Ok so I have a 2002 Trailblazer and when I purchased the car the factory radio was cut out. So I rewired it so I could hook the radio back up and when I plug the factory radio back in, the display doesnt come on but the lights for the keys on the radio do and my car wont crank or start. The dash comes on but glitches and the gauges dont work. It kinda sounds like the dash keeps resetting or something. When I unplug the radio the car works just fine. It will start up and have no problems. But when plugged in nothing works.