Xerox PHASER 7500, Service Manual

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5-22 Phaser 7500 Printer Service Manual
Print-Quality Troubleshooting
Print-Quality Defect Definitions
The following table lists the print-quality defect corrective procedure, their
definition, and the page where each procedure is provided.
Defect Definition Page
IQ-1 1mm Stripes At 50% and 30% densities, the lines in the
process direction of a single color have
reversed black and white. 5-25
IQ-2 Image Shift in
Process Direction The image is shifted in the process direction. 5-26
IQ-3 White Stripes White stripes appear in the process direction
for all densities of a single color. 5-27
IQ-4 SLED Transfer
Cycle Stripes There are faded or completely non-printed
lines along the page in the direction of the
paper travel from the leading edge to the
trailing edge. 5-28
IQ-5 In/ Out Density
Difference The densities between the IN and OUT (front
and rear) sides are different. 5-29
IQ-6 Video Data/
Crosstalk An image with different color overlaps
another. 5-31
IQ-7 Image Shift in
Process The image lands on the blank area and gets
dragged in the FS direction. 5-32
IQ-8 Edge-less Image
(No Margins) An image is printed on the edges. 5-34
IQ-9 Contamination
Stripes There are blank areas. Their size is
proportional to the size of contaminants. 5-35
IQ-10 Chip/ Half Chip
Blanks Blank areas in sizes of 2.7mm or 5.4mm in a
single color. 5-36
IQ-11 SLED Transfer
Failure Stripes and blank areas (stripes) in an
individual color appear repeatedly in sizes of
2.7 mm. They appear by half chip units. 5-37
IQ-12 Tapes Not
Peeled The highlight portions are too obvious. The
whole paper seems to be filled with stripes. 5-39
IQ-13 Charging Roll
Pitch White Stripes - 1 If the BCR is deformed at the BCR and
Photoreceptor NIP sections, the trace may
appear as thin white stripes in the FS
direction on the highlight portion at the
Charging Roll Pitch. 5-40
IQ-14 Charging Roll
Pitch White Stripes - 2 If the substances contained in the CLN-Roll
get stuck to the BCR at the BCR and CLN-Roll
NIP sections, the resistance on the BCR gets
reduced and may cause the appearance of
white stripes in the FS direction. 5-41