Canon i 850 - Manual (Page 78)

Print Head Cleaning 78
Routine Maintenance
4
Select the ink nozzles to be cleaned, and then click Execute.
All Colors: All nozzles
Black: Black ink nozzles
Color: Color ink nozzles
5
When the confirmation message is displayed, click OK.
Macintosh
1
Ensure the printer is on.
2
Open the Page Setup dialog box.
The Page Setup dialog box can normally be opened by selecting Page
Setup... in the File menu.
3
Click the Utilities button to open the Printer Utility dialog box.
4
Select Cleaning from the pull-down menu, and then click the Cleaning
icon.