light sensor doesn't work

[Mobin1]

In diagnostics light sensor test the display doesn't fade why please help me

[_alexdon_]

When you test the sensor,if you cover it,you will get the message on.

[Mobin1]

the diagnostics light sensor test says(Hold your hand over the upper part of the device the image will fade when the sensor is covered) even I hold my hand over the upper part of the device the image doesn't fade

[_alexdon_]

There should also be a message ON and OFF. Does it change?