The Engine Control Unit (ECU), also known as the Engine Control Module (ECM), is an electronic device that controls the operation of an internal combustion engine. It is a microcomputer controller specifically designed for automobiles. It collects engine status information through sensors such as oxygen sensors, knock sensors, and coolant temperature sensors, and combines this information with parameters such as intake air volume and engine speed to control fuel injection quantity, ignition timing, and idle speed, forming a closed-loop control system.
The ECU consists of a microprocessor, memory, input/output interfaces, and an analog-to-digital converter. It optimizes combustion efficiency by controlling parameters such as fuel supply quantity, injection timing, and ignition engagement angle. Modern ECUs have expanded their functionality to include variable valve timing systems, turbocharger regulation, and emission control. They form a vehicle control network via a CAN bus with systems such as anti-lock braking systems and airbag systems. When the system detects a fault, it automatically generates a fault code and prompts for maintenance via the instrument panel. It possesses adaptive learning capabilities and alternative programs to maintain basic operation. ECU technology has evolved from 16-bit to 32-bit chips, supporting the China VI emission standards. In the aerospace field, engine controllers are also used in rocket control.