Car Stereos: Deck Install, door chimes, onstar

Question
I have a pioneer deck that is was going to install in a 2002 monte carlo. My car has all the options that run through the radio and if I dont buy that expensive integrated harness will anything real important be changed?

Answer
Hi Tyler,

If you have Onstar, and don't buy the harness, you'll lose it entirely.

If you have a factory amp and don't use the right adapter, you'll lose that too.

If you don't have either of those things, you'll lose door chimes.  You might think they're not important, but I'd hate to follow a curve on the highway at speed without realising that one of the doors wasn't shut, only to bounce it off another car.

Justin