I bought the dash center peace with the Garmin ball and a Nuvi 3790T.

Dremeled a small hole under the ball, so that the power adapter plug could be passed through. The hole ends up being bigger that the wire itself, due to the plug head. I used rubber gromets to fix that.

For the 3790t, the power plug, plugs into the cradle. The cradle then supplies power to the Nuvi. The cradle also uses power to run the cradle's built in speaker.

Although extremely clean, the biggest drawback to running the power cable under the dash is the reduction in traffic info reception. This really only matters if you live out in the country. When I'm on the DC beltway, traffic info comes in just fine. I haven't gone back in to see what I can do to fix it.

My thought is, I currently have the power cable bundled up, I'll want to unbundle it and string it out as much as possible.

Audio does not go through the car's sound system. However, with the Nuvi cradles's amplified speaker, directions come through LOUD and clear. I think my volume is currently set to 30%.

As far as power is concerned, I got a cigarette lighter socket with inline fuse and some wire splice connectors. Looked up the Radio wiring diagram, and spliced the socket to the switched power and ground wires.
Hope this info helps.

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'07 e83 x3
'91 e30 325i



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