my printer won't use it's black cartridge.

[thegeeet]

Hello, I've recently bought a canon pixma ip2600, I've had it about 2 weeks, now this isn't my first canon printer or printer in general and I've never come across a problem I couldn't fix myself yet. However my printer doesn't seem to be using it's black ink cartridge at all. It uses a black cartridge and a three in one colour cartridge, so that 2 carts in all. It came with a full set and I bought another full set at the time of purchase. I never expect the cartridges that come with a printer to last very long at all. I printed a bunch of stuff and the colour ink ran out, which I replaced with the other cartridge I bought, but the black ink in the printer ink monitor window was still reading as full. I've carried on printing and the second colour cartridge ran out, but the first black cartridge is still showing as completely full in the ink monitor window (that's the one the computer shows you on screen).
About half of the stuff I've prinited has been black and white photographs, so the natural assumption is that the printer has been using the colour cartridge to do all the black printing.
I've been through all the settings of all the programs I've used, looked in the control panel, tried everything I know. So there must be some setting I've over looked, or some stupid mistake I've made. Any ideas? Thanks in advance.
I tried printing out some black text using word pad and the text came out green, so the printer seems to be using the colour cartridge for that as well. I tried printing out a black and white photograph and that came out green as well, (because the colour ink is running out, everything is blue or green).

 

[Robotpixel]

It may just be a fault with the black cartridge, maybe it's not the first thing you want to try to resolve the issue, but if you cannot find any other sollution then you could just try buying another cartridge, the one your using may have faulty circuitry or something (if it has a chip that is).