If an iPhone reboots or restarts automatically and without warning, it could be because of a few different things: Power hungry programs or features, junk files, or even a worn-out battery. And because of the variety of issues, there is an abundance of solutions to solve them.
Detailed below are a few methods to troubleshoot and possibly solve these issues.
Rebooting an iPhone is not a bad thing in itself. A restart can help prevent a faulty app from crashing or give the phone a refresh that allows it to clear some memory. Like all computers, a phone needs to turn off once in a while to process data and update. Restarting is like giving an iPhone a quick nap.
But if an iPhone begins to do this on its own, not just once or twice, but many times, then it may be time to take it to the experts and get it replaced.
Or, possibly not. There are a few tips and tricks to try before you have to break the bank and get a brand-new device.
If the Phone is New:
If you have a brand-new phone with a restarting problem, and it is eligible for replacement then, by all means, go to the Apple Store or Official Service Center and get that faulty phone replaced.
Otherwise…
The issue can be caused by several different things, so there are several different solutions to try. IOS 11.3 and up have a few built-in tools like the “Battery Health” feature in settings that can help you run maintenance on your phone. It’s designed to optimize performance and prevent the phone from shutting down unexpectedly. If you have an iPhone 6 and up, check there as your first troubleshooting step.
Solution 1: Hard Reboot the device.
Force Restarting a device is one of the first and foremost solutions to this kind of problem. Just like a computer: Turn it off, then on again.
For an iPhone 6 or earlier: Simply press and hold the home button and the side (lock) button together for about 10 seconds or until the apple logo appears to reset your phone.
On the iPhone 7 and 7 plus: Hold the volume down button and the side (lock) button down until the apple logo appears on your screen to restart your phone.
On the iPhone X or iPhone 8 and 8 plus: press and release the volume up button, then press and release the volume down button, then hold the side (lock) button until the apple logo appears to reset your phone.
Side note: If you charge an iPhone in a low or high-temperature condition, the behavior of your device might change. A phone can overheat and turn off if the temperature is too high, or if charging in the sun on a hot day, and the battery can die very quickly if the temperature is too cold. Restoring the iPhone to a temperature between 0*C or 32*F and 35*C or 95*F will normally return iPhone behavior to its usual state.
Solution 2:
Turn off Power Hungry Features when they’re not being used.
Location tracking, screen brightness or particularly feature-heavy apps can all cause your phone to heat up and the battery to wear down far quicker than normal. Turning off location services when you’re not using them and making sure those apps aren’t running in the background can make your battery life last significantly longer.
You can see which apps take up the most power by going into Settings, then Battery. On that page is a list of your most used apps, arranged by battery usage for both the past 24 hours and the last 7 days, regardless of whether your phone has been plugged in or not.
Note: to close out of apps you’re no longer using, simply double press the home button to bring up the background apps page, in which the apps look like cards and swipe up to close an app that’s running.
You can scroll through them to decide which apps to close, or simply remove them all. Pressing and holding on a window will also cause a red x to appear in the corner and tapping that will also close the app. Swiping is the preferred method for iPhone experts since holding on an app for too short a time could just open the app up again.
On an iPhone X, to bring up the background apps screen, swipe up from the gesture bar and hold until the app windows appear.
Solution 3: Resetting the Device to Factory Settings
If you’ve tried the above solutions, it may be best to attempt a restore to factory settings. You can do this by opening the Settings app, selecting General then Reset and Reset all Settings. This does not delete your data but removes login details, Wi-Fi passwords, and other saved preferences.
Solution 4: Update Apps
If running a certain app causes a restart, it could be that the app is out of date and no longer compatible. Out of date apps can waste a lot of battery life, run slowly, or become completely unresponsive. All you have to do is open the app store, and select updates in the lower right corner, then the Update All button, which will find the apps that need updating and install the proper versions.
Solution 5: Removing Unused Apps
Like with any computer programs or games, there are some that just don’t hold your attention like they used to, or they aren’t necessary anymore. Simply deleting them can help both restore some of that precious commodity storage memory, as well as letting the iPhone run more smoothly.
An iPhone is a small computer, and just like deleting unnecessary programs on a computer helps it run smoother, so it is the same with deleting apps on an iPhone.
With iOS 11 came the feature to “offload” unused apps, which deletes them automatically after a set time, but without removing their icons or deleting their data, so apps that aren’t used don’t take up space, but when they’re reinstalled, it would be as if they were never gone. It also makes it easy to spot apps you don’t use much because offloaded apps have a little cloud icon beside their name.
Solution 6: Delete Faulty Apps
Some apps are just not good for the health of a phone. They could be old and no longer supported by the iTunes store, or simply glitchy or malignant on purpose. If a brand-new app was installed and then your phone began to restart automatically, then perhaps the app is at fault and simply removing it can solve the issue.
To get a clean delete: Delete the app, then restart the phone using solution 1, then sync with iTunes for the most thorough results.
Solution 7: Software Update/Restore from An Old Backup
If nothing else has worked so far, try updating your device to the latest software. This can be done from the settings menu, under general, select update. If you can’t, you can always update by plugging the phone into iTunes and either updating it or restoring it as a new phone. As always, remember to back up your data before restoring it or even updating it.
If you have just updated your phone and the problem has begun, then try restoring it to an older backup of the phone via iTunes, which will reset your iOS to an older version, one of the few options that will allow you to go back to an old version of iOS.
Solution 8: If None of That Works, Check If the Battery Needs Replacing
Random Rebooting can be the cause of a faulty battery. If you have iOS 11.3 or later, you can check the health of your battery under Settings, then Battery then Battery Health.
The Battery settings page also gives you information on what apps may be using the most power on your phone both in the last 24 hours and for the past 7 days. It also allows you to manually enter “Low Power Mode” which can help preserve battery if its health is low.
Keep in mind Low Power Mode does automatically turn off if the charge is high enough, but you can easily turn it back on from here.
If the battery does need replacing, or if you are unsure, the best advice is to take it to the experts at the Genius Bar. You can schedule an appointment online, or by calling the number for your local Apple store (Though it’s suggested you do either of those things from a device that does not reboot on its own).
Apple can replace the out of date battery for as low as 30 dollars, though it may take up to a few days for the device to be repaired. You can also visit iFixit for a battery replacement kit for 20$ if you are up to making the replacement yourself. It can be done, but it not a task for the faint of heart.
If none of these tricks have worked, it could just be time to get that old phone replaced. Take it to the geniuses at Apple, and they’ll help get you back to a working iPhone.