Avision AV220D2+ (FF-0901H) - Manual (Page 95)

ADF Pad
Feeding
Roller
7.2 Cleaning the Calibration Area
1. Press the Paper Jam Clearing button. Open the front door
to the left.
2. Wet a cotton swab with some isopropyl alcohol. (95%)
3. Wipe the glass and the white area as illustrated in below by
moving the swab from side to side to rid the dust or dirt.
Glass
7-2