So I have aquired and XC-540 that has been sitting for probably a year. I've gotten all heads to come back except magenta. It's won't even try to print 1 single line. This has got me thinking it's something else because I took the head out and flushed it with cleaning solution and could see the nozzles squirting. Is there something or someway else to test and make sure it's electronically working? Is there a fuse that controls each head maybe? I pulled ink through the damper with a syringe so ink seems to be moving through the lines. Anyone have any ideas I could try?