KV-S7075C (serv.man2) - Panasonic Other Service Manuals Service Manual (repair manual). Page 110

110

Defects in the scanned 
image (ex: black or
white line or banding in
the image) 

1. Dust on ADF Glass (F) or ADF Glass
    (B)

Clean the glass surface.

2. Dust on the CIS lens inside ADF Glass
    (F) or ADF Glass (B)

Remove the glass, and then clean the lens.

3. CIS (F) or the image processing circuit
    for the front is broken. 

1. Execute "Image Sensor Output" in
    Sec. 9.3.6 to check the CIS condition.
2. Check the following connections and
    soldering condition:
   (1) CIS (F) to CN3001, CN3002, and
        CN3003 (CIS (F) RELAY Board)
   (2) CN3004, CN3005 (CIS (F) RELAY
        Board) to CN2008, CN2009 (CENTER
        Board)
   (3) CN2001 (CENTER Board) to CN1001
        (CONTROL Board)
3. Replace the CIS (F).
4. Replace the CIS (F) RELAY Board.
5. Replace the CENTER Board.
6. Replace the CONTROL Board.

4. CIS (B) or the image processing circuit
    for the back is broken.

1. Execute "Image Sensor Output" in
    Sec. 9.3.6 to check the CIS condition.
2. Check the following connections and
    soldering condition:
   (1) CIS (B) to CN3006 and CN3007 (CIS (B)
        LED RELAY Board)
   (2) CN3011 (CIS (B) LED RELAY Board),
        CN3009 (CIS (B) RELAY Board) to
         CN3024 (POWER RELAY Board) 
   (3) CN3010 (CIS (B) RELAY Board) to
          CN2011 (CENTER Board)
   (4) CN3023 (POWER RELAY Board) to
          CN2010 (CENTER Board)
   (5) CN2001 (CENTER Board) to CN1001
          (CONTROL Board)
3. Replace the CIS (B).
4. Replace the CIS (B) LED RELAY Board.
5. Replace the POWER RELAY Board.
6. Replace the CENTER Board.
7. Replace the CONTROL Board.

Scanning position is
shifted.

1.When reassembling CIS or mechanical
parts related to conveying documents,
re-adjustment is not done. 

Execute "All Position" and/or "Individual
Position" in Sec. 9.3.7 to adjust the
scanning position.

2. When replacing CONTROL Board, CIS,
    or mechanical parts related to
    conveying documents, re-adjustment is
    not done.

The document skews or
has a crease when
scanning.

1. Document Guides are not set correctly,
   according to the size of documents on
   the Hopper Tray.

Set the Document Guides correctly.

2. Rollers are dirty.

Clean the rollers.

3. Rollers are not attached to the default
    position properly when assembling.

Assemble the rollers properly again.

4. Rollers have reached their life
    expectancy.

Replace the rollers after inspecting them.
Note: