3GS - incredibly poor battery life

I got 89% after 1 hr, brightness test. Btw you guys off the auto-brightness?

Yes, the Auto Brightness should be OFF. If left ON the screen brightness is automatically adjusted with regard to the outside light conditions which would make the test results incomparable.

Another update, good participation. I'm not going to post the iPod test results since it hasn't changed.

*Brightness Test:*
Graphics Bong: 1hr = 90% -- 2hr = 78%
ThisIsANewID: 2hr = 75%, 2hr(test 2) = 76%
sidssp: 1hr = 90%
allen009: 1hr = 90% -- 2hr = 77% (he did a second 1 hour test with same result)
glassrabbit: 1hr = 75% (should have better results with the new phone! please let us know)
mac girl122: 1hr = 89%
Tekksas: 1hr = 89% -- 2hr = 76%
noney82: 1hr = 84%
lookn4wifi: 1hr = 91% -- 2hr = 77%
mikkec: 1hr = 89% -- 2hr = 77%
SpurtSpanker: 1hr = 90% (he did the test twice with same result)
DrPerf: 1hr = 91%
javaTN: 1hr = 89% (he posted detailed percentage decreases for the hour)
tntrieu: 1hr = 91%

So far the results are pretty consistent with 1hr average at 90% and 2hr average at 77%. The second hour is more convincing as the battery is in that "drop off" zone. A 3rd hour would be interesting, I haven't been able to commit the time yet.

I decided to run your brightness run down test and have an interesting result that doesn't fit nicely into your table. As you suggested, I set my iPhone up in Airplane mode at full brightness and Auto dim off. I checked the battery level every 5 minutes. I saw a decline of approximately 3 percentage points every 5 minutes until it hit 77% at 45 minutes. When I checked at 50 minutes a surprising thing happened. The fuel guage now reported 91% up from 77% at the previous reading. From there it declined to 88% by the end of the first hour. I am still running the test to see where it ends up after two hours.

I know that I get awful battery life during normal use and something is definitely wrong with the phone and/or software. However, I think that we are also dealing with an inaccurate fuel gauge and that is adding to the general confusion.

How long have you had the phone for, merctp? Have you tried calibrating the battery a few times? Charge it all the way up to 100%, and use it like crazy until the phone dies (turns off by itself). Afterwards, charge it back up to 100% without using it much, if at all. After doing that a few times, the meter should be reading normally.

Others, including me, have seen jumps in the indicator, yours sounds pretty extreme though. Try to reproduce the incident by doing another test if you have time, you might get a different charge result too.

I had all these same issues.

Downloaded the 3.0 iPhone update and reinstalled and now I get 3+ days worth of battery life and no heat issues.

I've had the phone for about 2 weeks and have used it quite a bit. Including running the battery down til it was very low. Yesterday, I took the drastic step of restoring the phone to the factory state and setting it up as a new phone instead of restoring from backup. I'm not sure yet whether that has helped, but the battery life is much worse than with either my original iPhone or the 3G. I always made it at least a full day without a charge (unless I played videos or games) with the 3G and with the 3GS, I am fortunate to make it half a day.

Did another brightness test. This time for 2 hours. First hour still got 90%, second hour down to 75%.

So starting today something weird happened. At 5pm I had 45% battery life and went all the way down to 20% by 7:30pm. Before this my battery would last all day from when I wake up to go to sleep which is around 16-17 hours. This just started to happen today and am very confused because I have not installed any apps or doing anything new that is battery intensive.

Sounds like you had a stuck app running in the background. That's quite possible, especially if this is the first time it's happened. If you find this issue arising again, power your phone off and then turn it back on. See if there's any difference. Normally apps shouldn't run in the background (besides phone, mail, and iPod), but with software, sometimes things happen.

I bought my iPhone 3GS a couple of weeks ago. During this time I've been following this thread and doing my own tests. My wife also bough a new iPhone 3G so I've compared both.

I've not done any accurate measurements and my conclusions are based on different kinds of use during this days.

The first day I was scared to see my battery drop 40% in a few hours without doing extremelly heavy usage. So I started doing different things like browsing with WiFi, playing some games, phone calling, having push and notifications on or off, location on or off, using maps with GPS...

I read that many people say that having push on uses lots of battery. Not my case as I've managet to use the iPhone almos for 3 days with push on and normal use. The counter was about 2 days 3 hours standby and about 5 hours use. This for me is ok and I'm happy with it.

But yesterday tryed something different... Turn 3G on! Without 3G on after 100% charge I can have 3 or 4 hours standby befoure falling to 99%. I noticed that something was going wrong when 15 minutes after the full chars my counter was at 94%!!!

Now it's 6 hours standby and 1:52h. use and I'm at 65% with very light use (no browsing, no maps, no location...). It's clear that it's impossible to have a full day use at this rate.

Comparing it to my wife 3G shows that battery drain when doing heavy task (maps+gps, wifi browsing, youtube videos...) are similar on both 3GS and 3G. But when turning 3G on in the 3GS it seems to drain battery in standby as it was doing some heavy task.

So my conclusion is that the battery is ok, as I can use without 3G for 3 days with average use. But there's some hardware or software bug that cause a big battery drain with 3G on!

I can understand why the iPhone uses so much energy to use 3G network. I've previously had an HTC with 3G on all the time and battery last for 4-5 days without problems. Other 3G phones I've own not even had an option to turn 3G off and I can use them for days too.

Regards!

Now I'm totally convinced there's a problem with my iPhone 3GS. After full charging my 3GS and my wife 3G we turned them on and leave home about 8:30AM.

We did some light use (looking settings, she did some Facebook check and a couple of mails) most of the time stand-by and 3 or 4 short phone calls. My wife called me so both phones had same phone talk time.

We came back for lunch at 14:00PM. My 3GS was at 45% and I was shocked when I looked at my wife 3G and the battery meter was totally FULL. It doesn't have the percentage indicator but it did not dropped a pixel! So for sure it was over 90% charge. Here is were I definetily saw there's a problem.

Now it's 4:20PM and I have 27% remaining without even use it. All time standby!

For me it's clear that activating 3G is causing a big drain problem that is not normal on my 3GS.

I'm starting to think that the "S" on the new 3GS stands for "S"hort battery. 😟

Dreamboy wrote:
I'm starting to think that the "S" on the new 3GS stands for "S"hort battery. 😟

I thought that the 3GS was being advertised as having better battery life than the 3G?

Thanks allen099, I think that worked.