Principles of Operation: Notes
WARNING: This page is about a different car, the 2003 Mercury Sable and 2003 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
The generic electronic module (GEM) receives inputs and delivers outputs to many of the electronically controlled features of the vehicle. The GEM constantly monitors the system under its control and reports a concern in the form of a diagnostic trouble code (DTC).