ISO 9141 Communications Network
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The ISO 9141 communication network does not permit intermodule communication. When the diagnostic tool communicates to modules on the ISO 9141 communication network, the diagnostic tool must ask for all information; the modules cannot initiate communications.
The ISO 9141 communication network does not function if the wire is shorted to ground or battery voltage. Also, if one of the modules on the ISO 9141 communication network loses voltage or shorts internally, communication to that module does fail.