Powertrain Control Module Software: Multiplexing
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The increased number of modules on a vehicle dictates a more efficient method of communication. Multiplexing is a process of communicating several messages over the same signal path. This process allows multiple modules to communicate with each other and to the PCM using Standard Corporate Protocol (SCP) BUS(+) and BUS(-) circuits, which determine the priority in which the signals are sent. For additional information, see STANDARD CORPORATE PROTOCOL . Multiplexing reduces the weight of the vehicle by reducing electrical wiring.