2010 Yukon Bose issues

[Burk]

I have a 2010 Yukon with the Bose system purchased with the audio not working. I have swapped another brand new Bose amp thinking that was the issue. If I bypass the amp at the head unit I get sound but I’d like to make this work. There is one mystery plug I can’t figure out

 

[Big Mama]

Welcome to the forum from Virginia. One of the audio guys will chime in soon.