Join Date: Jan 2008
Location: Fallbrook, CA, USA
Re: 2820 and BC-3 Bluetooth
What I am saying is that the GPS has no way to interface with the microphone on the intercom/headset. The GPS reports no microphone when you connect via bluetooth. It's not meant to connect that way. It's meant to be used as a standalone configuration in a car where you can place the external Garmin microphone that connects to the GPS for user input.
The intercom/headset works just fine with the HF820 connected to the phone jack on the intercom panel. That's why I use it. If you want to use bluetooth on the GPS then you will have to use the Garmin external microphone too. Having two mics in one helmet and two pairs of wires could get messy, which is why everyone else is using the HF820.
It might be possible to connect the microphone in your existing helmet to the GPS external microphone input, but them you'd have to hack the intercom wiring. Even then, you'd have two devices connected to one microphone and I have no idea how well that might or might not work. It wasn't worth pursuing as far as I was concerned since the HF820 & BMW cable could be purchased for less than $50 and is a proven solution.
2006 Magnesium Black Metallic K1200LT (sold - sigh)
1996 Sinus (aka Cirrus) Blue Metallic R1100RT