Need help setting up a PS2 to an LCD TV

[helloimcdog]

I just bought an LCD 20" flat screen for my dorm room and am encountering difficulty setting my PS2 up properly. I can get video and sound fine, but I do not have any color on games, the set up screen, or DVD's.

Does anybody know if there is another cable I need to buy in order to get color out of my LCD TV. My PS2 works fine on my old school tv setup. Right now I have the the red, yellow, and white cables all hooked up in their appropriate slots and I have tinkered with them in just about every way possible and I still don't have color.

Any suggestions would be appreciated.