I am redoing my headliner and running a BT mic and saw this. It is broken and looks to be a coaxial style wire. Could not find any other end. Spent some time on wiring diagrams and got nothing.

 

I am not sure, But it looks like a power wire for a shot light ? Or for front over head lights above the mirror ? The reason I say this, I repaired a lot of old crown vics P71 retired police cars that were now taxis and thats where the power wire is for the spot lights are. It looks like the holes there are set up for a spot light to.
Oh i am a new member here, But a Long time stalker. I am a retired autobody guy and mechanic , But not retired by choice ! Had a bad accident working on my Dodge changing the trans fluid and the jack gave way, as it was new But defective.
So hope this helps you

 

I was wondering if it was for some type of light. Maybe a CB.

It went nowhere.

 

It could be an old satellite radio antenna wire. Previous owner might have removed all the components before you bought it, and left the wire. From what I can tell, it looks like one.