Scanning Problems - Canon PC-D320 Service Manual

PC-D320/PC-D340/FAX-L400 Chapter 4: Maintenance and Service

4.3.3 Scanning problems

• Faulty scanning (Evaluation criteria: Test print is good, but the copied image
is poor.)
• The document is not fed.
The document feed motor does not run. (Evaluation criteria: Check it
visually.)
(1) Check the connection between the document feed motor and the SCNT board (J505).
(2) Replace the document feed motor.
(3) Replace the SCNT board.
The document slips against the rollers. (Evaluation criteria: Check it visually.
Stretched copy image.)
(1) See page 4-3 and clean the document reading section.
(2) Replace the reading section's rollers.
The document does not separate. (Evaluation criteria: Check it visually.)
(1) Check whether the document feed motor is driving all the rollers.
(Check for any damaged gears or foreign matter stuck inside.)
(2) See page 4-3 and clean the separation roller and separation guide.
(3) Replace the separation roller and separation guide.
The scanner unit's sensors are defective (Evaluation criteria: The placed
document or transported document is not detected.)
(1) Check for any faulty sensors while executing the copying operation and test mode.
(2) Check the connection between the DS sensor, DES sensor and the SCNT board (J509).
(3) In test mode check whether the DS sensor and the DES sensor are operating correctly.
(4) Replace the DS sensor and DES sensor.
(5) Replace the SCNT board.
• The scanning image is abnormal. (Evaluation criteria: Check the copy
image's faults.)
Nothing is printed.
(1) Check the connection between the contact sensor and SCNT board (J506).
(2) Replace the contact sensor unit.
(3) Replace the SCNT board.
The image has vertical stripes.
(1) Clean the contact sensor's scanning glass, platen glass and white sheet.
(2) Check the connection between the contact sensor and SCNT board (J506).
(3) Replace the contact sensor unit.
(4) Replace the SCNT board.
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