CHAPTER 4

II-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 connec- tion 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 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. Action: Replace the high-voltage power supply PCB.

5.The DC controller PCB is defective. Action: Replace the DC controller PCB.

II-3. Completely blank

<Possible causes>

1.The projection for opening and closing the laser shutter of the EP-72 cartridge is damaged. Action: Replace the cartridge.

2.The laser shutter arm or laser shutter is malfunctioning or damaged.

Action: If the laser shutter arm or laser shutter does not move smoothly, or parts are dam- aged, replace them.

3.The developing bias contact of the high-voltage power supply is not making a good connec- tion 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. Action: Replace the high-voltage power supply PCB.

5.The DC controller PCB is defective. Action: Replace the DC controller PCB.

II-4. All black

<Possible causes>

1.The primary 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.

2.Defective primary charging roller

4 - 9

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Image 169
Canon 3260 manual II-2. Dark, II-3. Completely blank, II-4. All black