Xerox Phaser 8560MFP Service Documentation page 109

Figure 5 Test Print 5 Big Bands OHP
Grey Fill, Dot Size Uniformity
This print is made up of a 66% black fill. It reveals variations in the ink-drop-spread caused by
thermal variations, transfix roller pressure variations, or drum oiling variations.
Look for: There is a large area of differences in the density across the width of the page (a
slight variation is normal). Look for a lighter vertical band, about 1/3 the width of the page, run-
ning the length of the page. Look for small, light spots, or irregular white lines, vertically aligned
with each other, in the print every 125 mm (5.0 in.).
Look for ink on the top and bottom margin of the page, or ink on the back of the page. This pat-
tern is sensitive to the density variations in the paper it is printed on. Use a high-quality grade
of system paper; otherwise, the print appears mottled.
Causes: Use the diagnostics to check the printhead and drum for correct thermal regulation.
Ensure the drum fan is running properly. A vertical band, 1/3 of a page wide, running the length
of the page, is caused by a stuck heating plate in the Preheater. Run the control panel cleaning
procedure Clean Print Smears, which raises the temperature of the Preheater and may free the
stuck heating plate. Additionally, you may manually force a thick sheet of paper (65 to 80 lbs.)
through the paper Preheater to jar the plate free. Light spots that repeat every 11.63 cm (4.58
in.) down the length of the page are caused by a defective transfix roller. The roller has a soft
spot that is not pushing the ink into the paper as well as the rest of the roller. If you observe
variations in the glossiness of the print, replace the maintenance kit.
Initial Issue
Phaser 8510/8560MFP Multifunction Product
If there is ink on the top and bottom margin of the page or ink on the back of the page, it may
be caused by the roller remaining down during the print. You may hear an unusual noise if the
Transfix Roller stays down and rubs against the drum. Inspect the Drive Train and ensure that it
self-homes between prints. The drive train is in its home position when the two 1.5 mm holes
found on the clear plastic cover align axially with corresponding holes in the gear. Another way
to verify that the drive train is in its home position is to verify that the two small leaf springs from
the clear plastic cover are seated correctly in their corresponding gear slots. Inspect the perim-
eter of the cam lobes for surface defects and check to see that the angular orientations of the
cams match. Inspect the transfix load arm return springs. Verify that the maintenance kit
returns home between prints. Inspect the cam shaft surfaces for damage. If all of these items
are working correctly, replace the process drive module.
Figure 6 Grey Fill, Dot Size Uniformity Test Print
Five Duplex GSF
This print is used by Manufacturing and Engineering only.
YMCKRGB Solid Fills
This test prints a single-sided, solid-fill print in all seven colors to show uniformity of fill. If colors
are uneven or wrong, see IQ18.
Look for:
• Even, uniform fill throughout each print.
• Wrinkles or deformity of the paper.
• Proper ink transfer.
• White striping or banding.
10/2006
3-27
Image Quality