Principles of Operation

Information and Entertainment System

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The audio unit can be powered up when the key is in RUN, ACC, or START. The audio unit provides audio signals to the speakers, thus producing sound. The audio unit directs the audio signals to the speakers through separate positive and negative circuits for each of the 4 audio channels: LH front, RH front, LH rear, and RH rear. The audio unit provides internal circuit protection for shorts to ground and shorts to battery.

The satellite audio system consists of a Satellite Digital Audio Receiver System (SDARS) module, a satellite radio antenna, and an antenna cable. The satellite radio antenna receives digital audio signals and sends them to the SDARS module, where the signals are converted and sent to the audio unit. The wake-up signal for the SDARS module is sent from the audio unit through a dedicated Medium Speed Controller Area Network (MS-CAN).

The audio input jack allows for a portable MP3 player to be connected to the vehicle audio system. When a portable MP3 player is connected, audio from the MP3 player can be played through the vehicle speakers.