There are a few issues people have been having with baking hfl acura tl that you should be aware of.

Take a look…

HFL Not Working – AcuraZine Community

http://acurazine.com Jun 23, 2013

I have a similar problem – my bluetooth HFL worked great for years in my 06 TL but then stopped working about 2 months ago – at first I assumed it was my iPhone but after talking with Acura phone service they suggested trying my wife phone and when … Two options: one is to remove the HFL module, pull out the circuit boards and bake them in the oven @ 385*F for 9 minutes, per post #507+ in this thread: http://tl.acurazine.com/forums/showthread.php?t=792642.