I'm not sure. I just know that the orange wire in the Fakra cable is for the button illuminations on the Dynavin (there is a red wire that is used as the power wire for the Dynavin). And in talking with Jeff from J&T Distributing where I bought my Dynavin from, he told me that the plug where the Fakra cable plugs into in the back where the nav radio is located (step #49) does not provide power for the orange wire on the Fakra cable for the button illuminations. Possibility is that the stock nav monitor uses a different wire from the harness for the MID connection located in the front dashboard (just a guess)? And so the easiest way is to use the red wire in the Fakra cable that is used to power the unit and tap the orange wire into it as a power source.

The other option if you want it to be truly on/off for the button illumination is to find a different power wire source to tap into that is sync'ed with the on/off interior lighting for day/night driving. I didn't bother with this approach because I wanted to keep the Fakra wires fully contained within itself, rather than having 1 wire lead out to somewhere else (plus it was less work this way to just tap the orange wire into the red wire)