so I too suffered from the parasitic draw from the HFL not working on my 07 tl type s. I went to disconnect it, and then I saw this black wire plugged into this little module next to the HFL. What is it? I had no idea, so I left it plugged in. Any help would be appreciated. Thanks in advance.

 

Anybody?? Haven't found what this is yet.

 

Pretty sure it's the microphone.

I'm in the same boat as you. My HFL went out yesterday. Stuck at "Booting Up".

 

Pretty sure it's the noise cancellation mic.

 

Battery drained after two days of car sitting and wouldn't start, also disconnected the HFL, but couldn't get the cover to fit back in so
took the whole unit out. So we lose the voice recognition right?