IOS 4.2.1 battery drain

The upgrade for me was better =)

Tej

The Solution for me seems to be, to get rid of find my iphone and turning off the auto on the mail account!

Statistics:
5 h,9 m use; 4 d,5h standby; 9 m talk; 2 mb sent,18,5 mb loaded.
Battery start 100%, now 22%.

Unfortunately, I have an iPhone 3Gs - so there is no "find my iPhone" to deactivate. Disabling push mail does not help either. It has to be something with either the address book or the calender trying to load some data that it could not get from my exchange account.

I just wonder what made it work again when I was abroad using data roaming.

Hello,

I have been having the battery drain problem too since "upgrading" to 4.2... I posted my experiences earlier in this thread. I tried all the different resets and restores, but nothing seemed to help. After reading here (and a couple of different threads) to try turning the Cellular Data to "ON" it seems to have fixed everything.

Here are my stats as of right now:

Battery: 69%
Usage: 1 Hour, 25 Minutes
Standby: 2 Days, 5 Hours

Cellular Network Data Sent: 91.0KB
Cellular Network Data Received: 646KB

This leads me to believe that something in the phone is trying to send data over the network every so often. If it's successful then it doesn't use any more battery power, but if it isn't successfull then it must keep trying and trying which of course will drain the battery.

Now my only question is what data is being transfered and by what? I don't use my phone any differently now than I did with Cell Data turned to "OFF". Obviously, before with Cell Data turned off my Cellular Network Data Sent/Received were always at 0.

Hopefully this will help someone. I went from only getting about a day of use/standby on my battery (since 4.2) to getting back to where I only need to charge my phone a couple of times per week -- just from turning Cellular Data on!


Z

Z ... did you "reset warnings" when you did the last sync?


thx

Go into Settings/Mail, Contacts,Calendar, tap on the Exchange account, and turn off Contacts and Calendar. Then back out to the Settings home screen. Launch calendar, then launch Address Book. The reboot the phone. Go back into settings and turn Contacts and Calendar back on.

No, w7sg, I did not "reset warnings". Why do you ask?


Z

Last night I have disabled only the Calender under Settings -> Mail, Contacts, Calendars -> Accounts -> Exchange and resetted the phone. It did help - the drain over night in airplane mode has stopped and usage and standby times differed again. However, as soon as I switch the Calender back on, I am back with the drain.

I do not want to disable my calender for good, since I need it frequently for work. Seems that I am stuck with the drain then... At least now I know what is causing it.

I had battery draining issues too when i first upgraded to OS 4.2.1 on my ipod touch 2G. I was so disappointed and upset. But then after hours of research, all I had to do was restore the ipod in itunes as a new device (make sure it's as a new device, not from a backup). In other words you should get prompted to enter a name for your device. And that TOTALLY FIXED my battery issue and made it even better than before! Of course doing things like turning push and location off and wifi (when not in use) all help. You know the usual apple tips to preserve battery life won't hurt. But that's what worked for me and I hope it works for others. By the way that fixed my wifi issue too (which was showing me 1 or 2 bars when it should be showing 3).
Oh another thing for the batter issue that someone else suggested was to let the battery drain completely until the device shuts off by itself then fully charge. They said this should recaliberate the battery with the new OS and make it work better with it (supposedly), but i haven't tried that yet. But then again I don't need to now! Good luck to all.

I upgraded my iPhone 4 to iOS 4.1.2 at 23:00, January 29. The current time is 14:52 on January 31st. The statistics right now are:
Battery 74%
Usage: 2h 13m
Standby: 1 Day, 16 hours
-
So as you can see, it is working just fine for me and I did not lose any data. All I did after upgrading was that I went into the list of apps running in the background (which, it turns out, is every single one of them when you upgrade) and closed them by tapping the little red minus sign.
I don't talk much on the phone but do check my mail, Bloomberg and news regularly. It seems my phone will easily last until tomorrow evening, which makes it four days of battery time.
Cheers.

Now THIS is interesting:

First time I noticed the problem was early Dec and it got fixed on Dec. 13 per my post at the time in this thread. No problems ever since until yesterday:

Traveling from Germany to London I turned phone into airplane mode during the flight. Back on the ground turned it off again and took the Heathrow Express into London, then the tube to my destination - altogether maybe 45min. When I pulled the phone out to take a picture it was quite hot and the Battery was significant lower than at the time when I left the plane.

As I had my eTicket for train and plane on the iPhone I was scared to run out of battery during the day and not get home as I could not present the required barcode on the phone at check-in. So I turned the phone off most of the day (no phone, no pictures, no iPod, no Navigation, no Web nor emails - all the good things of the iPhone during travel I could not use...).

Just turned it on every couple of hours to check for missed calls and email. Every time the phone got hot again quickly - so the problem remained as expected even after power off/on. Also tried airplane mode again w/o success either.



Now here comes the interesting part:

As soon as I arrived back Germany and turned the phone out of airplane mode it is running normal again??? Almost no battery drain all night.



Needless to say that this is VERY disturbing as the iPhone is especially on business travel a great piece of equipment, but it MUST BE RELIABLE. Can't imagine the trouble one ends up in when the phone is flat and one finds only out at the security check when they ask for the boarding pass. This will almost guarantee to miss the flight because of this stupid bug!

Message was edited by: 850T5

I was experiencing the same when I went to Austria: Phone went hot and battery lasted only two or three hours (see my posts earlier in this thread). What immediately fixed the problem was to turn on data roaming. The phone downloaded only a few Kb and the drain stopped immediately.

Might help you next time round!

Maybe you should just delete the account and recreate it. There's something wrong with that Exchange account.

I've had the Airplane mode battery drain problem too, but after I quit all the background tasks and restarted the phone, all is well. Many apps get updated regularly, and this resolves issues that may have been lurking for a while. Apps need to be compatible with the lasts iPhone firmware.

Been there, done that. No effect. I resetted the phone, set it up as new and installed the exchange account anew. Nothing helped. I finally found out that it was the calendar that was causing the drain.

What finally helped was as described by Lawrence Finch above: disable the calendar under Settings -> Mail, contacts,... -> exchange account -> calendar. Start the calendar so the phone knows it is disabled. Restart the phone and enable the calendar. I did this about four times and now my phone is back to behaving normal.

Hi guys, same problem here in my 3gs.
I have to say two things:
Alpha) when the battery drain syndrome has started, when you try to volume up or down during call, the screen is flickering.
Beta) since I removed google, foursquare, facebook & insragram, after restart, the syndrome stopped.(didn't remove exchange account, push notifications off)
Hope these help, greetings from Greece.