Car Stereos: 98 Plymouth Grand Voyager SE radio, plymouth grand voyager, sony head unit

Question
Hello, I recently installed a Sony Head unit on my minivan. After the installation The AM/FM stopped working.
Everything else works great MP3/CDs, What did I do wrong that made the AM/FM stop working? Oh yea, it doesn't work on ANY radio I put in there. Also the factory system had a wire hooked up to the back that says AMP on it, Is there a built in amp and do I have to hook that up too? Thanks

Answer
Hi Janio,

When you say it 'doesnt work', do you mean it's dead silent when you're on AM/FM or just static?  I'm trying to discertain whether it's a deck issue, or an antenna issue.  The 'amp' wire might be a factory amp (you'd know better than I -- does the vehicle have a 'premium' system?).  It could also be a antenna amplifier wire that requires 12V.  Test it to see if there's any power on it, and if not, you might need to hook the aftermarket deck's remote (blue) wire to the amp wire.

Justin