International Standards Organization (ISO) 9141 Communications Network

The ISO 9141 communications network is a single circuit communications network, circuit 70 (LB/WH). The ISO 9141 communications network does not permit inter-module communications. When the diagnostic tool communicates to modules on the ISO 9141 communications network, the diagnostic tool must ask for all information; the modules cannot initiate communications. The ISO 9141 communications network does not function if the circuit is shorted to ground, voltage or open. Also, if one of the modules on the ISO 9141 communications network loses power or shorts internally, communications to that module fail. The ISO 9141 communications network is used to communicate with the restraint control module (RCM) and the fire suppression module (FSM).