iPhone auto-brightness not working. Screen brightness won't adjust
Turn auto-brightness off and back on. If that doesn't work, try turning off True Tone, then restart your phone. If the light sensor is dirty, cleaning it fixes it.
Auto-brightness uses a light sensor to detect room brightness and adjust your screen automatically. When it stops working, it's because the setting got turned off by accident, True Tone is interfering, or the setting cache got corrupted. Rarely, the light sensor itself isn't working. We'll check the easy fixes first.
- ✓Check Settings → Display & Brightness. Is the auto-brightness toggle actually ON?
- ✓If True Tone is turned on, try turning it off temporarily to see if it interferes
- ✓Move your phone from a bright room to a dark room and watch for 5 seconds to test
Fix-IT-Bot will walk you through each step, just tap, no typing needed.
Skip, I just want a technicianCommon mistakes to avoid
- Expecting brightness to change instantly. It actually adjusts gradually over a few seconds
- Turning off True Tone permanently thinking you've fixed it. You can turn it back on once auto-brightness is working
- Giving up after one test instead of moving between bright and dark areas a few times
Signs you need professional help
- Auto-brightness doesn't work after trying all these steps. The light sensor hardware can be damaged and needs professional inspection. Get in touch and we'll arrange a replacement if needed.
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