96RAMMED

I have a 96 Dodge Ram 2500 with the factory Infinity head unit with tape deck, and changer control. I plugged in the cord from the back of the deck to the CD changer and it will load and eject a cd and the sleeve. It will not go to cd mode when you press the mode button. My deck says disc on the # and #5 buttons, and it has the plug in for the cd harness on the back. Can anyone help me with why it will not work more than loading and ejecting the sleeve? Thanks in advance.

Mark