Circuit/System Description

WARNING: This page is about a different car, the 2018 Buick Regal TourX and 2018 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

The Radio Ethernet AVB (Audio Video Bridging) switch communicates directly to each contributing Infotainment module. The Ethernet is used to transmit audio, video, data and control information between any devices attached.

The audio amplifier is a participant of the infotainment system and communicates directly with the Radio.

Each of the audio output channel circuits (+) and (-), at the audio amplifier have a DC bias voltage that is approximately one half of the battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound.