[Sonics2042]

Is your car the anniversary edition? Mine was (also premium sound package) and it used european style wiring (aka common ground wiring). I had to re-wire all the speakers. If you have the premium sound package, then you will have a separate amp...if you take out the deck you will see it underneath... Just looks like a small grey box.

P.S. another fun thing to check is the ohm rating for the deck. The stock speakers are 2 ohm. Most decks put out 4 ohms. If you have 6 speakers and hook them all up, don't expect the deck to last long. What you can do, is hook four of em up and get some 4 ohm tweeters.

But most of this is only applicable if you have the premium sound system (six speakers + amp)

Thanks,
DoranW