Malfunction Indicator Light (Mil)
WARNING: This page is about a different car, the 1995 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
The MIL will illuminate when ignition switch is turned to the ON position (bulb check), or when systems related to the EEC-IV system malfunction during normal engine operation. For additional information, see appropriate article in the ENGINE PERFORMANCE section: