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Engine Control Module: Description and Operation

ECM

Component Description




The ECM consists of a microcomputer and connectors for signal input and output and for power supply. The ECM controls the engine.

ECM POWER SUPPLY

Component Description




Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.