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Electronic Control Assembly (ECA) Operation

During system operation, ECA transmits electrical reference signals to engine sensors and analyzes return signals to determine engine operating conditions. If a sensor or actuator fails, ECA initiates an alternative strategy, allowing vehicle to maintain driveability. This strategy is called Failure Mode Effects Management (FMEM).

The CHECK ENGINE light will illuminate and remain on whenever FMEM is in operation. The ECA, overriding failed component with a FMEM substitute operation value, continues to monitor failed sensor. Should signals from faulty sensor return to within operational limits, ECA will cancel FMEM control and resume control based on sensor signals.

Fig 1: EEC-IV System Component Diagram (Typical)
G90J15981Courtesy of FORD MOTOR CO.