Halftone Test Print (Pg>Type=5) - Canon CLC 1120 Service Manual

6. Halftone Test Print (PG>TYPE=5)
Use a halftone test print to check transfer faults, black lines, white lines, or uneven density at
regular intervals.
a. Transfer Fault
If a transfer fault is noted, suspect a fault on the transfer drum sheet, transfer blade, and static
eliminator.
b. Black Lines
If black lines are noted, suspect scratches on the photosensitive drum and dirt on the primary
charging wire/grid plate.
c. White Lines
If white lines are noted at the same position for all colors, suspect a fault on the transfer drum
sheet and dirt on the primary charging wire.
If they occur at different positions or if they are limited to a single color, suspect a fault in the
developing assembly.
d. Uneven Density at Regular Intervals
· Original scanner (at intervals of about 0.5 mm; not applicable to PGTYPE=5 test print)
· Developing cylinder (at intervals of about 42 mm)
· Bending mirror holder (at intervals of about 0.9 mm)
· Drive gear
Note:
1. You can generate a printout for each color using COPIER>TEST>PG of service mode and
selecting the following: COLOR-Y, COLOR-M, COLOR-C, COLOR-K.
2. If you want to change the density of the test print, use TEST>PG>DENS-Y, M, C, K.
COPYRIGHT © 1999 CANON INC. CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 13 TROUBLESHOOTING
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