Service manual

Image Defect Troubleshooting (Defect of the Print)
SM 6-59 M085/M086
Trouble –
shooting
15 White spots
User Check
1. Toner may be empty. Replace the toner cartridge with a new one.
2. If the problem is not solved after printing a few pages, the drum unit may have glue from
label stuck on the exposure drum surface. Refer to the procedures below, and wipe it off
gently with a cotton swab.
3. The drum unit may be damaged. Replace the drum unit with a new one.
Possible cause and Remedy
1. Toner attached on the develop roller
 Are the white spots at 40.6 mm (develop roller circumference) intervals?
Yes: This problem will disappear by printing approximate 10 pages. If the same
problem occurs, replace the toner cartridge.
2. Scratch and Dirt on the exposure drum
 Are the white spots at 75.0 mm (exposure drum circumference) intervals?
Yes: Replace the drum unit.
3. Drum unit connection failure
 Are the electrodes on the drum unit and machine body dirty?
Yes: Clean both electrodes. (
p.6-21 "Electrodes location on the drum unit" and
p.6-21 "Electrodes location on the machine")
4. HVPS PCB failure
 Is the problem solved after replacing the HVPS PCB ASSY?
Yes: Replace the HVPS PCB ASSY.
5. Main PCB failure
 Is the problem solved after replacing the main PCB ASSY?
Yes: Replace the main PCB ASSY.
<Clean the drum unit as follows>
If you have print quality problems, clean the drum unit as follows: