Printer with injection infuse error after printing 50 pages

Yesterday...
Some one come to my workshop with the printer ( Canon IP2770 with injection infuse ). The printer is error, he say this error appear after printing 50 pages, i say sure, if you print very much of pages, and you not open the tube cover of infuse, so the ink will late to out in the cartridge head. and print result not good and you get the white line in the print result.
For this error i do some job :
1. Open infuse tube cover
2. I clean head cartridge with clean tool from the printer i get from "printer properties"
3. I print the block picture/image 3 times or more
4. Success

I hope this experience will be help you