User`s guide

147Troubleshooting
Lines across the page
• Clean the corona wire inside the drum unit.
• Clean the drum unit.
• The drum unit may be damaged.
Replace the drum unit with a new drum unit.
White lines, bands or ribbing
across the page
• Check the machine's environment. Conditions such as high humidity and high
temperatures may cause this print quality problem.
• Clean the drum unit.
• If the problem is not solved after printing a few pages, replace the drum unit with a new
drum unit.
White Spots on black text
and graphics at 3.7 in. (94
mm) intervals
Black spots at 3.7 in. (94 mm)
intervals
• Make 10-15 copies of a blank, white sheet of paper. If the problem is not solved after
printing the blank pages, the drum unit may have foreign material, such as glue from a
label, stuck on the drum. Clean the drum unit.
• The drum unit may be damaged.
Replace the drum unit with a new drum unit.