Circuit/System Description
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The radio provides six discrete audio output channels to the amplifier. Each channel includes two wires consisting of a plus (+) and minus (-) circuit. During normal operation, the radio applies approximately 4 volts on the audio output circuit to the amplifier. The amplifier amplifies the input to ten discrete audio output channels connected to speakers.
In order for the speaker to produce sound, the amplifier raises the voltage on one speaker terminal and lowers the voltage on the opposite speaker terminal, then quickly reverse the polarity. The constant switching of the electrical signal causes the voice coil and speaker cone to move rapidly in two directions. The movement of the speaker cone produces sound.