I'm looking to put a aftermarket CD player in my 04 cavalier and I already purchase the harness, adaptor, and the kit for the car. To my understanding I must have a door chime module, why is that? I would like any answer to this question.

swissbeats

Who ever told you that you need the door chime module is f'ing crazy. You do not need the chim module, unless you like those damn chimes. I have an '05 with a Pioneer hu, works fine for me with out the chim module. Wire to wire. Your adaptor from stock to hu, color wire to color wire. The power antena wire do not worry about that. Also there may be a couple other wires that have no were to go, do not worry about those either.

Almost ofrgot, you will need to find a 12V pwer source for the hu. Me, I used the fuse box, old school way.

Ok here's the thing with the door chime module. If you take your stock radio out you will lose the following, seat belt warning(big one), headlight waring(another big one), 12volt acc power(more convienent), and RAP(I love this). In other words do you need it, no. But read this. Your in a hurry to get somewhere and you forget to put you seatbelt on cause your in a rush. Cop pulls you over and gives you a tcket. That sucks. Now if you had the harness with the door chime module, you would be ok. If you have anymore specific questions send me an e-mail. kassdog108@aol.com

Wow that is funny. I do not have the module for the door chimes. Yes I have an after market hu, I still have all the warning lights. Just no chimes. 12acc power how is this lost (if I am understanding you correctly). My acc still works fine.