If ink is allowed to fall below the recommended minimum levels on the bottles it may be possible for air to get into the tubing and ultimately into the cartridge. This will prevent the printer working (colours completely missing on nozzle checks).
This is completely different to the tiny amount of air in the tube during first install and the air needs to be removed to
Press the ink button on the printer and remove the cartridge set.
Use the syringe and needle provided. Push the needle through the rubber grommet.
Draw the syringe back until ink only (no air bubbles) is being pulled into the syringe.
Replace the cartridge set into the printer and follow the procedure on page 5 for charging the printhead again.
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