Xerox WorkCentre 7665
Troubleshooting. Image Quality. IQ04 Repeating Bands, Streaks, Spots, and Smears RAP
Bands, Streaks, Spots, and Smears appear on the image at a regular pitch.
Procedure
Measure the distance between the repeating defects.
Locate the distance on Table 1 and perform the indicated repair action.
Table 1 Repeating Defects Spacing Chart
| Repetition Spacing (mm) | Components |
|---|---|
| 0.3 | ROS (Stitching) |
| 1 | Developer Assembly / Developer Drives |
| 2 | Developer Assembly / Developer Drives |
| 6 | Developer Assembly / Xero/IBT / Developer Drives |
| 44 | BCR (Y, M, C) |
| 36 | Developer Roller (K, Y, M, C) |
| 36 (Horizontal streaks) | Developer Drive |
| 58 | 1st BTR |
| 62.8 | 2nd BUR |
| 88 | 2nd BTR |
| 98 | Fuser Belt |
| 110 | Heat Roll |
| 126 | Y/M/C Drum |
| 188 | Black Drum |
Corrective procedure for 0.3mm white/black streaks
Stitching is an Image Defect that appears as Streaking. Stitching is caused by a change in the Image Density from the first set of 32 scanning beams and the next set of scanning beams. Stitching normally results in black streaks of 0.3mm Pitch. However, over correction will produce white streaks. To correct black streaks, change the NVM Value in the plus (+) direction. This will strengthen the stitching action. To correct white streaks, change the NVM Value in the minus (-) direction.
NOTE:
It may be difficult to visually detect small changes. Make a large change in one direction and work backwards in small increments. When no change can be detected after a value has been changed, replace the relevant ROS (PL 5.1).