The waste ink absorber is almost full. Press the printer's RESUME

Yes, you can do it at home (if not under warranty).
Open the top cover and look for a place where there is a lot of semi-dry ink. Remove this sponge carefully and then (after reassembling your printer) follow the steps below to reset your printer:

1) Power off printer
2) Hold RESUME button then press and hold POWER.
3) Hold POWER and Release RESUME.
4) Press RESUME twice then release both POWER and RESUME buttons.
5) When the indicator lights steady, press RESUME 4 times.
6) Press power to set data.


WARNING: This procedure is followed by experienced service personnel to solve this problem but, if followed incorrectly, can render YOUR PRINTER USELESS. I post it here for your reference only. Try this at YOUR OWN RISK.

I can tell you that you need a new ink absorber,QY5-0144-000 around $10.00. and you need to remove the top cover and then lift the print engine up and install the new absorber on the bottom. But as a Canon dealer I can't give you the steps to reset the waste ink counter.