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Engine Control Module: Description and Operation




The center of the EEC IV system is a microprocessor called the Electronic Control Assembly (ECA). The ECA, receives data from a number of sensors and other electronic components (switches, relays, etc.). The ECA contains a specific calibration for optimizing emissions, fuel economy, and driveability. Based on information received and programmed into its memory, the ECA generates output signals to control various relays, solenoids, and other actuators.


The ECA in the EEC IV system is a microprocessor like the one in the other EEC systems. One significant difference is that this ECA has the calibration module located inside the ECA assembly, unlike the EEC III system.









The ECA is found in different locations, depending on the model.