Dell AIO Printer A-940 Color Problem

I would like to know how to fix my problem. The problem is that when I try to print a document or picture in color all that prints out is a blank piece of paper or in some cases writing so light its not readable. The color cartridge is half way full. I had to replace my black cartridge just to get stuff to print right and the other cartridge still had atleast 3 bars left. I hope this is a fixable problem. Because if I paid this much money for a printer then having to pay for cartridges this expensive that you cant even use fully I'm not going to be a very happy person. I'm using a Dell AIO Printer A-940. If someone would help me it would be much appriciated. Thanks in advance.