this seriously is a bug for 4.2.1. apple should fix it asap...

This happened to me when I upgraded my old 3GS from 3.1.2 to 4.0. 3 iPhone 3GS, restoring two of them from scratch at least twice (that's a royal pain in the arse). After the third 3GS still having issues (both battery drain and rebooting issues), I finally got upgraded to the iP4. Phone has been working great. After reading these posts, as well as in other forums, I won't be updating to 4.2. Made the mistake of updating to 4.0 with the 3GS, don't want to make the same one with the iP4 and 4.2. I can live without extra fonts, ringtones and wifi printing.

The standby time was accumulated after locking the iPhone throughout the day to do other things. Keep in mind I didn't play games hours on end and drain the battery in one shot. I did a multitude of things throughout the day and that's why it's lasted.

Yes, they don't specify that you'll need to shut off services and restore the phone to get the most battery life, but I decided to. When there is a new operating system out, I never do an upgrade. I always backup and format then do a fresh install. I quit running apps that I don't use at the moment or will not use when the iPhone is locked. Not the same method but the same concept, just the way I am with these sort of things.

You're right, it is a workaround as opposed to a solution. However, I rather have a workaround rather than twiddling my thumbs waiting for Apple to make said "solution."

My battery drains 12% after 1 hour use and 2.5 hours standby. Is that normal?

dbsantos77 wrote:
However, I rather have a workaround rather than twiddling my thumbs waiting for Apple to make said "solution."

True, true. They left a lot of us here with no other choice.

clarkkent, my iP4 running on 4.1, from a 100% when I leave for work in the morning (9am) to the time I charge it again when I go to bed (around 1am), my battery only drains down to about 40-45%. That's moderate use, play about 4 games through out the day (not long stints), check FB, listen to music for about a couple of hours, minimal phone conversations, majority of use is texting and internet access including watching YouTube videos. Also daily updates to apps. That's actually pretty good. Which I would assume is what people were getting prior to the update. For you, I would say your numbers are a little less than what you should be getting (more is better). Which is better than what I was experiencing before, and as others have mentioned, where the battery would go down about 1% every couple of minutes...on standby.

Happy New Year!

I bring an update back from page 19. Resetting network settings did not help immediately, but after about ten days (and some more experiments, such as deleting and reinstalling the Facebook app) I finally noticed that my standby battery usage was back to normal (2-3% overnight). Since some people seemed to think that you'd have to wait for a day or two before some actions took effect, I wasn't sure what exactly it was that fixed the problem, but after reading up on the thread, I think that the savior was about three hours of airplane mode, since the improvement happened directly afterwards. Either that, or it was relocating to another country and therefore starting to use another cellular network. I'll have to get back to you on whether the problem resurfaces when I return home in a couple of days.

This makes me think that I was on to something with my original assessment (that the problem has something to do with the cellular network). Although, if a few hours of airplane mode patches the problem for a few days at a time, then turning on airplane mode overnight is an easy fix (unless you have a specific reason why you'd want to be reachable in your sleep). However, it does seem obvious that the problem - and therefore the fix - is not identical for every user, which explains why Apple is having such a hard time finding a quick solution.

Azukikuru

airplane mode haven't try yet. will try out ur "solution" for this miserable 4.2.1 upgrade.

The new profile we downloaded makes my wifi signal weaker all around my house, now, with NO help on battery drainage.

Gonna delete.

The guy at the Genius Bar (partially) resolved the issue yesterday. He pointed out that even though all apps are closed and battery life was declining before our very eyes, that the little icon showing 3G syncing was active about every 10 seconds. The 3GS was trying to syn for no reason, consuming lots of battery and making the unit hot to touch. We switched off the one email account that uses a MS Exchange server (I have a couple of other accounts - POP and Google that we didn't touch). Instant resolution. Now I will have to talk to the IT guy at work to reinstall the Exchange A/C because I don't have all the needed account info. The Apple Techie entered into my account record that if the phone starts having the same problem after reinstalling the Exchange A/C, it will be replaced under warranty.

I have a 3GS and was having similar problems with accelerated battery drain; this was despite changing country/network provider, the phone being in Airplane mode the whole time and doing the cold restart described elsewhere in the thread. I drew the line at performing a factory reset or switching-off Wi-Fi (I didn't want to lose data and still want to use the functionality I paid for!).

What has resolved it for me was installing a number of app upgrades. The only one of these that was running and has regular usage was the Facebook app. It's not a scientific diagnosis, but my money would be on this being the source of my woes.

I can now see that battery performance on the 3GS does seem to have improved on 4.2.1 when compared with the previous version I was running.

many thx to u, azukikuru. since the 4.2.1 upgraded, I havin' trouble seeking the effective solution for the battery draining issue & usage = standby time problem. Read through all the above pages & I can't find any solution that suit my case most except your airplane mode for couples of hours. what I did is switch on airplane mode for three hours as u said, wait it out & turn it off to let the telco's network syn for another hour. & voila, all the problematic issue just gone! seriously, this is totally some kind of bug for this miserable 4.2.1!

APPLE! pls fix it!

I have experienced the battery drain as well after upgrading to 4.2.1 and was able to resolve part of the issue by finally resetting the phone as new via iTunes. This has brought the battery life back to almost what it was before the upgrade.

However, during the nights I experience a substantial loss of battery. I always set my phone on Flight Mode when I get to sleep and when I look at my battery in the morning it has decreased by 15 to 20%. Before the upgrade the decrease was 1% - if at all. Even with closing all multitasking apps over night the loss is the same.

I have tried all of Lawrence Finch's solutions to the problem, even the "reset as new" option and still have the same problem. I would expect the iPhone to cut all connections in flight mode but obviously some process is still running that must be causing the battery drain.

Does anyone have had similar experiences? Any suggestions to solve the problem?