Communications Network - System Operation and Component Description

Gateway Module

The GWM is mounted under the driver side instrument panel. The DLC connector is fitted to the GWM. The GWM acts as a central gateway to translate messages across all 4 vehicle controller area networks (CANs), and vice versa. The GWM is the only module on this vehicle with this ability. The GWM also serves as a termination module for each of the networks to which it is connected.

The 2 module communication networks connected to the DLC are HS-CAN1 and HS-CAN2. These 2 networks communicate directly with the diagnostic scan tool. The other 2 communication networks, HS-CAN3 and MS-CAN, communicate on the network, but do not communicate directly with the diagnostic scan tool. The GWM translates the messages from these 2 networks to the HS-CAN2, which transfers the signals to the diagnostic scan tool.

High Speed Controller Area Network 1 and 2 (HS-CAN1, HS-CAN2)

The HS-CAN1 and HS-CAN2 operate at a maximum data transfer speed of 500 Kbps and are designed for real time powertrain and driver feature information transfer and control. Modules on the HS-CAN1 and HS-CAN2 communicate using bussed messages. The HS-CAN uses an unshielded twisted pair cable, data bus (+) and data bus (-) circuits. In addition to scan tool communication, the HS-CAN allows sharing of information between all modules on each HS-CAN.

With the addition of more modules, network traffic has increased. This has created the need for an additional HS-CAN to manage the increased bus data carried on each network.

The GWM is used as a gateway for the messages to transfer between the scan tool and the modules on the HS-CAN1 and the modules on the HS-CAN2.

The scan tool communicates with the vehicle communication networks directly through the HS-CAN1 and HS-CAN2.

High Speed Controller Area Network 3 (HS-CAN3)

The HS-CAN3, or the Infotainment Controller Area Network (I-CAN), operates at a maximum data transfer speed of 500 Kbps and is designed for real time audio, multimedia and driver information transfer and control. Modules on the HS-CAN3 communicate using bussed messages. HS-CAN3 uses an unshielded twisted pair cable, data bus (+) and data bus (-) circuits, and allows sharing of information between all modules on the network.

The GWM is used as a gateway for the messages to transfer between the scan tool and the modules on the HS-CAN3.

The GWM translates the diagnostic messages from the HS-CAN2 to the HS-CAN3 and vice versa, allowing communication beween the modules on the HS-CAN3 and the scan tool.

Medium Speed Controller Area Network (MS-CAN)

The MS-CAN operates at a maximum data transfer speed of 125 Kbps and is designed for general information transfer. Modules on the MS-CAN communicate using bussed messages. The MS-CAN uses an unshielded