Canon MultiPASS C755, Service Manual, Page: 83 / 143

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MultiPASS C755 Chapter 3: Maintenance & Service
Missing dots
Unstable printing Splashed dots
Figure 3-12 Defective Pattern (Sample)
• Printing quality error
• The printer does not at all.
• Printing stops midway.
• Certain colors are not printed.
(1) Check that the orange cap or tape is not on the BJ cartridge.
(2) Carry out nozzle cleaning on the BJ cartridge five times with the cleaning operation, than visually
cheek the test print for non-discharge of ink from nozzle. (
Fig. 3-12
)
(3) Remove and reinstall the BJ cartridge.
(4) Replace the appropriate ink tank.
(5) Replace the BJ cartridge.
(6) Replace the purge unit.
• Blotches appear
• Blank ink appear
(1) Carry out nozzle cleaning on the BJ cartridge five times with the cleaning operation, than visually
cheek the test print for non-discharge of ink from nozzle. (
Fig. 3-12
)
(2) Remove and reinstall the BJ cartridge.
(3) Replace the appropriate ink tank.
(4) Replace the BJ cartridge.
(5) Check the connection of the carriage ribbon cable and the PCNT board. (J501/502)
(6) Check the connection of the carriage ribbon cable and the carriage board. (CN1/CN2)
(7) Replace the carriage ribbon cable.
(8) Replace the carriage board.
(9) Replace the PCNT board.
(10) Replace the purge unit.