Description And Operation: Operation
The Security Gateway Module (SGW) is the Controller Area Network (CAN) gateway between the radio, telematics modules, Data Link Connector (DLC) and the other vehicle CAN modules. An SGW failure could prevent the radio from powering up, telematics module from communicating or a scan tool from communicating with the vehicle. For additional information on the SGW. Refer to MODULE, SECURITY GATEWAY (SGW), DESCRIPTION AND OPERATION .
The radio ETM receives a direct battery power supply from the Body Control Module (BCM).
The radio display receives a power supply from the radio ETM.
The radio ETM is connected to the BCM and the other system nodes, in particular to the instrument panel, for indicating faults in the sound system using the Controller Area Network (CAN).
The BCM receives direct battery power and is protected by a maxi fuse on the Battery Distribution Unit (BDU).
The BCM receives an ignition-operated power supply from the Radio Frequency Hub (RFH) Module.
The radio controls on the steering wheel are connected to the BCM via the clockspring through Local Interface Network (LIN) bus 2.
The control knob on the center console connects to the Entertainment Multimedia Control Module (EMCM) which in turn sends the control signals to the radio display.
EMCM is powered from and protected by a fuse in the Rear Power Distribution Center (PDC).
The EMCM is connected to the BCM and other system nodes via the CAN.
The radio speaker signals come directly from the radio if the audio system has no amplifier or from the amplifier if the audio system is equipped with an amplifier. The amplifier, if equipped, receives specific speaker signals from the radio.
The AM/FM/FM2/SDARS antenna is connected to the radio through dedicated coaxial cables.
The AUX port is powered from the Rear PDC and protected by a fuse.
The Security Gateway Module (SGW) is in the audio and telematics systems to provide security against certain types of attacks and threats from the scan tool, telematics and entertainment buses, which can put the rest of the vehicle's buses at risk of intrusion. The SGW lies electrically between the vehicle on one side, and the Data Link Connector (DLC), telematics and entertainment systems on the other side. The main function is to gate messages from one bus to another. The SGW monitors the B(+) Feed, switched ignition feed, CAN circuits, software and hardware for any concerns.