Lf / Eject Correction - Canon MP640 Service Manual

(3) LF / Eject correction

After replacement of the feed roller, platen unit, LF / Eject encoder, carriage encoder film, or logic board in repair servicing or in
refurbishment operation, perform the adjustment to maintain the optimal print image quality.
If the print quality is considered unaffected by replacement of those parts, it is not necessary to perform LF / Eject correction.
1) Print the LF / Eject correction pattern.
Click LF/EJECT of the Service Tool on the connected computer, select the paper source and the paper type, and print the
pattern. 5 sheets of A4 paper will be used for the pattern printing.
- Paper source: Select either Rear tray or Cassette.
- Media type: Select one from HR-101, GF-500/Office Planner, HP Bright White, and Canon
Extra/STEINBEIS.
2) When printing is finished, "A function was finished" is displayed on the computer, and the machine returns to be ready for
selection of another function.
3) In the printout, determine the Pattern No. in which streaks or lines are the least noticeable for the LF check pattern and the Eject
check pattern respectively.
(LF Pattern No. 0 to 4, Eject Pattern No. 0 to 4)
4) Select and set the correction values.
In the LF/EJECT Correction section of the Service Tool, select the Pattern No. (from 0 to 4) determined in step 3) for LF and
EJECT respectively, and click Set.
5) The selected LF and Eject correction values are written to the EEPROM, making the E-MIP correction value (which was set at
shipment from the production site) invalid.
Note: At the production site, the E-MIP correction, which is equivalent to the LF / Eject correction, is performed
using the special tool, and the E-MIP correction value is written to the EEPROM as the valid data.
When LF / Eject correction is performed, the LF / Eject correction values become valid instead of the E-MIP
correction value (thus, in the initial EEPROM information print, "LF = *" and "EJ = *" are printed, but the
selected values are printed after the LF / Eject correction).
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