Has my vehicle's SXM antenna gone bad?

Hi everyone, I'm brand new here and I'm hoping for some help with my vehicle's SXM radio. Someone from another forum (a non-SXM-specific one) sent me here.

This past Friday in my pickup - a Nissan Frontier - my SiriusXM radio started giving me a "No Signal" message all day long, even sitting in the middle of a large open parking lot. I took the "shark fin" off and looked it over, I didn't see anything that looked like it might be causing the antenna not to work. After I disconnected it, the display showed "Check Antenna" instead of "No Signal", so that makes me think that there isn't a problem with any of the wiring going to the radio itself.

I contacted SXM and they tried to refresh the signal, but that didn't do anything.

I'm tempted to try to replace the antenna with one from a junk yard and see if that fixes the problem, but I'm open to any other ideas people have.

Thanks in advance for any help!