Canon EOS 77D User Manual - Page 343

3 Manual Sensor CleaningN Dust that could not be removed by the automatic sensor cleaning can be removed manually with a commercially-available blower, etc. Before cleaning the sensor, detach the lens from the camera. The image sensor is extremely delicate. If the sensor needs to be cleaned directly, having it done by a Canon Service Center is recommended. 1 Select [Sensor cleaning].  Under the [54] tab, select [Sensor cleaning], then press . 2 Select [Clean manually].  Select [Clean manually], then press . 3 Select [OK].  Select [OK], then press .  In a moment, the reflex mirror will lock up and the shutter will open.  "CLn" will blink on the LCD panel. 4 Clean the sensor. 5 End the cleaning.  Set the power switch to . If you use a battery, make sure it is fully charged. Using the household power outlet accessories (sold separately, p.422) is recommended. 343