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Engine Control Module: Description and Operation: Overview

Fig. 1 Electronic control unit:





The control unit, Fig. 1, is connected to the electronic fuel injection harness by a multi-connector and the electronic fuel injection harness is connected to the other sensors.
The purpose of the control unit is to generate a pulse signal. Upon receiving an electrical signal from each sensor, the control unit generates a pulse signal and the duration, injector open-valve time period, is controlled to provide an optimum quantity of fuel according to the engine demands.
The control unit consists of three integrated circuits formed on the printed circuit board.