Does anyone know which wire is the power source for the navigation unit in the trunk?

 

I don't know, but I hope you're not planning to tap into it to power Dom's unit. Dom recommends that you do not. I tapped the cig adapter/power outlet of the center console. Here are the instructions from my install.

If you still insist, PM gt1. I think he tapped into the navigation power source.

 

I actually dont' have Dom's unit. I bought an AVElectronics Unit (used), and the install that I found on the forum has the guy tapping into the Navi power source.

 

Well, if you need a switched 12V source, that cig adapter/power outlet of the center console will do it. Power will only be available when the car is on.

If you don't want to tap into wires, use a mini add-a-circuit and connect it to fuse #32 in the fuse box on driver's side. You'll just need to run wires from the fuse box to the trunk. That is still switched 12V.

If 12V is what you need, I would recommend you to do one of the above methods rather than using the navi power source.