How to Fix an iPhone 17 That Keeps Rebooting Unexpectedly in iOS 15.2.1

How to Fix an iPhone 17 That Keeps Rebooting Unexpectedly in iOS 15.2.1

It can be frustrating when your iPhone 17 keeps restarting on its own. You might be texting, scrolling through social media, or using an app, and suddenly the screen goes black, the Apple logo appears, and your phone reboots. This issue can happen due to software bugs, faulty apps, or even low storage space.

If your iPhone 17 is stuck in this restart loop, don’t worry. Here’s how to stop the unexpected reboots and get your phone running smoothly again.

Why Your iPhone 17 Might Keep Rebooting

  • A recent iOS update didn’t install correctly.
  • An app is crashing repeatedly or running in the background.
  • Low internal storage causing system instability.
  • Corrupted system files or outdated settings.
  • Battery health or overheating issues.

Check for Pending iOS Updates.

Software updates often contain bug fixes that address random rebooting issues. Updating your iPhone ensures system stability and better performance.

  1. Open Settings, and then tap General.
  2. Tap Software Update, and then check if a new version is available.

If an update is found, download and install it, then restart your device manually afterward.

Free Up Storage Space.

When your iPhone runs low on storage, it can cause random crashes and reboots. Clearing out unnecessary files often improves performance.

  1. Open Settings, and then tap General.
  2. Tap iPhone Storage, and then delete unused apps or large media files you no longer need.

Keeping at least 2–3 GB of free space helps prevent background processes from freezing or restarting the device.

Check for Faulty Apps.

Some third-party apps can cause instability if they are outdated or poorly coded. Identifying and removing these apps can stop unexpected reboots.

  1. Go to Settings, and then tap Privacy & Security.
  2. Tap Analytics & Improvements, and then tap Analytics Data to check for frequently listed apps that might be crashing.

Uninstall any suspicious or recently downloaded app and see if your phone stabilizes.

Reset All Settings.

If software settings are corrupted, your iPhone might keep rebooting. Resetting all settings restores system preferences without deleting personal data.

  1. Open Settings, and then tap General.
  2. Tap Transfer or Reset iPhone, and then tap Reset All Settings.

Your device will restart afterward with all default configurations restored.

Check Battery Health.

A worn-out battery can trigger spontaneous restarts. Checking its condition will help you determine if it needs service.

  1. Open Settings, and then tap Battery.
  2. Tap Battery Health & Charging, and then check the Maximum Capacity value.

If the capacity is below 80%, it may be time to replace the battery through Apple Support.

Restore iPhone via Finder or iTunes.

If none of the steps work, restoring your iPhone using a computer can eliminate deeper software issues.

  1. Connect your iPhone 17 to a computer using a USB cable, and then open Finder or iTunes.
  2. Select your device, click Restore iPhone, and follow the onscreen instructions.

This reinstalls iOS 15.2.1 cleanly, fixing possible corrupted system files.

Once your iPhone 17 stops rebooting, make sure to keep it updated and avoid installing unverified apps. It’s also a good idea to monitor storage space and battery condition regularly to maintain smooth performance.


FAQs

Why does my iPhone restart randomly even when idle?

This often happens when background apps crash or the phone overheats. Check for app updates and clear storage to reduce the issue.

Will resetting all settings delete my photos and messages?

No. Resetting all settings only reverts system configurations like Wi-Fi passwords and display preferences. Your personal data remains intact.

Should I perform a factory reset if my iPhone keeps rebooting?

Only if all other methods fail. A factory reset erases all data and should be done as a last resort, preferably after backing up your files.

Leie Gabrielle is a college student with a deep passion for technology, gaming, and all things digital. When he’s not buried in coursework, he’s exploring the latest gadgets, leveling up in his favorite games, or breaking down tech trends for curious minds. With a sharp eye for innovation and a love for learning, Gabrielle brings fresh perspectives to the ever-evolving digital world.