1. hrostami's Avatar
    I have the iPhone 3G with version 3.1.2 and baseband 05.13.04.

    For some reason, when the battery drops to 40% or even 50%, and the phone passcode lock has been opened prior to, it acts as if I had used the "slide to power off" function. The Springboard disappears, the spinning busy icon appears in the middle of a black screen, and then the screen goes out. To turn the phone on again, I have to connect it to a charger (or a computer) and let it turn on. Why does it do this, and how can I prevent it from happening?

    (Note: this doesn't happen if the passcode lock has not been opened. In other words, if it remains locked up, it won't die. The issue is that if I am outside and have to unlock it to make a quick phone call, there is a good chance that it will die instantaneously, right there.)

    Not sure how exactly it was jailbroken; I got it off eBay. I know for sure that it is unlocked by using redsn0w.
    2011-06-04 08:05 PM
  2. Jahooba's Avatar
    Sounds like it has a bad battery. The phone is detecting very little power in the battery so it's shutting itself down.

    Either that, or there's some mod that is causing an error. I'm thinking this is the problem.

    Does this happen every time you unlock it, or only sometimes?
    2011-06-04 09:33 PM
  3. hrostami's Avatar
    Well, around 1/3 of the time, this happens if I unlock it and it is at 50% or 40%.
    2011-06-05 05:49 PM
  4. Jahooba's Avatar
    Hmm, may be the battery. If it was a mod that was crashing, then your phone would simply crash to a black screen, I believe. If you're getting the spinning wheel, that means that it's powering down.

    Batteries for the 3G are pretty cheap now that the iPhone 4 is out. You may want to check out a parts store like this one

    iPod, iPhone Replacement Touch Glass & LCD Screens, iPhone Repair Parts, High Capacity Batteries, BlackBerry, HTC, Tablet Parts

    That's one of the problems about buying used phones: the battery has a recharge limit before it needs to be replaced.
    2011-06-05 06:04 PM
  5. hrostami's Avatar
    What I don't understand is why the phone chooses to power down at 40% because the battery is weak. If it was happening at juice levels as low as 10% or even 15%, I might think of a battery in need of replacement. But it powers down, again, at 40 and even 50% levels, so I'm not so sure that it is in fact the battery that needs to be replaced.
    2011-06-06 02:26 AM
  6. Jahooba's Avatar
    Batteries decay over time. Your iPhone seems to be confused as to how much battery life it has left, because the battery is broken. My mom's iPod shows 100% battery, then skips down to 73%, then 43%, and in weird intervals. That's just what happens when the battery wears out; the iPhone gets confused because it thinks it has half a battery left but the power just isn't there.

    It has something to do with the crystalline structure in the battery. It turns from a liquid to a crystal as the chemicals interact, outputting a trickle of electricity. The chemical reaction back and forth from liquid to crystal only happens so many times before the crystal won't turn back into a liquid, so you can't charge it as much.

    Eventually you're just left with an empty, dried-up battery that won't hold a charge.

    That's my understanding of it, anyway.
    2011-06-06 02:50 AM
  7. hrostami's Avatar
    Jahooba, the condition of the battery should not dictate how the device responds to it aside from shortening its between-charge life. In other words, if the battery is worn out as you say, the phone should at least stay on until the battery's charge is completely used up, and not before, regardless of how worn it is. This is a phenomenon I have never observed before on any device that runs on some sort of battery. I understand that you are trying to help me, and I'm not trying to offend you, but if the iPhone is being "confused", so to speak, then I am a purple flying monkey. That is the only way I can convey my frustration on the issue.


    You know what, maybe I'll just ditch Apple and this BS (again, no offense meant to you here and I do appreciate your help). Get me a nice MyTouch, you know? Nice UI, a battery that will actually stay alive (and is easy to replace, don't forget that!), no need for memory hogging "proprietary" software such as iTunes just to get stuff to and off the phone (which by the way is in itself a huge roadblock to doing these tasks), third-party app support (.apk) and application multitasking right out of the box, easily upgradeable memory that doesn't require purchasing an entirely new device every time you run out of space, MP3 ringtones, and a browser that can download files and find text on a page, among other neat features. The only things I really need to back up from my iPhone are (a) contacts, which are already up on iDrive Lite and which is available on Android Market, and (b) photos, which I can get to via Windows Explorer without the need to launch iTunes. Admittedly, there will be features I will miss, like a dedicated 3.5mm earphone jack, and a greater variety in input languages. But what the heck, the benefits of switching sure outweigh the negative effects.

    By the way, when I decide to get rid of this iPhone, will it be enough to do a hard reset from the phone settings to erase everything, or must I restore and then re-jailbreak and re-unlock?
    Last edited by hrostami; 2011-06-07 at 12:57 AM.
    2011-06-07 12:54 AM
  8. Jahooba's Avatar
    You're simply wrong.

    • The iPhone is not some perfect omnipotent machine with self-awareness, it gets confused to its battery percentage all the time.
    • The iPhone shuts down BEFORE the battery reaches absolutely 0%. That's just how it works.
    • Do what you will, I'm not here to convince you to stick with Apple. You obviously have something wrong with your used, second-hand phone, the likely culprit of which is the battery.
    • If you didn't want/ need help, then why did you ask for it? Perhaps you should find a different website where people like it when you're rude to them?
    • Watch those slipstreams, my purple friend
    2011-06-07 02:43 AM