Canon S820 User Manual page 133

White Streaks
Print the nozzle check pattern to check the ink output.
If a specific colour does not print in the nozzle check pattern, clean the print head.
The problem can also be resolved by aligning the print head. For details on print head
alignment, refer to
Printing the Nozzle Check Pattern
Print Head Cleaning
"Straight Lines are Misaligned".
Print Quality is Poor or Contains Errors
Troubleshooting
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