Brother International HL 1240 Service Manual - Page 145

CHAPTER 6 TROUBLESHOOTING NOTE: Clean the drum unit as follows: (1) Remove the toner cartridge from the drum unit Place the printing samples in front of the drum unit, and find the exact position of the image defect. Drum unit Position of smudge on the drum 94mm interval Printing sample Fig. 6-7 (2) Turn the drum gear by hand while looking at the surface of the photosensitive drum. Photosensitive drum Fig. 6-8 (3) Wipe the surface of the photosensitive drum with a cotton swab until the dust or paper powder on the surface comes off. Photosensitive drum Fig. 6-9 ! CAUTION: Do not wipe the surface of the photosensitive drum with something sharp. (ball-point pen etc.) Use the cleaning liquid which is a 50-50 mixture of ethyl alcohol and pure water. 6-35