My iPhone 11 screen will dim on its own

Hello Jojotx, 

Thanks for reaching out to the Apple Support Communities! I understand from your message the screen on your iPhone has been dimming, without the auto-brightness setting being on. 

If you are using the auto-lock setting the screen will dim when the iPhone is not in just, just before it turns off. If the dimming is occurring while you're using the iPhone, Begin with restarting your iPhone following these steps: Restart your iPhone. 

Once restarted, if the issue reoccurs and you notice it's occurring in only one app, follow these steps with that app: If an app unexpectedly quits, stops responding, or won’t open. 

If after restarting the issue persists, go to the auto-brightness settings (Settings > General > Accessibility > Display & Text Size.). Toggle auto-brightness on, then back off, and see if there is any change.

If you notice this is only occurring at certain times of the day, check under Settings > Display & Brightness to check the Night Shift setting.

All the best!

Hi Jojotx,

Based on the additional information you've provided about what's occurred, you’ll want to be sure to have your iPhone evaluated by an authorized service provider. Depending on your location this may be an Apple Store, Apple Authorized Service Provider, or Apple Authorized Distributor. This site will help you to locate the service providers in your region: Apple - Find Locations.

Before taking your iPhone in for service, you’ll want to have a backup of your data. Having a backup of your data is like having an insurance policy, you don’t plan on using it, but it’s great to have if you need it. This article will provide you with a link to follow for how to backup your iPhone, as well as other steps you will want to take before your service evaluation: Get your iPhone, iPad, or iPod touch ready for service - Apple Support.

Cheers!