anyone else have this problem? I have a 04 grand prix with an internal antenna. I'm wondering if the bypass is interfering with AM reception somehow. I cannot pick up a single station even in the city, and we have one of the most powerful AM stations in the country (700 WLW) nearby.

FM comes in fine.

did you connect the antenna wire from the d3 to the car's wire? there should be a blue wire in the harness you used to connect to the vehicle's wiring.