My husband and I also have a 14 Silverado. Have started having issues with the XM radio (first), then the compass "stuck" on NORTH, now the red light for the OnStar.
According to OnStar, (last year) truck was in the water off the shore of Newark NJ. Just last week, called OnStar again and was told we were in Palisades NY on I-90 (Nope - in RI at the time!)
Took to the dealer (last fall), paid the $199 to have it "diagnosed". They told us the antenna (shark fin) was no good. OnStar ran a diagnostic when we called (last week) from the vehicle and said there was a "trouble code" and we should take it to the dealer.
Have done a bunch of research since then and found there was a "recall" (technical service bulletin) issued for the shark fin antenna on the 2015-18s. Unfortunately, it doesn't include the 2014s.
It seems the "fix" is to replace a poorly designed antenna. Fairly straight-forward (I won't call it "easy"). Remove the drivers side visor and grab handle, loosen the (left side of windshield) trim panel and headliner. One bolt holds it in place. Clean the area, apply a bead of caulking around the hole in the roof, and re-attach everything.
The challenge seems to be getting the new antenna.
Hope this helps!
