Error 5100 appears on these Canon printers: MP140, MP150, MP160, MP190, MP210, MP220, MP800, MP810, MP170, MP180, MP450, MP460, MP830, MP970, MP980, MP240, MP250, MP260, MP270, MP480, MP500, MP510, MP520, MP530, MP540, MP620, MP550, MP560, MP610, MP630, MP800, MP810, MP830, MP970, MP980, MG2100, MG3100, MG4100, MG5100, MP640, MP990, MG5200, MG5300, MG6100, MG6200, MG8100, MG8200
It's a Carriage error.
- Look inside for a tiny object like a piece of paper, a staple...
- The purge cap (the white sliding mechanism that the print head parks to when it's not in use) may be not lubricated well enough . Lubricate the sliders with some white grease (don't get it on the small wipers or the black caps); this repair probably require to remove the right panel off of the printer to gain access to the purge mechanism.
- Clean the timing strip: there is a thin plastic strip running across the width in front of and below the drive belt: there are fine black vertical lines on this strip. If the strip gets a piece of crud on it, you get an error during the start-up sequence.Gently clean this strip with a damp lint-free tissue.
(you can see a transparent horizontal strip object which controls the movement of the printer head slots.)