Car Stereos: car stereo, pioneer cd player, elantra

Question
I have a Pioneer CD player in my 2003 Elantra.  My boyfriend changed my car's battery and it hasn't worked since.  Do you know what is wrong and I how I might fix it?

Answer
Elizabeth, Your stereo probably requires a security code to activate it, so a thief cannot use it once they remove power from it.  You should consult the owners manual to see what steps to take to enter the code and get it working again.  If you cannot find your owners manual, you may be able to find an electronic version online, just do a search for your model number.. Hope this helps, Scott