Canon imageRUNNER ADVANCE 9070 PRO series Service Manual Digest page 774

Test Print
How to check test print
■ 16-Gradation (TYPE=4)
This test print can mainly check gradation performance, image fogging, white line, and
density unevenness at the rear/front.
5
(1) Gradation
If there is no 16-step density gradation, it may be caused by fault of drum unit or laser
scanning system.
(2) Foggy image
If there is foggy image only at the white area as shown in the figure below, it may be
caused by fault of drum unit or laser scanning system.
(3) Vertical white/black line
If there is white line in the image, it may be caused by fault of developing system.
(4) Density unevenness at the rear/front
If there is density unevenness at the rear/front, it may be caused by fault of drum unit, laser
scanning system or transfer unit.
5-546
■ Full Area Half Tone (TYPE=5)
This test print can mainly check transfer failure, black line, white line, and pitch unevenness.
16-Gradation
NOTE:
• Output by every developing color is available by specifying the developing color
COLOR-Y/M/C/K in the following service mode: COPIER>TEST>PG
• In the case of changing density of the test print, execute followings in service mode for
F-5-2
density setting: TEST>PG>DENS-Y/M/C/K
(1) Transfer failure
If there is transfer failure, it may be caused by fault of transfer (intermediate transfer/
secondary transfer) unit.
(2) Horizontal unevenness
If there is horizontal unevenness, it may be caused by fault of photosensitive drum drive
unit, drum ITB motor, or drum unit.
(3) Vertical unevenness
If there is vertical unevenness, it may be caused by soiled LDE lens, fault of drum unit, or
deterioration of intermediate transfer belt.
COLOR-M=1, COLOR-Y/C/K=0
F-5-3