DIAGNOSIS The printhead nozzles are clogged. Dried ink is blocking the fine channels, causing misdirected ink drops.
FIX Run the deep cleaning utility. On the printer's screen, go to Setup > Maintenance > Deep Cleaning. Select the color group showing issues, or run for all colors. This uses a significant amount of ink. Print a nozzle check pattern after to verify results.
IF THAT DIDN'T WORK Perform manual printhead cleaning. Dampen a paper towel with distilled water. Place it in the tray. Move the printhead to the center position (via printer maintenance menu). Gently dab the printhead nozzles onto the damp towel for 60 seconds. Do not rub. Run a nozzle check.
HEADS UP Frequent deep cleaning wastes ink. If clogs persist after two attempts, the printhead may be damaged. Using non-Canon ink significantly increases clogging risk.