Im wanting to install an new stereo but i went to buy a wiring harness the guy at best buy told me it would blow my factory amp and disable my airbags because thier ran thru the factory deck... Is this tru? if so how can i bypass it..
2004 grand prix GT

Well he is lying. What package do you have? My car has no amplifiers, I have a wiring harness that was about 10 bucks had to find a remote but that was easy, FYI my airbag still seem to be fine, and everything else is ummm still ok. Kick him in the junk.

z

Ok i found out thats not true but crutchfield said that i would need a 80 dollar harness due to the chimes and system warning goin thru the radio. i know this is tru all my chimes do come thru the speakers.. Where did you get yer harness? and do your chimes still work...

No my chimes do not work anymore, thank god. I opted for the no chimes one for 2 reasons. One i always thougth there should be a way to turn off chimes because they annoy me, 2 it saved me a lotta money but is harder to work with because you must pick a remote up somewhere in the car.

Best Buiy.. I presume that's simular to Future Shop.. in that case.. kick him TWICE in the Junk.. Go to a place that specializes in audio/video.
I got my mp3 deck installed and it cost me 135 canadian for the door chime thingy.
Future Shop told me they use a whole new kit. I wanted to do it myself cuz I'm cheap. So 125 bucks for a mess of wires.. then I was reading how they bypass the air bag by jumping some wires in the fuse box.. umm this doesn't sound good.. then further on there's a caution about premature airbag ejection and the risk of getting umm.. dead from working under the dash and tripping it.. (Air bag replacement.. 3500 dolla)

The chime was soo easy. pull he dash. Get the right wire appaptor ofr the back of your deck (15 beans) and mach the colors.. litterally.. took me 30 minutes in the parking lot one night.

Tape the chime thingy though to tone it down.. mines damn loud.

Also...
If you need to run some power to your amp, run it along the rear of the fire wall. Then down near the brake fluid res and there should be a rubber plug that you can punch a hole into.
I ran 4 gage wire through it and it's a real beech trying to fat around if you accidentally pop the plug out.

Run the power wire on the opposite side of the remote and audio wires for your amp. It'll keep from getting noise (the whine noise) over the speakers when your rpms go up. YOu can hide the wires nicely using the plastic moulding that runs along the bottom of the door 'frame'. Then just run it up under the hinge in the rear seat so you don't see the cable.

As for ground.. just ground to the bottom of yout trunk. I would think 8aug would be enough.. I used 4 anyways. Scrape the paint off and secure the wire using a self tapping screw and a terminal end.

Make sure your not putting holes in your tank or anything equally silly.