Service manual

Image Defect Troubleshooting (Defect of the Print)
SM 6-65 M085/M086
Trouble –
shooting
21 Fogging
User Check
1. Replace the toner cartridge with a new one.
2. Replace the drum unit with a new one.
3. Do not use acid paper.
4. Check if there is dust or paper powder in the machine.
Possible cause and Remedy
1. Toner sensor failure (Machine body)
 Is the toner sensor performed normally by following the procedure in p.5-19
"Operational Check of Sensors (Function code 32)"?
No: Replace the toner sensor PCB unit ASSY and the toner LED PCB ASSY.
2. HVPS PCB failure
 Is the problem solved after replacing the HVPS PCB ASSY?
Yes: Replace the HVPS PCB ASSY.
3. Main PCB failure
 Is the problem solved after replacing the main PCB ASSY?
Yes: Replace the main PCB ASSY.
 This problem often occurs when the drum unit or toner cartridge is nearly at the end of
life.