Principles Of Operation

Information and Entertainment System

Principles of Operation

Audio Control Module (ACM)

The audio system can be operated while the key is in RUN or ACC. It can also be operated for up to one hour with the key turned OFF by pressing the ON/OFF control knob once. The Audio Control Module (ACM) sends AC voltage audio signals to the speakers. The ACM can produce its own DTCs, which can be communicated to the scan tool through the Medium Speed Controller Area Network (MS-CAN), or can be retrieved through the ACM self-test. The ACM communicates via the MS-CAN.

Voice Recognition System

The voice recognition system is comprised of the Speech Recognition Module (SRM) and the microphone. The voice recognition system controls various audio system functions and allows for mobile phone connectivity. Wireless signals are transmitted between the SRM and the customer Bluetooth device during a phone conversation. The microphone picks-up the voice of the vehicle occupant and sends an audio signal to the SRM. Incoming audio is sent from the SRM to the ACM, then to the vehicle speakers.

Antenna

The fixed-mast antenna receives AM/FM radio waves and sends them to the ACM via the antenna co-axial cable.

Steering Wheel Controls

The steering wheel controls consist of a series of resistors. Each steering wheel control switch function corresponds with a specific resistance value within the switch. When a switch is pressed, the ACM monitors the change in reference voltage to determine the requested function.

Audio Input Jack

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

Noise Suppression Equipment

The radio frequency suppression equipment reduces interference transmitted through the speakers by the engine ignition and electrical systems. When installing any new radio suppression equipment components, make sure that a good contact is made at all connections.