Workshop: Change Waste-Ink-Tank Canon Pixma iP4000: Important: Loss of warranty and your own liability
An exchange of a waste ink tank is usually accomplished by Canon´s service. It´s not an ordinary user-operation. It´s your personal responsibility, whatever might go wrong, it'll be on your head! And you lose Canon´s warranty.
We strongly advise you not to reset the waste ink collector´s counter without changing the sponges. Sooner or later the sponges might not be able to hold the waste ink, and it will pour out of the printer. What a mess!