apparently there is no GPS add on made for this unit or mine... from what i understand... the only difference between these units are small teaks... nothing major...
allthough the workaround i am looking into is the black box Gps systems... hard to find and very expensive.... they have a remote and a RCA out...
I just bought a used car that has this system installed. Under the setup screen there IS a "Navigation" tab. But it is greyed out, along with the Sirius tab. The car has the TV tuner installed, but no Sirius tuner. So the TV, DVD, TUNER and SPEAKER tabs in the setup menu all work. But not the Sirius or NAVIGATION. Hence the grey out in the setup menu. So I disagree with the above poster (unless the previous owner did some hack/tweak unbeknownset. But there is a "Navigation" option in the setup menu.
But if there is a tab in the setup menu for navigation, then there must be some component that is compatible with the VRX935D! I would like to know too. I can't find any info on it.