Controller System - Canon MF720 Series Service Manual

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.
2. 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.

Controller System

■ Main Controller PCBs
● Before Replacing the Main Controller PCB
Back up user data (settings, registered data, etc.) and service mode data for setting and registration after PCB replacement. Take
notes if data is unable to back up.
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5. Adjustment