Coming from Detroit: Networks on wheels: Multiplexed wiring in new models promises cost-effective control and accurate diagnostics, as well as fewer wires and less redundancy

Multiplexing-the simultaneous transmissions of two or more messages on a single channel-is explored as the answer to the problem of finding space in cars for the wiring needs of advanced electronic features like antilock braking, electronic steering, and electronically controlled transmissions and suspensions. Multiplexing can reduce wiring complexity and eliminate redundant parts, while simplifying diagnostics. The major types of multiplexing systems for automobile use are studied. Multiplexing network protocols proposed by the Society of Automotive Engineers (SAE), Chrysler Corp., Ford, and Bosch-Intel companies are highlighted. Associated factors for switching and cost-effectiveness are discussed.