What to Do If Your iPhone 15 or 18 Pro Shows a Temperature Warning or Shuts Off Unexpectedly

If your iPhone 15 or 18 Pro is stuck on a temperature warning or keeps shutting off by itself, try cooling it down, restarting it, and updating iOS. Persistent issues may require resetting settings or contacting Apple Support for hardware diagnostics.

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Your iPhone 15 or 18 Pro: what you need to know

Why Does My iPhone 15 or 18 Pro Show a Temperature Warning or Shut Off Unexpectedly?

Modern iPhones, including the iPhone 15 and 18 Pro models, are equipped with advanced temperature sensors designed to monitor the device's internal heat levels. These sensors play a crucial role in protecting the phone’s internal components from damage caused by overheating. When the iPhone detects that it has reached a temperature beyond its safe operating range, it will display a temperature warning on the screen. In some cases, the device may even shut down automatically to prevent potential hardware damage.

While this feature is essential for device longevity and user safety, it can sometimes cause frustration if your iPhone remains stuck on the temperature warning screen or powers off unexpectedly without apparent cause. This behavior might indicate underlying issues such as software glitches, sensor malfunctions, or hardware defects. Understanding why this happens and how to address it can help you restore your iPhone to normal operation.

How to Fix an iPhone Stuck on a Temperature Warning or That Keeps Turning Off

1. Move Your iPhone to a Cooler Environment

The first and most straightforward step is to ensure your iPhone is not exposed to excessive heat. Direct sunlight, hot cars, or warm indoor environments can cause the device to overheat quickly. Remove any protective case that might trap heat and place your iPhone in a shaded, well-ventilated area. Allow it to cool down naturally before attempting to use it again. Avoid placing it in extreme cold environments like a freezer, as rapid temperature changes can also harm the device.

For example, if you were using your iPhone outdoors on a hot summer day, moving indoors to an air-conditioned room can help the device cool off. Similarly, if you notice the temperature warning after charging your phone, unplug it and let it rest in a cooler spot.

2. Force Restart Your iPhone

If your iPhone remains stuck on the temperature warning screen or shuts off unexpectedly even after cooling down, a force restart can help clear temporary software glitches that might be causing the problem. For iPhone 15 and 18 Pro models, the process is as follows:

Quickly press and release the volume up button.
Quickly press and release the volume down button.
Press and hold the side button until the Apple logo appears on the screen.

This method forces the device to reboot without affecting your data. It's a useful troubleshooting step when the device becomes unresponsive or stuck in a warning state.

3. Update iOS to the Latest Version

Software updates often include important bug fixes and improvements that can resolve issues related to temperature warnings and unexpected shutdowns. Apple regularly releases updates to optimize system performance and address known problems.

To check for updates, connect your iPhone to a Wi-Fi network and navigate to Settings > General > Software Update. If an update is available, download and install it. Keeping your iPhone’s software up to date ensures you benefit from the latest fixes and enhancements.

4. Reset All Settings

If the temperature warning or shutdown issue persists after updating iOS, resetting all settings can help resolve conflicts caused by misconfigured preferences or system settings. This action does not delete your personal data such as photos, messages, or apps, but it will reset system settings like Wi-Fi passwords, wallpaper, and privacy preferences.

To reset all settings, go to Settings > General > Transfer or Reset iPhone > Reset > Reset All Settings. After the reset, you will need to re-enter Wi-Fi passwords and adjust settings as needed, but this step can often clear underlying software conflicts affecting device temperature management.

5. Check for Battery or Hardware Issues

Persistent temperature warnings or unexpected shutdowns can sometimes indicate hardware problems, particularly with the battery. Batteries that are degraded, swollen, or damaged can generate excess heat or fail to regulate power properly, triggering temperature alerts.

You can check your battery’s health by going to Settings > Battery > Battery Health & Charging. Here, you can view the maximum capacity of your battery and whether it is operating at peak performance. If the battery health is significantly degraded or if you notice physical signs like swelling, it is important to seek professional assistance.

In such cases, contact Apple Support or visit an authorized service provider for a thorough diagnostic. They can determine if a battery replacement or other hardware repair is necessary to resolve the overheating issue.

If the Problem Continues

Should your iPhone 15 or 18 Pro remain stuck on the temperature warning or continue to power off unexpectedly despite following all the troubleshooting steps, it may be suffering from a faulty temperature sensor or other internal hardware defects. Using the device in extreme temperatures can exacerbate these issues, so it’s best to avoid such conditions.

Regularly backing up your data is crucial in case the device needs to be repaired or replaced. You can back up your iPhone using iCloud or connect it to a computer with iTunes or Finder for a local backup.

Ultimately, reaching out to Apple Support or visiting an authorized service center is recommended for professional diagnosis and repair options. Attempting to fix hardware issues yourself can risk further damage and void warranties.