Canon 1730, Service Manual

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Troubleshooting > Test Print > How to View the Test Print > Halftone (TYPE=02)
Troubleshooting > Test Print > How to View the Test Print > Halftone (TYPE=02)
How to View the Test Print
■ Grid (TYPE=01)
Check item Check method Assumed cause
Right angle
accuracy/
Straight line
accuracy
Check whether lines in the horizontal/
vertical scanning directions are
paralleled to the paper and these lines
are at right angles to one another.
Feed system failure or Laser Scanner Unit
failure is considered.
Side
registration
Check the left margin.
Floor at the installation site is extremely
distorted, or the feed system failure is
considered.
F-6-1
T-6-4
■
Halftone (TYPE=02)
Check item Check method Assumed cause
Transfer failure
Check the evenness of halftone
density. Check whether uneven image
or foggy image appears.
Transfer system failure or transfer roller
failure is considered.
Black line
Check whether black lines appear on
the image.
Laser light path failure, grid failure,
developing system failure, cleaning (drum)
failure or transfer roller failure is considered.
White line
Check whether white lines appear on
the image.
Developing system failure is considered.
Uneven pitch
Check whether lines appear on the
image in the horizontal scanning
direction.
Drum failure, developing system failure,
laser exposure system failure or drive-
related failure is considered.
Uneven
density
(rear/front)
Check the density difference between
the front and rear sides.
Drum failure or developing system failure is
considered.
F-6-2
T-6-5