Canon FAX-B820 Service Manual page 11

· No sound from speaker
(1) Check the connection between the speaker and the SCNT board (J152).
(2) Replace the speaker.
(3) Replace the SCNT board.
2.3.2 Printing failure
Printing failure (ajudgement criterion: copy failure)
· Paper not properly fed (ajudgement criteria: check machine)
Paper feed motor is not working.
(1) Check the connection between the paper feed motor and the SCNT board (J302).
(2) Replace the paper feed motor.
(3) Replace the SCNT board.
Paper not picked up from the ASF
(1) Check for any abnormalities in the paper feed motor drive switching mechanism.
(2) Check that the ASF assembly drive gear has been properly attached.
(3) Replace the pickup roller unit.
(4) Replace the SCNT board (paper edge sensor or pickup roller sensor failure).
· Printing operation abnormality
Nothing is printed (blank page)
(1) Take out the BJ cartridge and install it again.
(2) Clean the BJ cartridge five times.
(3) Replace the BJ cartridge.
(4) Check the connection between the carriage ribbon cable and the SCNT board (J251).
(5) Replace the SCNT board.
Carriage motor does not move
(1) Check the connection between the carriage motor and the SCNT board (J301).
(2) Replace the carriage motor.
(3) Replace the SCNT board.
·Print quality defect
·Printing quality unstable
If the printed image has white streaks or spots, head cleaning should be performed.
When the following sequence is performed, the BJ cartridge head will be cleaned automatically.
Press the Function button, cleaning button and then the START/ COPY button.
Head cleaning required
The print head nozzles sometimes become clogged with paper dust or ink, etc.
In such cases, head cleaning should be performed.
When the following sequence is performed, the BJ cartridge head will be cleaned automatically.
Press the Function button, cleaning button and then the START/ COPY button.
1-6