Hi poloace,
Please makre sure that all of the ink tanks in your PIXMA MG6120 have ink.
After making sure that they do, please perform a few printhead cleanings. To perform cleanings, please follow these steps:
1. Press the <HOME> button on your PIXMA MG6120.
2. Select Maintenance and press <OK>.
3. Press <OK> on Cleaning.
4. Press <OK> on Yes.
5. Press <OK> on Yes.
After a few cleanings, please print another Nozzle Check.
If the Nozzle Check still prints incorrectly, please contact live technical support . There is NO charge for this call. Real time feedback of a live technical support call would be very beneficial in this case.
Please dial 1-866-261-9362, Monday - Friday 10:00 a.m. - 10:00 p.m. ET (excluding holidays). A Canon technical support representative will be able to resolve this issue faster.