Canon imageRUNNER ADVANCE 9070 PRO series Service Manual Digest page 775

■ Grid (TYPE=6)
This test print can mainly check color displacement, right angle accuracy and linearity.
(1) Color displacement
If there is color displacement, it may be caused by fault of each laser scanning system,
transfer (intermediate transfer/secondary transfer) unit or photosensitive drum drive unit.
(2) Right angle accuracy and linearity
If there is fault of right angle accuracy or linearity, it may be caused by fault of laser
scanning system, or defective shape of registration (upper/lower) roller or the secondary
transfer outer roller.
■ MCYBk Horizontal Line (TYPE=10)
This test print can mainly check the dark area density of each color, balance among each
color and white line by developing.
F-5-4
(1) Solid density of each color and balance among each color.
• Density is not extremely light.
• In the case of light density with a certain color, it may be caused by the developer of the
color in question, or fault of primary transfer roller, laser scanning system or high voltage
system.
(2) White/black line
If there is white/black line with a certain color, it may be caused by fault of the drum unit of
the color in question, or soiled laser light path.
(3) Density unevenness at the rear/front
If there is density unevenness with a certain color, it may be caused by fault of drum unit,
laser scanning system or transfer (intermediate transfer/secondary transfer) unit.
If there is density unevenness with all colors, it may be caused by deterioration of
intermediate transfer unit.
F-5-5
5
5-547