Engine Control Module: Description and Operation

Engine Control Assembly:

The heart of the Electronic Engine Control (EEC-IV) system is the Electronic Control Assembly (ECA).
The ECA receives input signals from a series of sensors, makes computations based on these inputs, and sends signals to the various outputs to control many functions, including: air/fuel mixture, ignition timing, and EGR operation.
The ECA sends out a regulated, 5 volt reference voltage (VREF) to the input sensors. These sensors require a constant VREF source to provide an accurate signal. The ECA monitors the signals from these sensors and calculates the proper operating strategy for the engine operating conditions.
The ECA's calibration assembly contains the necessary programming to fine-tune the ECA's engine calibration commands to each vehicle's weight, axle ratio, and transmission application. The calibration assembly is an integral part of the ECA and is not replaceable.