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Information Bus: Description and Operation

COMMUNICATIONS NETWORK

Anti-Lock Brake System/Traction Control (ABS/TC) Module Or Stability Assist Module (if equipped)
The ABS/TC module or stability assist module (if equipped) are on the standard corporate protocol (SCP) communications network. The ABS/TC module or stability assist module controls the brake pressure to the 4 wheels to keep the vehicle under control while braking.

Audio Control Module (ACM)
The ACM is connected to the SCP communications network and also to the audio control protocol (ACP) communications network. The ACM communicates with the compact disc player/changer using the ACP. The ACM uses the SCP communications network for diagnostics.

Driver Door Module (DDM)
The DDM is connected to the SCP communications network. The DDM accepts the user memory set and recall buttons. The DDM then sends the memory set and recall commands to the other modules over the SCP communications network. The DDM also controls the driver mirror (memory positions are stored there and manual functions are controlled there). The driver seat module (DSM) controls the driver seat. The front electronic module (FEM) control the passenger mirror and adjustable pedals positions. The instrument cluster controls the steering column positions.

Driver Climate Control Seat Module
The driver climate control seat module is on the universal asynchronous receiver-transmitter (UART)-based protocol (UBP) communications network. The driver climate control seat module and duel automatic temperature control (DATC) module control the heating and cooling elements in the seat for passenger comfort.

DSM
The DSM is on the SCP communications network. The DSM controls the positioning and programming of the driver seat.

DATC Module
The DATC module is on the SCP communications network and the UBP communications network. The DATC module uses the SCP communications network to communicate with the diagnostic tool and other modules. The UBP communications network is used by the DATC module for communication with the driver climate control seat module. The DATC module controls automatic climate functions that maintain the vehicle interior temperature at a constant setting.

Electric Parking Brake Module
The electric parking brake module is connected to the SCP communications network. The module controls the solenoid which applies and releases the parking brake.

FEM/Rear Electronic Module (REM)
The FEM and REM are connected to the SCP communications network. The FEM and the REM control both interior and exterior lighting and perimeter anti-theft functions.

Instrument Cluster
The instrument cluster is on the SCP communications network. It is an analog face cluster with a digital odometer. The instrument cluster displays a variety of information.

Passenger Climate Control Seat Module
The passenger climate control seat module is on the UBP communications network. The passenger climate control seat module and DATC module control the heating and cooling elements in the seat for passenger comfort.

Parking Aid Module
The parking aid module is connected to the UBP communications network. The module controls sensors in the rear bumper that detect close objects when the transmission is in REVERSE.

Powertrain Control Module (PCM)
The PCM is on the controller area network (CAN) and the SCP communications network. The PCM uses the CAN to communicate with the diagnostic tool and utilizes the SCP communications network to communicate with other modules. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage. Refer to Computers and Control Systems for diagnosis and testing of the PCM.

Restraint Control Module (RCM)
The RCM is on the international standards organization (ISO) 9141 communications network. The RCM controls the deployment of the air bags based on sensor input.

Navigation System Module
The navigation system module is on the SCP communications network. The navigation system module communicates with the audio unit using a dedicated CAN. The vehicle navigation system provides a feature that will guide the user to any entered destination. The system uses the global positioning sensor (GPS), vehicle speed, and other sensor information to accurately establish the vehicle position. The navigation system module compares this position to the digital video disc (DVD) vector map. The system then provides the maneuvers required during the journey in order to arrive at the destination entered.