Canon MF720 Series Service Manual page 240

■ After replacing CIS units
1. AGC adjustment
1. Entering a provisional value
Change the foregoing values to "1,000".
• COPIER > ADJUST > CCD > LED-BW-R (Adjustment of LED light-up time (R) at B&W reading)
• COPIER > ADJUST > CCD > LED-BW-G (Adjustment of LED light-up time (G) at B&W reading)
• COPIER > ADJUST > CCD > LED-BW-B (Adjustment of LED light-up time (B) at B&W reading)
Change the foregoing values to "1,200"
• COPIER > ADJUST > CCD > LED-CL-R (Adjustment of LED light-up time (R) at color reading)
• COPIER > ADJUST > CCD > LED-CL-G (Adjustment of LED light-up time (G) at color reading)
• COPIER > ADJUST > CCD > LED-CL-B (Adjustment of LED light-up time (B) at color reading)
2. Adjust the white level in the following service mode.
• COPIER > FUNCTION > CCD > BW-AGC (CIS intensity adjustment in ADF (B&W))
• COPIER > FUNCTION > CCD > CL-AGC (CIS intensity adjustment in ADF (color))
3. If the operation was "successful", this procedure is completed. (There is no need to write the value on the service label.)
4. How to judge whether the operation was successful or failed
Whether the operation was successful or failed is not shown on the UI, so perform the following procedure to judge if
the operation was successful or failed.
B&W mode
• COPIER > ADJUST > CCD > LED-BW-R (Adjustment of LED light-up time (R) at B&W reading)
• COPIER > ADJUST > CCD > LED-BW-G (Adjustment of LED light-up time (G) at B&W reading)
• COPIER > ADJUST > CCD > LED-BW-B (Adjustment of LED light-up time (B) at B&W reading)
Check the foregoing values. If all of them remain "1,000", the operation result is judged to be "failed".
If the operation result is judged to be "failed", turn OFF and then ON the power, and execute COPIER > FUNCTION >
CCD > BW-AGC again.
Color mode
• COPIER > ADJUST > CCD > LED-CL-R (Adjustment of LED light-up time (R) at color reading)
• COPIER > ADJUST > CCD > LED-CL-G (Adjustment of LED light-up time (G) at color reading)
• COPIER > ADJUST > CCD > LED-CL-B (Adjustment of LED light-up time (B) at color reading)
Check the foregoing values. If all of them remain "1,200", the operation result is judged to be "failed".
If the operation result is judged to be "failed", turn OFF and then ON the power, and execute COPIER > FUNCTION >
CCD > CL-AGC again.
2. Automatic adjustment of the stream reading position
1. Entering a provisional value
Set the value of
• COPIER > ADJUST > ADJ-XY > STRD-POS (Adjustment of reading position at ADF stream reading)
to "-20".
2. Automatic adjustment of the stream reading position
Execute
• COPIER > FUNCTION > INSTALL > STRD-POS (Scan position auto adj in ADF mode)
If the operation was successful, write the value of STRD-POS on the service label.
3. How to judge whether the operation was successful or failed
Whether the operation was successful or failed is not shown on the UI, so perform the following procedure to judge if
the operation was successful or failed.
Check the value of
• COPIER > ADJUST > ADJ-XY > STRD-POS (Adjustment of reading position at ADF stream reading)
If it remains "-20", the operation is judged to be "failed".
If the operation is judged to be "failed", turn OFF and then ON the power, and execute COPIER > FUNCTION > INSTALL
> STRD-POS again.
3. Adjust the white level in the following service mode, and write the final setting values on the service label.
1. Enter the values in the following service mode items respectively.
• In COPIER > ADJUST > CCD > DFTAR-R, set "299".
• In COPIER > ADJUST > CCD > DFTAR-G, set "309".
• In COPIER > ADJUST > CCD > DFTAR-B, set "307" .
• In COPIER > ADJUST > CCD > DFTAR-BW, set "315".
2. Place a sheet of A4 or LTR blank paper (paper recommended by Canon) on the Platen Glass of the reader, and execute
• COPIER > FUNCTION > CCD > DF-WLVL1 (White level adj in book mode (color))
3. Place the same blank paper on the ADF, and execute
• COPIER > FUNCTION > CCD > DF-WLVL2 (White level adj in ADF mode (color))
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5. Adjustment