I have an Australian 05 GS300 with a Gen4 ML stereo. I am trying to hook an aftermarket bluetooth adapter using the second cd changer port. There is already a plug with 2 wires plugged in the Port. I unplug it and plug the bluetooth adapter in, the cd button allows me to switch to cd changer 2 and play music, but the head unit says there's an error and Aircon won't work, so I piggy back the two missing wires into the bluetooth audio plug and the radio works fine again but the bluetooth adapter now doesn't. Does anyone have any ideas? What are the two wires? Light Green and blue.
Thanks

That seems odd.
I put a bluetooth adapter in my 08 GS460 but used a splitter adapter as there was already a plug there.
The 08 already has an Aux input switched on the DISC button though, but this no longer works with the bluetooth installed.
I just went the cheap route with a bluetooth adapter as I wasnt even sure it would work. I'm already looking for a replacement though as the one I got sounds average through the ML and doesn't display track information

I used the GROM kit, and it works flawlessly

Does the GROM (I assume BT3) give track information on the display?
What is the audio quality like compared to CD?