Circuit/System Description
WARNING: This page is about a different car, the 2020 Buick Regal TourX, 2020 Buick Regal, 2019 Buick Regal TourX, and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The radio provides the microphone 2 with a supplied voltage on the microphone high signal circuit. When the microphone is in use, voice data from the user is sent back to the radio on the microphone low signal circuit. This microphone is used for driver side hands free calling enhancement, as well as a reference microphone for the primary microphone.