PCI Bus System
WARNING: This page is about a different car, the 1998 Dodge Intrepid and 1998 Chrysler Concorde. However, it is still accessible from the selected car via links, so may be relevant.
The Programmable Communication Interface multiplex system (PCI bus) consists of a single wire. The BCM acts as a splice to connect each module and DLC. Each module uses its local ground as bus reference. If more than one module is trying to access the PCI bus at one time, the code being sent determines which message has higher priority, and is then allowed to access bus first. Communication over the bus is essential to proper operation of vehicles on-board diagnostic systems and DRB. Problems with operation of bus or DRB must be corrected before proceeding with diagnostic testing. See VEHICLE COMMUNICATIONS .