General Information

This vehicle is equipped with a computer system capable of performing multiple engine control and body functions.

The vehicle components (windows, HVAC, locks, etc.) are directly controlled by the system's modules. Each system module communicates with the other system's modules on an interconnecting bus called the class 2 serial data line. The serial data line provides 2-way communication between all of the modules. Some electrical components are directly connected and controlled by the system module. Other systems controls the components with information the module receives over the serial data line. Any system module that completes the computer system may monitor all of the system data information.

All of the Systems on the same serial data line use a communication process similar to a telephone system. The vehicle control system is able to exchange enormous amounts of information on a single data wire.

The systems communicate by sending a digitally coded message. The message consists of specific information a system module must follow. Each system module is assigned a recognition code (address). The recognition code ensures that when a message is sent out on the serial data line, only the particular system module that has that recognition code will respond to the message.

The SBM is the power mode master. The SBM is responsible for sending a power mode message on the serial data line to the other systems. When the power mode message is sent, the other systems may respond to the message by sending their State of Health (SOH) code messages. The SOH messages indicate that the systems are able to communicate information between other systems.

The common information provides more accurate and reliable computer system control functions. The SBM uses information from the other systems in order to execute some functions.