Powertrain Control Module (PCM)
WARNING: This page is about a different car, the 2005 Mercury Sable and 2005 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
The powertrain control module (PCM) controls operation of the transaxle. Many input sensors provide information to the powertrain control module. The PCM then controls the actuators which affect transaxle operation.