I have a 2008 F-350 Lariat with a standard radio, cd player, NO nav. My Sub doesn't seem to be working. I've installed a new amp with no better results. I recently got a similar radio out of a 2012 King Ranch. All the connections are the same except for the 2012 radio has a yellow single round plug in the back of it, near center, side to side. My original radio doesn't have this plug.

The newer 2012 radio works except for the Satellite radio. I know I have to do an ESN transfer, however, when I select Satellite radio, an "Antenna Fail" sign comes up on the display. I don't want to spend $70.00 on an ESN transfer until I know that it will work for sure. Does anyone know what the yellow plug is for? Is it the antenna plug for the satellite? My original radio didn't have it but yet the satellite worked perfect. Has anyone else had sub problems?

Thanks