Xerox Phaser 7750DXF, Service Manual, Page: 182 / 505

5-22 Phaser 7750 Printer Service Manual
Background Contamination
There is toner contamination on all or
most of the page. The contamination
appears as a very light gray dusting.
The printer displays no error code.
1. Ensure that the loaded media
matches the front panel settings. In
some cases, switching the paper
type setting, for example from
Heavy Laser Paper
to
Thin
Cover/Index , may improve print
quality.
2. Run the Calibrate for Paper
routine. From the front panel’s
Printer Setup Menu, select
Calibration Setup , then select
Calibrate for Paper
.
Note
Printing on some specialty
papers, such as some glossy
finish papers may show some background contamination.
3. Inspect the imaging units for contamination. Replace the imaging units, if
necessary.
4. If the transfer roller or belt cleaner assembly is near the end of its life, replace
that part.
5.
If the background contamination is a primary color (and that primary color is
missing from the print), the high-voltage wire leading to that color’s developer
housing is grounded. Inspect the high-voltage wiring harnesses.
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