The model you have has a seperate Print Head from the ink cartridge. You can buy them from HP for about 35 bucks.
here is a link.
http://www.shopping.hp.com/webapp/sh...&lang=en&cc=us
Each color cart has it's own Print head, so if the printer gives you any more information on WHICH print head is bad, you'll want to pay attention so you don't replace a good print head.
FYI, the Print head is what takes the ink from the cartridge and sprays it on the paper.