Component Description: Radio

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.

In order for any radio to operate two essential parts are needed; the transmitter and receiver. The radio transmitter encodes a message (audio, video, or data) onto a sine wave and transmits it with radio waves to the antenna. The radio waves are transmitted from the antenna into free space.

The radio receiver antenna captures as much of the transmitters power as possible and supplies it to the radio tuner. The radio receiver also processes information from recorded playback media (e.g., CD player, IPOD, MP3 playback device, etc.).

After the radio receives and decodes the message the signal is amplified and sent to the speakers, remote amplifier, or headphones.

The operator interfaces with the radio system through the buttons and control knobs located on the Infotainment Faceplate Control Module or faceplate. The operator is able to control system power, volume, fade, balance, bass, and treble equalizations. When the operator turns a knob or pushes a button, a module in the faceplate sends a signal to the radio on a UART - based bus called CAN Graphical Interface (CGI). The CGI bus circuit is part of a wiring harness that connects the faceplate and radio.

The radio is located in the instrument panel center stack area, behind the faceplate, and is fastened to the instrument panel by fasteners. A rear bullet type guide pin is provided to aid in aligning the radio. A 44-way connector is the main connector for all radios. The navigation radio has an additional 20-way connector and a connector for the color display. The USB cable connection to the radio is the USB Mini - A type. Three separate coaxial cables connect to the radio, one each for AM/FM, XM (if equipped), and GPS.

Radio amplifier outputs to the speakers are protected from damage should speaker leads become shorted to ground or shorted to vehicle power. The radio will sense these conditions and shut down the amplifier outputs in a non-destructive manner. After the short condition is removed, the radio will return to normal operation.