I have a Hewlett Packard DeskJet 712C. Up until recently it's been a good ol' printer. Recently I've been having problems with the color and black ink. I changed them all, so all the cartriges are new...but all colors printed come out pink.
Sounds like your printers cartidge electrical system is fucked. That's the only thing I can think of. Most hp cartridges come with their own print heads... so that probably isn't the problem...
HP 51645A for the black ink and HP C1823D for the color. I'm pretty sure my black ink cartridge is empty, I'll need to buy a new one tomorrow, but the color one is new so all of the colors shouldn't be coming out pink.