I just bought a 98 GT, it has the mach 460 sound system in it and the guy before me put in a new kenwood single din head unit. My guess is they used the wrong wiring kit but I only have sound coming out if the tweeters and may or may not be coming out of the rear speakers, I have no sound coming out of my lower door speakers. My buddy with a 97 cobra has the same problem, does anyone know why this is? And how can I fix it?

 

You need the correct kit that has the wire that turns on the factory amps