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Communications Network: Notes

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

Vehicle communication utilizes both medium and high speed controller area network (CAN) communications. CAN is used for many modules to communicate with each other on a common network. CAN in-vehicle networking, is a method for transferring data among distributed electronic modules via a serial data bus. Without serial networking, intermodule communication requires dedicated, point to point wiring resulting in bulky, expensive, complex, and difficult to install wiring harnesses. Applying a serial data network reduces the number of wires combining the signals on a single network. Information is sent to the individual control modules that control each function.

The vehicle has 2 module communication networks:

Both networks are connected to the data link connector (DLC). This makes diagnosis and testing of these systems easier by allowing one scan tool to be able to diagnose and control any module on both networks from one connector. The DLC can be found under the instrument panel between the steering column and the audio control module (ACM).

Fig 1: Network Topology
GF0047049Courtesy of FORD MOTOR CO.
Module Name Network Type Termination Module
Audio control module (ACM) MS-CAN No
Audio digital signal processing (DSP) module (Navigator only) MS-CAN No
Audio rear control unit (RCU) (if equipped) MS-CAN No
ABS module HS-CAN No
Driver seat module (DSM) (if equipped) MS-CAN No
Dual climate controlled seat module (DCSM) (if equipped) MS-CAN No
Heating ventilation air conditioning (HVAC) module MS-CAN No
Instrument cluster (IC) (gateway module) HS-CAN
MS-CAN
Yes
Yes
Liftgate/trunk module (LTM) (if equipped) MS-CAN No
Parking aid module (PAM) (if equipped) MS-CAN No
Power running board (PRB) module (if equipped) MS-CAN No
PCM HS-CAN Yes
Rear entertainment module (RETM) (if equipped) MS-CAN No
Restraints control module (RCM) HS-CAN No
Smart junction box (SJB) MS-CAN Yes
Satellite digital audio receiver system (SDARS) module (if equipped) MS-CAN No
Transmission control module (TCM) HS-CAN No
Vehicle dynamics module (VDM) (if equipped) HS-CAN No
4X4 control module (if equipped) HS-CAN No