Da240

Ok so I was driving and the car just just died. Got the battery test it needed to be charged. Got it charged, then I had the alternator tested, bad alternator. Put the new one in from advance took it right back to have the system tested. Again bad alternator. Mind you since i've got the swap done over a year ago, the plug going into the alternator has never been plugged up. I thought it was another plug hanging like the rest. So after some research I learned the plug gives off 12V which it does, but the small white and red wire that goes to the charge light isnt giving off anything and is running to yet to another plug thats not connected to anything. Could this be my problem. Please help!!!