Adjust Print Quality : Clean the Print Head

Clean the Print Head
If your printouts become too light, or you see dark or light bands across them, you may need to clean the print head nozzles. Cleaning uses ink, so clean the nozzles only if print quality declines.
You can check for clogged nozzles before you clean them so you don’t clean them unnecessarily.
Note:
You cannot clean the print head if an ink cartridge is expended, and may not be able to clean it when a cartridge is low. You must replace the cartridge first.
Follow the instructions in these sections to check your print head nozzles and clean them:
Check the Print Head Nozzles
Clean the Print Head Nozzles