Network Message Chart

WARNING: This page is about a different car, the 2016 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: A missing network message is indicated by a U-code DTC. When a missing message DTC (U-code) sets, it is important to look for symptoms present in the audio system and throughout the vehicle, and to review the complete message list to determine which other modules rely on the same message. Refer to CAN Module Communication Message Chart in Module Communications Network . When the other modules have been identified, run the self-test for those modules. If the same message is missing from those modules, the identical, or similar lost communication DTCs may be set in those modules. Confirmation of missing messages common to multiple modules can indicate that the originating module is the source of the concern, or that the communication network may be at fault.

It is very important to understand the following:

Where the input originates
All of the information necessary for a feature to operate
Which module(s) receive(s) the input or command message
Which module controls the output of the feature
If the module that receives the input controls the output of the feature, or whether it outputs a message over the CAN to another module.

Module Network Input Messages - ACM

Broadcast Message	Originating Module	Message Purpose
Audio settings	IPC	Used to confirm the audio system data shown in the IPC
Beltminder warning status	RCM	Used to mute speaker output so the Belt-Minder ® tone can be more easily heard. The speaker output is muted until the safety belt(s) are buckled. This message only applies to vehicles with a MyKey ® that is enabled and in use.
Car mode	BCM	Used to disable certain audio system features when the vehicle is in transport or factory mode.
Day/night status	BCM	Used to adjust the AM radio reception sensitivity.
FCIM set volume	FCIM	Used to set the audio system volume from the FCIM.
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN and START) required to support the audio system operating modes and fault reporting.
MyKey volume limit	IPC	Used to limit the maximum audio system volume when a MyKey ® restricted key is in use.
Steering wheel switch multimedia commands	SCCM	Used to control the audio system from the RH steering wheel switches.
Steering wheel switch volume command	SCCM	Used to set the audio system volume from the RH steering wheel switches.
Vehicle speed	PCM	Used to support the speed compensated volume feature.
Rear audio commands	Audio RCU module	Used to set the audio system volume, select media and utilize the seek +/- function from the rear seat audio controls.

Module Network Input Messages - Audio RCU Module

Broadcast Message	Originating Module	Message Purpose
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN and START) required to support the audio system operating modes and fault reporting.
ACM information and status	ACM	Used to display the current audio system media selection at the rear seat audio controls.

Module Network Input Messages - APIM

Broadcast Message	Originating Module	Message Purpose
Airbag deployment status	RCM	Used to monitor airbag deployment status for 911 assist.
Audio source	ACM	Used to monitor the current audio system media source selection.
Car mode	BCM	Used to disable certain audio system features when the vehicle is in transport or factory mode.
FCIM button press data	FCIM	Used to control the APIM media sources and interact with connected devices from the FCIM.
Ignition key type	BCM	Used to determine if a MyKey ® is enabled and in use.
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN, and START) required for APIM operating modes and fault reporting.
Steering wheel switch multimedia commands	SCCM	Used to control the audio system from the RH steering wheel switches.

Module Network Input Messages - FCDIM

Broadcast Message	Originating Module	Message Purpose
ACM signals	ACM	Used to display the ACM radio functions such as seek, tune and AM/FM stations on the FCDIM.
Audio source	ACM	Used to display the selected audio source on the FCDIM.
Car mode	BCM	Used to disable certain audio system features when the vehicle is in transport or factory mode.
CD status	ACM	Used to display CD information on the FCDIM
CD load/eject	ACM	Used to display the loaded or ejected CD status on the FCDIM.
Gear lever position	BCM	Used to verify the gear selector position for bezel diagnostics.
GPS compass direction	GPSM	Used to display the current vehicle compass heading on the FCDIM
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN, and START) required for FCDIM operating modes and fault reporting.
Illumination dimming level	IPC	Used to control the backlight intensity of the FCDIM based on the dimmer switch input.
Language selection	IPC	Used to display information on the FCDIM in the selected language.
Voice recognition status	APIM	Used to display the voice recognition status in the FCDIM.

Module Network Input Messages - FCIM

Broadcast Message	Originating Module	Message Purpose
Climate control settings	HVAC module	Used to indicate the current climate control settings using the FCIM climate control button LEDs.
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN, and START) required for FCIM operating modes and fault reporting.
Car mode	BCM	Used to disable certain audio system features when the vehicle is in transport or factory mode.

Module Network Input Messages - GPSM

Broadcast Message	Originating Module	Message Purpose
Ignition status	BCM	Used to indicate the ignition state (OFF, ACCESSORY, RUN, and START) required for GPSM operating modes and fault reporting.
Selector lever (PRNDL) status	BCM	Used to verify the gear lever position for vehicle direction data.