Canon PIXMA MX860 series, Service Manual

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2-4. Troubleshooting by Symptom
Symptom Solution
Faulty operation The power does not turn on.
The power turns off immediately
after power-on. (1) Confirm connection of the power supply unit:
- Harness and connector conditions
(2) Replace the following item(s):
- Logic board
- Power supply unit
- Panel board
A strange noise occurs. (1) Examine and remove any foreign material or paper
debris.
(2) Replace the following item(s):
- The part generating the strange noise
- Logic board
The LCD does not display properly.
A portion of the LCD is not
displayed.
The display flickers. (1) Confirm cable connection (LCD FFC and panel
harness):
- Harness and connector conditions
- No cable breakage, etc.
(2) Replace the following item(s):
- LCD FFC
- LCD viewer unit
- Panel board
- Logic board
Paper feed problems (multi-feeding,
skewed feeding, no feeding). (1) Examine and remove any foreign material or paper
debris.
(2) Confirm the PF rear cover and the cassette
conditions.
(3) Confirm cable connection.
(4) Replace the following item(s):
- ASF unit (for paper feeding error from the rear
tray)
- PF pick-up unit (for paper feeding error from the
cassette)
- DF unit (for document scanning error)
- PE sensor board
- Pressure roller unit
- Cassette unit
Faulty scanning (no scanning,
strange noise). (1) Confirm cable connection (scanner motor cable and
CIS FFC):
- Harness and connector conditions
- No cable breakage, etc.
(2) Replace the following item(s):
- Scanner unit
- Logic board
Unsatisfactory print quality No printing, or no color ejected.
Faint printing, or white lines on
printouts.
Uneven printing.
Improper color hue. (1) Confirm the ink tank conditions:
- Confirmation of the air-through of an ink tank
- Re-setting of an ink tank
(2) Remove foreign material from the purge unit caps, if
any.
(3) Perform cleaning or deep cleaning of the print head.
(4) Perform print head alignment.
(5) Replace the following item(s):
- Print head
*1
, and ink tanks
- Logic board
- Purge drive system unit
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