Powertrain Control Module (PCM)
WARNING: This page is about a different car, the 2006 Mercury Montego, 2006 Ford Freestyle, and 2006 Ford Five Hundred. However, it is still accessible from the selected car via links, so may be relevant.
The PCM uses the high speed CAN for communication with the diagnostic tool. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage. For additional information, refer to INTRODUCTION - GASOLINE article for diagnosis and testing of the PCM.