1, ECU input voltage: gasoline engine 12V, diesel engine 24V, output 5v; The working voltage of most sensors is 5V, and the working voltage of a few sensors with high power consumption (such as heating elements of oxygen sensors) is 12V or 24V. As long as the ignition switch is in the on position, the input voltage of the sensor will not change whether the engine is working or not.

2、ECU

(1) ECU (electronic control unit) Electronic control unit, also known as "trip computer" and "vehicle computer". In terms of use, it is a special microcomputer controller for automobiles.

(2) Function: Like ordinary computers, it consists of microprocessor (CPU), memory (ROM, RAM), input/output interface (I/O), analog-to-digital converter (A/D) and large-scale integrated circuits such as shaping and driving. To describe it in a simple sentence is "ECU is the brain of a car".