Can you do a print out the nozzle check pattern?
It should look like this:
If it looks like this, then it needs cleaning
Is the printer still under warranty? How many sheets total (approx) have you printed? How long have you been using the printer? Do you go for long periods of not printing out anything?
Follow these steps to clean the print head:
1. Make sure the all-in-one is turned on but not printing.
(If ink is low, you may need to replace the low ink cartridge before cleaning the print head.)
2. Load a few sheets of plain paper in the main tray.
3. Press the Home button and select Setup.
4. Select Maintenance.
5. Select Head Cleaning.
6. Press Start.
Cleaning takes about 2 minutes. When it's finished, you see a message on the display screen.
Never turn off the all-in-one during a cleaning cycle or you may damage it.
7. When you see this screen, select Nozzle Check, then press Start to confirm that the print head is clean.
Examine the nozzle check.
If the nozzle check has no gaps, you're done. Select Finish Nozzle Check.
If you see any gaps or missing sections or if the page is blank, repeat the cleaning process by selecting Head Cleaning and then pressing Start.
* If necessary, repeat the cleaning process up to 4 times.
* If repeated cleanings don't help, you can also turn off the all-in-one and wait at least six hours. Then print the nozzle check (by selecting Nozzle Check from the Maintenance menu) and, if necessary, perform the head cleaning again.