Electronically controlled diesel engine simulation technology diagnosis method

In the case that the fault code cannot be read and the fault is difficult to reproduce, simulation technology can be used for diagnosis. The so-called simulation technology is to reproduce the failure of the vehicle sent for repair under similar conditions and environment by way of investigation and scientific experiment, and then through simulation verification and analysis and judgment, the fault location can be accurately diagnosed and eliminated. There are three methods of analog technology diagnosis. 2.1 Environmental simulation method
Some failures of electronically controlled diesel engine control systems occur in specific environments. The main reason is that electronic components are very sensitive to factors such as specific external environments (vibration, heat, and moisture), which cause electronic control systems to fail. The advantage of the environmental simulation method is that the method of vibration, high temperature and water seepage can be used to reproduce the fault, and the location and cause of the fault can be directly and accurately judged without special equipment. The disadvantage is that the speed is relatively slow, and the technical quality and basic theory requirements of the maintenance personnel are relatively high. The diagnosis must be patient and careful, otherwise it is easy to miss the fault. Environmental simulation methods are divided into vibration method, heating method and water shower method
1 vibration method. The method of observing whether the original fault will reappear by vibrating connectors, wiring, parts and sensors in the horizontal and vertical directions is called the vibration method. This vibration method is suitable for occasional faults or when the fault does not reappear after the vehicle stops. When using the vibration method, attention should be paid to check whether there is any virtual welding, looseness, poor contact, contact ablation, wire breakage, etc. When using the vibration method, you should also pay attention not to use too much force, so as not to damage the electronic components.
2 heating method. Heating the faulty part with an electric heating blower or similar tools to make it reproduce the original fault. This heating method is suitable for the failure of electronic components due to heating. Pay attention during use, the heating temperature generally does not exceed 6080C, and the parts in the ECU must not be heated
3 water shower method. The method of reproducing the original failure by spraying water is called the water spray method. This method is suitable for situations where electronic components fail due to rain or high temperature environment or after car wash. During use, care should be taken to protect the electronic components before spraying to prevent water from corroding the electronic components. Water sprayed in front of the radiator indirectly changes temperature and humidity