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I bought a new radio (Sony Xplod CDX-GT550UI) for my car (2005 LX). Hooked everything up but when you turn it on it beeps, powers down and will not power on again.
I unplugged the antenna from the radio and it then it stays on and everything works fine (except you don't get any radio reception).
The support line at Crutchfield had me stick a hanger in the antenna input to see if that shorted it out. With the hanger inserted the radio turns on and works fine. Crutchfield said there's something wrong with my antenna and I need to have it replaced.

I'm not sold on the idea of replacing the antenna. My old factory radio works fine with the antenna. The support person at Crutchfield said that the factory radio wouldn't have problems because didn't have any mechanisms to protect it from the short circuit.

What are your thoughts on this? I appreciate the help!