So one day i noticed on my Sync 3 system, the GPS logo had the red circle and a slash through it, indicating the GPS signal was lost. I recently updated the maps and wondered if it was a software glitch, as it was working correctly, until a few days ago. No glitch, suddenly the car is lost on the map and it's all over the place, no where near where I was at. A look at the wiring diagram and it shows the GPS antenna and satellite radio antenna are the same and there is a splitter for the two. I tried Sirius Radio, and bammo it's not working either. I decided to buy a new antenna, it was only $30, and will work on it this weekend after I pull the headliner. Wish me luck, I'll post the results.