I installed a brand-new Canon OEM printhead in the IP4000. I can now do a cleaning, then print a nozzle check where all of the colors and both B&W cartridges print well, except for the bottom half of the magenta stripe.
After numerous cleanings, deep cleanings, printer alignment, switching magenta cartridges (including a new one), the behavior remains the same - only the top half of the magenta strip prints on nozzle check.
If I try to print a page that includes color images immediately after a cleaning and nozzle check, the images print without magenta - they are entirely greenish-cyan.
If I then do a nozzle check print, there is NO magenta strip at all. If I clean the color nozzles several times, I again get the top half of the magenta strip on the nozzle check printout.
I have tried multiple cleanings, deep cleanings, head alignments, but nothing works to fix this error. Would be grateful for any help.