Image-Quality Problems; Repeating Defects - Xerox Phaser 6120 Service Manual

Image-Quality Problems

Image-quality defects can be attributed to printer components, consumable, media, internal
software, external software applications, and environmental conditions. To successfully
troubleshoot image-quality problems, as many variables as possible must be eliminated.
The following guidelines should be used before troubleshooting an image-quality problem:
Use an unopened ream of approved media for evaluating image-quality problems
Note:
See the approved media list,
been tested and approved for use with the Change to local value.
When analyzing a image-quality defect, first determine if the defect is repeating or
random. Repeating defects can often be associated with a particular component.
Inspect the surfaces of all rollers in the paper path for obvious defects.

Repeating Defects

Match the distance of the repeating spot or defect in your print and compare it to the
corresponding table below in order to identify the part responsible for the defect.
For example, your prints have a visible spot on the page. This spot repeats (down the page)
every 94.4mm. The chart identifies the Imaging Unit as the most likely cause of the defect.
Consumable, Routine
Maintenance or Service Item
Toner Cartridge
Transfer Belt
Imaging Unit
Transfer Roller
Fuser
Phaser® 6120 Color Laser Printer Service Manual
Media Specifications
Component
Developer Roller
Toner Supply Roller
Belt
PC Drum
Roller
Heat Roller
Backup Roller
Cleaning Roller
4-23

Image-Quality Problems

on page 1-5, for media that has
Distance on Page Between
Defect
34 mm
25 mm
379 mm
94.4 mm
50.4 mm
108 mm
115 mm
52 mm