Powertrain Control Module (PCM)

The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage, and all passive anti-theft system (PATS) functions.

The PCM is on the standard corporate protocol (SCP) communications network. If one of the bus wires becomes short to ground or voltage, or if some but not all termination resistors are lost, communications can continue. Check circuits 915 (PK/LB) and 914 (TN/OG) between the PCM C175 and the DLC C251. The 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 SCP communications network, damage to the DLC C251, damage to the PCM C175, or a problem in the in-line connector.

For additional PATS information, refer to ANTI-THEFT -- PASSIVE ANTI-THEFT SYSTEM (PATS) .

For additional PCM information, refer to INTRODUCTION - GASOLINE article .