New to the forums, so I apologize if this has been posted before or anything like that. I have a 2008 Grand Prix. My factory stereo died on me, so I purchased a Pioneer AVH-1400DVD unit to replace it. I got a mounting kit and a harness kit with the device to replicate the factory chimes, but I have had nothing but problems with it. The stereo would act weird, including staying on when the car was off (including when I opened the doors which should kill the retained power for accessories). The car has steering wheel controls and onstar, but I don't have any overwhelming desire to keep those features. I was wondering if anyone out there has hardwired an aftermarket stereo into their grand prixs, without a harness, and if so, if they have a wiring diagram and an idea of how well it worked out? I appreciate any help with this situation! Thanks!