Sorry for the lack of detail then... I am not sure what is a factory amp, so I guess I don't have one! My 2005 Vibe is a pretty basic model without eletric windows nor electric lock-door! The only fancy option on it is the AC I believe...

So there is apparently nothing to do? Is that bad for the radio/speaker when this startling bang happens?

Hi, I have just installed a new car stereo, Dual brand to replace my dead factory radio in my 2005 Vibe. To install it I have purchased a compatible harness and I have connected the wires myself as well as I could. It works quite great mostly: it replaces the original radio with more features for a ...