iPhone 12PM screen dims in sunlight

Hello groovdafied, 

Apple Support Communities is a great place for help with the display brightness on your iPhone 12 Pro Max. 

It sounds as though you’ve walked through great steps with checking the display settings, and verify no external factors such as screen protector or phone case are covering the sensor. You mentioned verifying that Auto-Brightness was disabled. To confirm you verified this in Settings > Accessibility > Display & Text Size? If so, and with the other steps you’ve taken you’ll want to verify you’re running the latest iOS. You can find the steps for updating in the following article. 

Update your iPhone, iPad, or iPod touch

If you’re running the latest iOS you’ll also want to make sure settings such as Night shift aren’t playing a factor in the issue you’re facing. You can find more information about this feature along with other display settings in the article below. 

Adjust the brightness and color temperature on your iPhone, iPad, or iPod touch

If you continue to have issues with these settings disabled you’ll want to reach out to Apple. You can find their contact details online via the Get Support website. 

Take care!

Hello groovdafied, 

We’re glad you had the opportunity to restart your device and verified those settings. With those settings disabled you would want to reach out to Apple next. The Get Support website previously provided is a great website to locate their contact details. 

Have a great day!