The wiring rules of the electronic control system circuit can be summarized as follows:
The computer control circuit must be controlled by the ignition switch, and various sensors must input working condition signals at any time, for example: magnetic pulse or Hall sensors can generate pulse voltage signals; some sensors are made of thermistors, and the resistance changes , the output voltage also changes accordingly, which belongs to the analog voltage signal, such as water temperature, intake air temperature sensor, etc.
The actuator of the electronic control system is controlled by computer and has self-diagnosis function. Computer work is generally controlled by two modes – open loop and closed loop. For example, the open-loop control of fuel injection, after the engine computer receives the input signal, it only responds according to the preset program, and does not monitor the signal of the oxygen sensor. The open-loop operating conditions include warm-up operating conditions, deceleration operating conditions, and full-throttle valve operating conditions. The closed-loop control is that the engine computer detects the signal of the oxygen sensor, so that the fuel injection pulse width controlled by the computer can obtain the ideal air-fuel ratio to achieve the best fuel economy and low emission. Closed-loop operating conditions include idling operating conditions, cruising operating conditions, etc.