Component Description
Audio Front Control Module (ACM)
The ACM can be operated with the ignition in RUN, ACC, or OFF.
The ACM receives radio waves containing audio from the antenna coaxial cables and converts them into fluctuating AC voltage. The ACM receives stereo and mono audio signals from the APIM in the form of fluctuating AC voltage. The ACM processes all inputs, and sends stereo or mono analog audio signals to the audio system speakers as fluctuating AC voltage.
The ACM receives radio waves containing satellite radio data and HD Radio® data through the antenna coaxial cables. The data is sent to be displayed on the centerstack infotainment display.
The ACM requires PMI when it is replaced.
Accessory Protocol Interface Module (APIM)
The APIM can be operated with the ignition in RUN, ACC, or OFF.
The APIM receives stereo and mono inputs. Stereo inputs include audio from the USB port(s), connected Bluetooth-enabled media device, and the outside device during a phone call. Mono input includes signals from the SYNC® microphone.
The APIM sends stereo and mono audio signals to the ACM as fluctuating AC voltage. Stereo outputs include audio from the USB ports, connected Bluetooth-enabled media device, ringback tone, outside device during a phone call, voice or tone prompts initiated from the voice steering wheel switch, and instructions or information spoken by the SYNC® system when initiated from the voice steering wheel switch. Mono outputs include audio from the TTS (text-to-speech) feature, incoming call ringtone, instructions or information spoken by the SYNC® system when initiated from the FDIM, and navigation route guidance voice or tone prompts (if equipped with navigation).
The APIM receives data from the ACM through the Sirius Data Link (SDL) circuits. This data is processed and sent to be displayed on the FDIM.
The TTS feature allows the customer to hear information through the audio system speakers so it does not have to be read from the centerstack infotainment display and/or device while driving. Examples include incoming text message sender information, text messages, and metadata from audio being played via USB or Bluetooth.
The APIM consists of 2 internal modules: the CIP and the VIP. The modules are not replaceable individually, but can be programmed independently if required.
The CIP provides an interface for all customer inputs to be read by the APIM. It contains an analog-to-digital-to-analog converter, as well as the Bluetooth and Wi-Fi chipset.
The VIP provides an interface between the CIP and the vehicle. Its main functions are controlling the APIM power management and translating inbound and outbound CAN signals.
The APIM provides the FDIM with power and ground through the LVDS (Low Voltage Differential Signaling) cable.
The APIM receives GPS data through the GPS coaxial cable. The data is used for the navigation system (if equipped) and SIRIUS Travel Link date/time-dependent features such as sports schedules and scores, movie times, and the 5-day weather forecast. The APIM also uses this data to identify the vehicle's location in the event of a collision and to display the compass heading on the FDIM.
The APIM requires programming when it is replaced.
Antenna
The AM/FM radio uses the on-glass AM and FM antennas to receive analog radio waves. The radio waves are sent through the antenna module and AM/FM antenna coaxial cable to the ACM, where they are further amplified.
To compensate for AM signal strength loss as the radio waves are transmitted from the antenna to the ACM, battery voltage is applied to the antenna module to boost the AM radio signal. This allows the AM radio waves entering the ACM to be approximately the same strength as they were before amplification at the antenna.
If equipped, the HD Radio® uses the on-glass AM and FM antennas to receive radio waves containing digital audio and data. The radio waves are sent through the AM/FM antenna coaxial cable to the HD Radio® receiver built into the ACM. The radio waves containing digital audio are amplified to improve reception.
The satellite radio uses the roof-mounted satellite radio/GPS antenna to receive signals containing digital audio and data. These signals are sent through the satellite radio/GPS coaxial cable, satellite radio/GPS splitter, and satellite radio antenna coaxial cable to the satellite radio receiver built into the ACM.
FCIM
The FCIM audio functions can be operated with the ignition in RUN, ACC, or OFF.
The FCIM audio system buttons provide one of the methods in which the customer interacts with the infotainment system.
The FCIM is separate from the ACM.
The FCIM requires PMI when it is replaced.
FDIM
The FDIM can be operated with the ignition in RUN, ACC, or OFF.
The capacitive touch FDIM provides one of the methods in which the customer interacts with the infotainment system. For more information, refer to "Using the Touchscreen" in the Owner's Literature.
The FDIM is attached to the APIM.
As the FDIM does not communicate on the CAN, the APIM acts as the proxy for all FDIM inputs and outputs requiring CAN communication. Communication between the FDIM (including FDIM customer inputs) and APIM is accomplished via the Low Voltage Differential Signaling (LVDS) cable. The FDIM power and ground are provided by the APIM through the Low Voltage Differential Signaling (LVDS) cable.
Low Voltage Differential Signaling (LVDS) Cable
The Low Voltage Differential Signaling (LVDS) cable contains 4 shielded circuits that provide power and ground to the FDIM from the APIM, and is also the means by which data is transmitted from the APIM to the FDIM and from the FDIM to the APIM.
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.
Steering Wheel Switches
The RH steering wheel switches contain a series of resistors. Each steering wheel switch function corresponds with a specific resistance value within the switch.
SYNC® Microphone
The SYNC® microphone is powered by the APIM.
The SYNC® microphone receives SYNC® system voice commands and outgoing audio during a phone call. The monitored sounds are converted into analog signals by the microphone and sent to the APIM as fluctuating AC voltage.
USB Hub
The USB hub contains two USB ports. The USB ports allow audio from portable media devices to play through the audio system speakers.
The USB hub is powered by dedicated circuits carrying battery voltage and ground from the APIM. The APIM outputs approximately 5V on the USB cable to power the USB cable data communication circuits.
The USB ports can be used to power and/or charge a device if the device supports this feature and does not have a power consumption requirement of more than approximately 5V and 2.5A (about 13 watts).
Data is sent from the two USB ports to the APIM through a single USB cable.