iPhone light sensor not working. Auto-brightness and true tone are grayed out
First try the simplest fixes: clean the light sensor at the top of your phone, restart your iPhone, and check that auto-brightness is actually turned on in settings. If those don't work, the sensor hardware can be damaged.
Your iPhone has a small light sensor at the top that measures room brightness and controls auto-brightness and true tone. When it fails, these features become unavailable. The sensor can fail because it's dirty, blocked, or actually broken from water or impact damage. We'll check the easy fixes first before assuming the hardware is damaged.
Fix-IT-Bot will walk you through each step — just tap, no typing needed.
Skip — I just want a technicianCommon mistakes to avoid
- Assuming the sensor is broken when a screen protector is just blocking it
- Not realizing that auto-brightness being OFF in settings is different from the sensor being broken
- Scrubbing the sensor aggressively or using harsh chemicals. This damages the lens
Signs you need professional help
- Auto-Brightness toggle is grayed out even after cleaning and restarting
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