Thanks to scot3818, Kmartin, and all others who posted this data. I just got my MP3 player working on my '06 Tribeca.
A few things to clarify, I was a bit confused on how to enable the RSE without hooking up a power/ground to my MP3 player.
KMartin's post was a bit confusing as it kept referencing pin numbers on that connector and I don't know what pin is pin1 vs. pin16. So this is what I did to enable the RSE without having a power/ground connection to the MP3 player.
Just hook up the left, right and ground to the stereo as in scot3813's PDF File. Then, I just added another ground wire from the back of the stereo (where I attached the MP3 player's cable ground) to the chassis of the radio. Thats it. Just one extra wire. Works great. When I want CD, just press the CD button on the radio, AM press AM. MP3, press RSE. Easy.
So now that i've got this all hooked up, the audio out of my MP3 player is not as loud as the AM/FM Radio. I have the output volume of the MP3 player max'd. But its not as loud at the same radio volume as the AM/FM or CD modes.
Does anyone know of a volume booster that I can put inline with my MP3 player?