2005 6.0 alt problems

Okay so, two nights ago I noticed my truck hesitate to start. I thought it might have been my fault due to not waiting for my glow plugs. After waiting a fee minutes it started right up. On my way to work the next morning my radio goes out and I get tbc fault across the odometer. 7 hrs later truck starts and then loses power almost instantly. After yanking the alt out of the truck and taking it to be tested I decide to buy another since it's fried. Go and install jump the truck and head home. On the way home radio goes out. While all this goes on I haven't once had my battery light come one. I noticed the green and red wire on the plug for the alt is a little frayed. I just bought a new plug and am about to throw it in. I read some where that's the wire that goes to the dash to tell the alt when to turn on and off. With the key in the on position and not running should that wire have voltage? The orange is showing 12.2 green and red is a dead 0. I need some help my truck is my only vehicle!!