Powertrain Control Module (PCM)

WARNING: This page is about a different car, the 2005 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.

The PCM is on the high speed CAN. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage, and all passive anti-theft system (PATS) functions. If one of the bus wires becomes shorted to ground or voltage, communications can continue at a reduced level. Check the high speed CAN circuits (W) and (B), between the PCM 0140-175b/275b and the DLC D-01. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the high speed CAN, damage to the DLC D-01, damage to the PCM 0140-175b/275b, or a problem in the in-line connector. Since both the PCM and the instrument cluster share network termination responsibilities, a problem in either of these modules can result in a high speed CAN failure. For additional PATS information, see ANTI-THEFT -- PASSIVE ANTI-THEFT SYSTEM (PATS) . For removal and installation information, see ELECTRONIC ENGINE CONTROL (EEC) SYSTEM .