Oki ES3640MFP Service & Troubleshooting Manual page 43

Chapter 3
Troubleshooting Print Quality
3.1 Print-Quality Problems Overview
Print-quality defects can be attributed to printer components, consumables, media,
internal software, external software applications, and environmental conditions. To
successfully troubleshoot print-quality problems, eliminate as many variables as
possible. The first step is to generate prints using printable pages embedded in the
printer on paper from the Supported Media List. Use paper from a fresh, unopened
ream that is acclimated to room temperature and humidity. If the print-quality
defect is still present when printing on approved media, then investigate software
applications and environmental conditions.
The printers use separate Imaging Units to develop a latent image for each color
where the colors are combined on the Transfer Unit to form the final image. In
most cases, print-quality defects are the result of one particular component in the
print engine, See the Repeating Defects chart. When a single component of the
Imaging Unit is causing a print quality defect, replace the Imaging Unit.
When analyzing a print-quality defect, first determine if the defect occurs in all
colors or only one color and if it is repeating or random. Continuous defects in the
process direction, such as voids and lines, are the most difficult to diagnose.
Inspect the visible surfaces of all rollers for obvious defects. If no defects are
observed, replace the Imaging Units, Transfer Unit, and Fuser one at a time until
the defect is eliminated.