Periodic Defective Image (Repeating Defects) - Xerox Phaser 3150 Service Manual

6.7 Periodic Defective Image (Repeating Defects)

If a mark or other printing defect occurs at regular intervals down the printed page it may be caused by a damaged or
contaminated roller. Measure the repeating defect and refer to the table below to identify the problem component.
No Roller
1 OPC Drum
2 Charge Roller
3 Supply Roller
4 Developing Roller
5 Transfer Roller
6 Heat Roller
7 Pressure Roller
PTL
Defective image
75.5 mm white spot on black image or black spot
37.7 mm black spot
44.9 mm light or dark horizontal image band
35.3 mm horizontal image band
47.1 mm image ghost
78 mm black spot and image ghost
75.5 mm black spot on the backside
Alignment and Adjustments
Typical defect
Service Manual 6-11