CHAPTER 7 TROUBLESHOOTING
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Black and blurred vertical streaks
User Check (1) Clean the corona wire in the drum unit. (2) Check that the corona wire cleaner is at the home position. (3) Check that the toner cartridge is not empty. (4) The drum unit may be damaged. Install a new drum unit. (5) The toner cartridge may be damaged. Install a new toner cartridge.
<Scanning> Possible cause Dirt on the CIS window Dirt on the document pressure bar Scratch on the document pressure bar <Printing> Possible cause Corona failure Step 1 Check Is the vertical block streak about 10mm wide? (Check if the wire cleaner is at its home position.) Is the paper cassette or feed system on the drum unit dirty with toner? Is the drum surface scratched? Is the drum surface dirty with toner in streaks? Is the surface of the heat roller scratched? Result Yes Remedy Return the wire cleaner to its home position. Step 1 2 Check Is there any dirt on the CIS window? Is the document pressure bar dirty? Are there any scratches on the document pressure bar? Result Yes Yes Remedy Clean the CIS window. Clean the document pressure bar. Replace the document pressure bar.
3
Yes
Dirt in the paper feed system Scratch on the drum Cleaning failure Scratch on the heat roller
2
Yes
Clean the toner off.
3 4 5
Yes Yes Yes
Replace the drum unit. Replace the drum unit. Replace the fixing unit.
NOTE: � If you print the same pattern continuously, the drum will be worn and black vertical streaks will appear on the paper. � This problem may occur with noise due to the corona wire dirty. In that case, clean the corona wire with the wire cleaner.
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