Principles of Operation

Information and Entertainment System

Principles of Operation

ACM (Audio Front Control Module) (Early Build)

The audio system can be operated with the ignition in RUN or ACC. It also operates in OFF for up to one hour by pressing the ON/OFF control knob once. The ACM (Audio Front Control Module) sends AC voltage audio signals to the speakers and produces its own DTCs. DTCs are retrieved through the Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair, or communicated to the scan tool through the Medium Speed Controller Area Network (MS-CAN).

ACM (Audio Front Control Module) (Late Build)

The audio system can be operated with the ignition in RUN or ACC. The ACM (Audio Front Control Module) sends AC voltage audio signals to the speakers and produces its own DTCs. Late build ACM (Audio Front Control Module) s do not communicate with the scan tool. DTCs can only be retrieved through the Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair.

Antenna

The fixed-mast antenna receives AM/FM radio waves and sends them to the ACM (Audio Front Control Module) via the antenna co-axial cable.

Audio Input Jack

The audio input jack allows for a portable MP3 audio device, such as an iPod(R), to be connected to the vehicle audio system utilizing a 1/8 inch (3.175 mm) audio jack. When connected, the vehicle speakers output the audio from the MP3 audio device. Only the speaker volume can be controlled with the vehicle audio system and all other functions such as seek, fast forward, and pause must be carried out on the device itself.

For early build vehicles without the Bluetooth Hands-Free System, the audio input jack is hardwired to the ACM (Audio Front Control Module). For early build vehicles with the Bluetooth Hands-Free System, the SRM (Speech Recognition Module) receives hardwired audio signals from the audio input jack and sends them to the ACM (Audio Front Control Module).

For late build vehicles without SYNC(R), the audio input jack is hardwired to the ACM (Audio Front Control Module). For late build vehicles with SYNC(R), the APIM (Accessory Protocol Interface Module) receives hardwired audio signals from the audio input jack and sends them to the ACM (Audio Front Control Module).

Audio Signals

Stereo signals contain left and right channel information, and are used for most audio signals. Mono signals do not contain left or right channel information.

Bluetooth Hands-Free System (Early Build)

- A mono signal is used for the microphone input to the SRM (Speech Recognition Module). The mono signal is also used for voice prompts, ringtones, and any audio received through a connected mobile phone. The SRM (Speech Recognition Module) outputs these audio signals to the ACM (Audio Front Control Module). The mono and stereo outputs from the SRM (Speech Recognition Module) utilize the same circuits.

SYNC(R) (Late Build)

- A mono signal is used for the microphone input to the APIM (Accessory Protocol Interface Module). The mono signal is also used for voice prompts, TTS (Text-To-Speech), ringtones, and any audio received through a connected mobile phone. The APIM (Accessory Protocol Interface Module) outputs these audio signals to the ACM (Audio Front Control Module). The mono and stereo outputs from the APIM (Accessory Protocol Interface Module) utilize separate circuits.

- A digital signal is used to transmit data from a media device connected through the USB (Universal Serial Bus) port to the APIM (Accessory Protocol Interface Module). The APIM (Accessory Protocol Interface Module) converts the digital signal to analog and relays it to the ACM (Audio Front Control Module).

- A wireless signal is used to broadcast audio signals from a Bluetooth device to the APIM (Accessory Protocol Interface Module). The APIM (Accessory Protocol Interface Module) converts the wireless audio signal to analog and relays it to the ACM (Audio Front Control Module).

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 good contact is made at all connections.

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 (Audio Front Control Module) monitors the change in reference voltage to determine the requested function.

Bluetooth Hands-Free System (Early Build)

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

SYNC(R) System (Late Build)

The SYNC(R) system allows interaction with several types of customer devices, including mobile phones and media devices. The APIM (Accessory Protocol Interface Module) contains an on-board Bluetooth chipset which enables certain wireless devices to interact with the system.

The APIM (Accessory Protocol Interface Module) consists of 2 internal modules: the Consumer Interface Processor (CIP) and the Vehicle Interface Processor (VIP). These modules are not replaceable individually, but can be flashed independently, if required.

The CIP (Consumer Interface Processor) interfaces with all of the inputs to the APIM (Accessory Protocol Interface Module). The CIP (Consumer Interface Processor) contains an analog-to-digital-to-analog converter, as well as the Bluetooth chipset. Any consumer-available application upgrades that are available are loaded directly to the CIP (Consumer Interface Processor) through the USB (Universal Serial Bus) port.

The VIP (Vehicle Interface Processor) provides an interface between the CIP (Consumer Interface Processor) and the vehicle. The main functions of the VIP (Vehicle Interface Processor) include controlling APIM (Accessory Protocol Interface Module) power management and translating inbound and outbound signals over the HS-CAN (High Speed Controller Area Network) as well as the dedicated MS-CAN (Medium Speed Controller Area Network) between the APIM (Accessory Protocol Interface Module) and ACM (Audio Front Control Module).

The APIM (Accessory Protocol Interface Module) can receive inputs from the following audio sources:

- USB (Universal Serial Bus) port

- Audio input jack

- Bluetooth

The USB (Universal Serial Bus) port can be used for connecting a media device (such as an iPod(R)) with the device's available cable, or for directly plugging in a portable mass storage device (such as a "thumb drive"). When playing media files stored on a mass storage device, the SYNC(R) system only plays files that do not have Digital Rights Management (DRM) protection. The USB (Universal Serial Bus) port can also be used for uploading vehicle application upgrades.

The USB (Universal Serial Bus) port is powered by the APIM (Accessory Protocol Interface Module), so no external power source is needed to power a device plugged into the USB (Universal Serial Bus) port, if the device supports this feature.

The Bluetooth interface can accommodate both Bluetooth-enabled mobile phones and Bluetooth-enabled media devices. Any Bluetooth device used with the SYNC(R) system must first be paired with the system before it is operational.

Bluetooth is a secure, short-range radio frequency that allows devices to communicate wirelessly through radio waves. The operating range of a Bluetooth signal is a maximum of 9.75 m (32 ft).

Only one Bluetooth phone and one Bluetooth media device can be connected to the system at any one time. If an additional device of either type is paired with the system and made active, the APIM (Accessory Protocol Interface Module) will disconnect any active connection and establish a connection with the new device.

It is important to understand that not all mobile phones will have the same level of features when interacting with the SYNC(R) system. For a list of compatible phones, refer to the SyncMyRide website.

The SYNC(R) system can read text messages from a compatible Bluetooth-enabled phone. It can also send a text message from 1 of 15 predetermined responses.

In addition to audio information, metadata may also be sent to the APIM (Accessory Protocol Interface Module) from a device plugged into the USB (Universal Serial Bus) port. Metadata consists of such information as artist, album title, song title, and genre. The metadata is used by the APIM (Accessory Protocol Interface Module) to create indexes that can be used to sort for particular music, based on customer preference. Not all USB (Universal Serial Bus) devices can send metadata to the APIM (Accessory Protocol Interface Module) ; also, no metadata is transferred when a device is connected through the audio input jack. When a new media device is connected to the SYNC(R) system, the APIM (Accessory Protocol Interface Module) automatically indexes the information. This may take several minutes (depending on the amount of data on the device), and is considered normal operation. When a device that was previously connected to the SYNC(R) system is reconnected, the APIM (Accessory Protocol Interface Module) updates the index (rather than creating a new one), which reduces the amount of time needed to create the index.

The APIM (Accessory Protocol Interface Module) receives and transmits stereo and mono sound signals. The mono function is used to receive the microphone input. It is also used to send sound to the ACM (Audio Front Control Module) for voice prompts, the Text-To-Speech (TTS) feature, ringtones, and any audio received through a connected mobile phone. The TTS (Text-To-Speech) feature speaks information so that it does not have to be read from the display.

The APIM (Accessory Protocol Interface Module) communicates on the High Speed Controller Area Network (HS-CAN) as well as a dedicated MS-CAN (Medium Speed Controller Area Network) between it and the ACM (Audio Front Control Module). Communication with the scan tool is established through the HS-CAN (High Speed Controller Area Network).