Canon MG6400 series Online Manual page 175

(4) Confirm the message, select Yes, then press the OK button.
The print head alignment sheet will be printed.
Important
Do not touch any printed part on the print head alignment sheet.
Be careful not to get the print head alignment sheet dirty. If the sheet is stained
or wrinkled, it may not be scanned properly.
(5) When the message "Did the patterns print correctly?" appears,
confirm that the pattern is printed correctly, select Yes, then press the
OK button.
5. Scan the print head alignment sheet to adjust the print head position.
(1) Confirm the message, then load the print head alignment sheet on the
platen glass.
Load the print head alignment sheet WITH THE PRINTED SIDE FACING DOWN
and align the mark
mark .
on the bottom right corner of the sheet with the alignment
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