1999 Park Ave homelink wiring questions

I am swapping out the HOMELINK garage door opener in my cars, and the 1999 Park Ave that I got the new homelink unit out of has 1 more wire. My OLD setup has 2 wires (orange 12 volt, and black ground). The new ones has a BROWN wire. What does it go too? I think it is just to light up the LED in the center button, but I want to be sure before I randomly hook it up.

Thanks

I don't find this on any schematics I have. However all the lighting schematics show brown leads as hot wire to all the lights else where in the chassis. Seems logical to think the same for this brown one.