Note: The images used below are of a Canon iP4000 printer.
With the printer powered off, open the paper output tray and top cover.
Note: If the printer is powered on and the top cover is opened, the print head holder will move automatically, possibly causing injury or damage.
<1> White grease on the metal shaft <2> Timing Film slit strip
Note: When cleaning the printer, do not touch the shaft, or the film. If you spread the white grease on the shaft to other parts or touch the film, it may cause damage to the printer. If you touch the grease, after washing your hands, continue cleaning.
Using a cotton swab, carefully clean any ink on the protruding ribs (indicated by arrows) and any ink around them.