So we all know that Yellow is constant 12v and red is switched 12v.
Which one is actually expected to supply power to the unit for the internal speaker amp?
I have seen some radios claim that the primary power comes from the constant 12v, and the switched 12v is only used as a signal wire to tell the radio to turn on. Much as the 12v illumination wire would signal dimming of the display.I have also seen some radios that claim that the constant 12v source is used for memory backup only, and the switched 12v carries the power to operate the radio.
I have installed the z130bt in my 2005