Canon MultiPASS C755, Service Manual, Page: 82 / 143

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MultiPASS C755 Chapter 3: Maintenance & Service
4.3.2 Printing problems
• Faulty printing (Evaluation criteria: Test print is no good.)
• The paper is not fed properly. (Evaluation criteria: Look at the actual unit.)
The Paper feed motor does not run.
(1) Check the connection from the paper feed motor to the PCNT board (J202).
(2) Check the paper feed motor's resistance. 2.4
Ω
/1 phase is normal. (
Fig. 3-11
)
(3) Replace the paper feed motor.
(4) Replace the PCNT board.
The paper is not picked up from the auto sheet feeder.
(1) Check parts in the paper feed motor drive switching mechanism for abnormalities.
(2) Make sure that the ASF gear is attached correctly.
(3) Replace pickup roller ass’y.
(4) Replace PCNT board (Faulty PRS or PES).
• The printing operation is abnormal.
Nothing is printed.
(1) Remove the BJ-cartridge and re-install it.
(2) Execute cleaning five times, and try printing again.
(3) Replace the BJ cartridge.
The carriage motor does not run.
(1) Check the connection from the carriage motor to the PCNT board (J203).
(2) Check the carriage motor's resistance. 3.3
Ω
/1 phase is normal. (
Fig. 3-11
)
(3) Replace the carriage motor.
(4) Replace the PCNT board.
Figure 3-11 Paper Feed Motor/Carriage Motor/Document Feed Motor Connector
Paper feed motor connector
To paper feed motor
Carriage motor connector
To carriage motor
Document feed
motor connector
To document
feed motor
1
4
1
4
1
4
1-3 : 2.4
Ω
2-4 : 2.4
Ω
1-3 : 3.3
Ω
2-4 : 3.3
Ω
1-2 : 15
Ω
3-4 : 15
Ω