[Android Central Question]

Android LG 30

[Rukbat]

There are a lot of sensors, so I assume you mean the fingerprint sensor.

Wash your hands, dry them and let them warm up. Then stand with your hands at your sides for a minute or two, to let some blood get down to your fingers to plump them up. Then try. (That's usually the cause of the "clean the sensor" message - not a dirty sensor, a defective fingerprint.)

If it's really a dirty sensor, a Q-tip dipped into rubbing alcohol (7-% is fine, but 90% is also okay), rolled around the inside of the neck of the bottle to make it damp, not wet. A few swipes of the sensor will clean it. (About the only cause of "dirt" that causes the sensor to fail is skin oils, and alcohol cleans them.)

[ManiacJoe]

Otherwise, if you are talking about the camera sensor, you cannot clean that. It is buried inside the sealed phone case. The only thing you the user can clean is the protective covering over the lenses and flash.