PeachParts Mercedes-Benz Forum - View Single Post - w211 bluetooth options-opinions welcome

jay_bob · #4 06-05-2021, 08:45 PM

My son's 2008 E320 has the built in handsfree cell phone (the stick at the back of the cup holders) and the Aux jack in the glove box.

The handsfree interface is only for calls (Headset protocol), it will not handle streaming (A2DP protocol).

My work around was to find a Bluetooth audio to line level dongle. I found it on eBay and spliced the audio into the Aux connection on the back of the radio (it's on an independent 3 pin connector). I got power for it from the cigarette lighter socket.

If you do this yourself I recommend adding a switch to turn the thing off when you don't want it to stream (i.e. you are listening to the radio instead). Otherwise your phone will still connect and stream even though you are not listening to it.

If you have one of the older 211s that did not have the factory cell interface then you're pretty much out of luck trying to even get hands free cell phone to work.

If you have the 'iPod interface kit' that uses the Aux path to the radio (my other son's 2008 ML320 has this). This is why the stereo has to be on 'Aux' mode for it to work. It is very much an after thought. The control box has a connection to the body CAN bus so that it can talk to the instrument cluster and steering wheel controls.