Image Defect - Canon LBP 2460 - B/W Laser Printer Service Manual

CHAPTER 4
C. Image Defect Troubleshooting
I-1 Light
<Possible causes>
1. The image density is not adjusted correctly.
Action: Adjust the image density by operating the external device.
2. Lack of toner
Action: Replace the cartridge.
3. Open the upper cover and remove the EP-W cartridge while a print is being made. Open the
drum protective shield of the EP-W cartridge and check the toner image on the photosensitive
drum. If the toner image was not been transferred to the paper properly, go to step 4. If the
toner image on the drum is faint, go to step 7.
Do not open the drum protective shield for more than 10 seconds.
4. Print paper
Action: Replace the print paper. Advise the customer how to store print paper.
5. The transfer charging roller contact of the high-voltage power supply is not making good a
connection with the contact of the transfer charging roller shaft.
Action: If the contacts are dirty, clean them. If the problem continues after cleaning, or parts
are deformed or damaged, replace them.
6. The transfer charging roller is deformed or has deteriorated.
Action: Replace the roller.
7. The high-voltage power supply PCB is defective.
Action: Replace the high-voltage power supply PCB.
8. The DC controller PCB is defective.
Action: Replace the DC controller PCB.
I-2 Dark
<Possible causes>
1. The image density is not adjusted correctly.
Action: Adjust the image density by operating the external device.
2. The drum grounding contact of the high-voltage power supply is not making a good
connection with the cartridge contact.
Action: If the contacts are dirty, clean them. If the problem continues after cleaning, or parts
are deformed or damaged, replace them.
3. The primary changing roller-bias contact of the high-voltage power supply is not making a
good connection with the cartridge contact.
Action: If the contacts are dirty, clean them. If the problem continues after cleaning, or parts
are deformed or damaged, replace them.
4. The high-voltage power supply PCB is defective.
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