Canon LBP-1000 Service Manual page 130

CHAPTER 4
Action: Replace the cartridge.
3. Defective engine controller PCB.
Action: Replace the engine controller PCB.
II-5. Dots in vertical line
<Possible causes>
1. Dirty static charge eliminator
Action: Clean the eliminator with brush.
2. Poor contact in the static charge eliminator contact on the engine controller PCB and in the
static charge eliminator contact.
Action: Clean the contacts if dirty. If the problem remains after cleaning, or parts are
deformed or damaged, replace them.
3. Deformation or deterioration of the transfer charging roller
Action: Replace the transfer charging roller.
4. Poor contact in the transfer charging roller contact on the engine controller PCB and in the
transfer charging roller shaft contact.
Action: Clean the contacts if dirty. If the problem remains after cleaning, or parts are
deformed or damaged, replace them.
5. Defective engine controller PCB
Action: Replace the engine controller PCB.
II-6. Dirt on back of paper
<Possible causes>
1. Dirty paper
Action: Replace the paper with new one. Advise the customer on how to store paper.
2. Periodic dirt (Registration roller, transfer charging roller, pressure roller)
Action: Identify and clean the dirty roller according to Table 4-2-1 on page 4-11. If dirt can-
not be removed, replace the dirty roller.
3. Dirty feed belt, feed guide or fixing unit entrance guide
Action: Clean the dirty areas.
II-7. Vertical lines
<Possible causes>
1. Circumferential scars on the photosensitive drum
Action: Replace the cartridge.
2. Dirty fixing unit entrance guide
Action: Clean the guide.
3. Scar(s) on fixing film unit
Action: Remove the cause of the scar(s) and replace the unit.
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