Description & Operation
WARNING:
Deactivate air bag system before performing any service operation. See AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy.
Vehicle Electronic Control Units (ECUs) are connected to each other by communication buses through which various signals are transmitted. Communication buses are diagnosed by a gateway (body) ECU. When body ECU detects a communication error between ECUs, or a short to voltage or ground of a communication bus, a DTC is output and stored. The multiplex control system consists of a gateway (body) Electronic Control Unit (ECU) connected to 2 communication buses. The multiplex communication system consists of 3 Body Electrical Area Networks (BEANs) which include door system communication bus, instrument panel system communication bus and light system communication bus.