Powertrain Control Module Software: Multiplexing
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The increased number of modules on the vehicle necessitates a more efficient method of communication. Multiplexing is a method of designating a system for sending two or more signals simultaneously over a single circuit. In an automotive application, multiplexing is used to allow two or more electronic modules to communicate simultaneously over a single media. Typically this media is a twisted pair of wires. The information or messages that can be communicated on these wires consists of commands, status or data. The advantage of using multiplexing is to reduce the weight of the vehicle by reducing the number of redundant components and electrical wiring.