Adjustment At Parts Replacement; Document Exposure / Feed System - Canon MF720 Series Service Manual

Adjustment at Parts Replacement

Document Exposure / Feed System

■ After Replacing the ADF Units
1. 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))
4. Place a sheet of A4 or LTR blank paper (paper recommended by Canon) on the Platen Glass of the reader again, and
execute
• COPIER > FUNCTION > CCD > DF-WLVL3 (White level adj in book mode (B&W))
5. Place the same blank paper on the ADF again, and execute
• COPIER > FUNCTION > CCD > DF-WLVL4 (White level adj in ADF mode (B&W))
6. If the operation was successful, write the setting value on the service label.
7. Whether the operation was successful or failed is not shown on the UI, so perform the following procedure to judge if
the operation is successful or not.
• COPIER > ADJUST > CCD > DFTAR-R (Adjustment of shading target value (R) at ADF reading)
• COPIER > ADJUST > CCD > DFTAR-G (Adjustment of shading target value (G) at ADF reading)
• COPIER > ADJUST > CCD > DFTAR-B (Adjustment of shading target value (B) at ADF reading)
Check the foregoing values, and if all the values remain the same with those you entered, the operation result is judged
to be "failed".
8. If the operation result is "failed", turn OFF and then ON the power, execute
• COPIER > FUNCTION > CCD > DF-WLVL1 (White level adj in book mode: color)
and then execute
• COPIER > FUNCTION > CCD > DF-WLVL2 (White level adj in ADF mode: color)
again.
9. Checking the value of DFTAR-BW
Check the value of
• COPIER > ADJUST > CCD > DFTAR-BW (Adjustment of shading target value (B&W) at ADF reading)
If the value remains the same as the value you entered, the operation result is judged to be "failed".
10. If the operation result is "failed", turn OFF and then ON the power, execute
• COPIER > FUNCTION > CCD > DF-WLVL3 (White level adj in book mode (B&W))
and then execute
• COPIER > FUNCTION > CCD > DF-WLVL4 (White level adj in ADF mode (B&W))
again.
2. ADF geometric adjustment
1. On an image copied using the ADF, check the non-image width in the X and Y directions and the expansion/contraction
in the X direction.
In the case of E353MGMH, perform 2-sided original reading from the ADF.
If adjustment is needed, enter necessary adjustment values in the following service mode:
• COPIER > ADJUST > ADJ-XY > ADJ-Y-DF (Adj img pstn in ADF mode:horz scan)
• FEEDER > ADJUST > DOCST (Fine adjustment of VSYNC timing at ADF reading [front side])
• FEEDER > ADJUST > DOCST2 (Fine adjustment of VSYNC timing at ADF reading [back side])
• FEEDER > ADJUST > LA-SPD (Fine adjustment of magnification ratio in vertical scanning direction at ADF stream
reading [front side])
• FEEDER > ADJUST > LA-SPD2 (Fine adjustment of magnification ratio in vertical scanning direction at ADF stream
reading [back side])
2. If you enter adjustment values, write the final values on the service label.
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5. Adjustment