Tom, I am too much of a wimp to try to get at the Sirius module in my car to find out. But, I do have factory Sirius AND a factory CD changer, so is there any way I DON'T have the slave cable already connected to the Sirius module? I'm assuming that without the slave cable the Sirius and CD changer would not both work (they do). I have a 2005 X54.4.