Description & Operation
WARNING: This page is about a different car, the 1999 Mazda B4000, 1999 Mazda B3000, and 1999 Mazda B2500. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Two-wheel drive vehicles without power windows and/or power door locks are equipped with a Central Timer Module (CTM). All other vehicles are equipped with a Generic Electronic Module (GEM).
Vehicle has 2 module communications networks. The Powertrain Control Module (PCM) is connected to the Standard Corporate Protocol (SCP) multiplex communications network through a pair of twisted wires or BUS. The BUS consists of a positive (+) circuit and negative (-) circuit (circuit No. 914 and 915 respectively).
The air bag diagnostic monitor and all other optional modules, the Generic Electronic Module (GEM), Remote Anti-Theft Personality (RAP) module and 4-Wheel Anti-Lock Brake System (4WABS) module, are connected to the International Standards Organization (ISO) 9141 diagnostic communications network through a single wire (circuit No. 70). Both networks are connected to the Data Link Connector (DLC). See Fig 1.