I got a question about the mach 460 is it only highs and mids i get no bass out of it at all. i mean i am not looking at a sub bass but i get nothing when the bass is hitting it is kinda dumb sounding. Sorry i can't explain much more.
if the factory radio is still in the car, then check your fuses. If it has been replaced then you need to pull the radio and make sure the blue/white remote turn on from the deck is connected to the blue amp power wire in the hrns.