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Fix Rapid Battery Drain Problems on the iPhone and iPad

Synopsis:

If the battery on your iPhone or iPad seems to run down much faster than it should, then you may have run into a rapid battery power drain problem. Learn how to fix this problem here.

Let's Begin:

If you own an Apple iPhone, iPad or iPod Touch, you may have noticed that every once in awhile your device’s battery will rapidly discard and drain much faster than it normally does. You may have tried charging it back to full capacity only to find that the battery quickly runs down again, sometimes burning off the full charge in only an hour or so, even when the device is idle and you’re not using. So what’s going on here?

The answer is that it’s caused by a bug in the software on the phone (or other Apple i-device). It may be caused by a bug in an application you downloaded or in the iOS operating system itself. Bugs that cause rapid power drain on your iPhone’s battery are not unique to Apple products. Far from it actually. Any smart phone, or other battery powered portable device, is susceptible to rapid battery drain problems. To understand what’s happening, we have to learn a little bit about power management on modern portable devices:

To maximize battery life, all smart phones actively manage the power used by the device based upon what it’s called on to do at any given instant. ┬áSome of the these power management responses are very familiar to us: things like shutting off the display if there’s no user input within the last few minutes. Other types of power management within the device are not generally visible to the user and are handled automatically by the device’s operating system. This includes shutting down unused sections of the electronics in the device. ┬áThe various sections of the iPhone also have one or more low power modes of operation, essentially putting those sections to sleep if they’re not being used. For example, if you’re not presently making a phone call, the baseband chip that communicates with the cellular network can be placed in a low power mode until either a call comes in or the user initiates one. If a call starts up, iOS on the iPhone will wake up the baseband chip so the call can be handled, and when the call is done, the chip will be put back to sleep. Even the CPU itself can be placed in low power states. This happens anytime you press the lock button on your iPhone, iPad or iPod Touch, and as soon as you press the button to wake it up, the CPU wakes up, too. In addition, iOS takes advantage of low power states even when waiting for things like user input. Since you can only tap a couple of letters per second, the CPU can basically sleep in a lower power state in between each of your taps on the keyboard, and even these little “naps” can greatly extend battery life on the iPhone.

This power management is all great and wonderful and saves a significant amount of battery power which means you can go a much longer time between charges than you could otherwise. Unfortunately, things can and do go wrong. When that happens, almost always due to a software bug, the device fails to enter low power states and this basically eats your battery power alive. If the CPU on your iPhone runs continuously at full power for as little as an hour or so, the battery will be completely drained. That shows how important power management on Apple portable devices is for maintaining good battery life. You may also notice your iPhone or iPad getting warmer than it normally does. This is another sign that something has gone wrong and preventing the device from entering low power modes.

When rapid power drain is observed, it almost means that one or more threads or processes on the device have gotten stuck in an infinite loop which prevents the device from sleeping. The bug could be in an application or iOS, but either way, the stuck thread will want to run continuously which keeps the device from using any of the low power states normally available when the device idles (since it never goes idle). Again as mentioned above, this problem is not at all unique to the iPhone or iPad. All smart phones, including Android and Windows Mobile based phones, are susceptible to these sorts of bugs. And it’s not always Apple’s fault either. The problem could lie in one of the applications you downloaded.

The good news is that the workaround or fix for the rapid battery issue on iPhone and iPad is easy: just power cycle the device. Turning it off causes all threads and all programs to terminate, so whatever it was that was stuck in an infinite is terminated and everything is reset when you turn the device back on. There is always a slight chance that the bug will repeat, but that rarely happens in actual experience and the device’s power management will be able to properly mange the battery power from that point on (though of course you’ll probably need to charge the device soon to get the battery back to where it was before the rapid power drain issue started).

Category: Apple iPhone