Canon MG6400 series Online Manual page 191

(1) Make sure that the paper feed roller has stopped rotating, then follow
the message to load three or more sheets of A4 or Letter-sized plain
paper in the front tray.
(2) Open the paper output tray gently.
(3) Press the OK button.
The machine starts cleaning. The cleaning will be complete when the paper is
ejected.
(4) When the completion message appears, press the OK button.
The screen will return to the Maintenance screen.
Note
Press the HOME button to exit Setup and display the HOME screen.
If the problem is not resolved after cleaning the paper feed roller, contact the service center.
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