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The mileage is about 38 thousand km, equipped with Chery's Fengyun 7160ET car with multi point EFI engine. The engine could not restart after the car was flameout, and replaced the crankshaft position sensor at the roadside repair shop, but there was no high pressure fire after the replacement. Fault diagnosis: after receiving the car, the fault code is read by the OTC integrated analyzer in the United States. The ECU memory has two fault codes, "the crankshaft position sensor circuit breaker" and "the intake temperature / pressure sensor to the positive pole short circuit and the circuit breaker". Once the fault code is removed, it will read again and display the same fault information. A multimeter is used to detect the line between the crankshaft position sensor and the intake temperature / pressure sensor and the engine ECU. There is no short circuit or open circuit. The crankshaft position sensor and inlet temperature / pressure sensor of the same type car are installed on the defective vehicle, and the engine is still unable to start. There seems to be no problem with sensors and lines. Next step is to detect engine ECU. Generally speaking, ECU will fail if water immersion, heat, strong magnetic field interference or abnormal high voltage, but customers say the ECU of the car is new, neither soaked nor heated, the high pressure line is a new line that has been changed in the previous period, and there is no strong magnetic field around it. Now there is only one point, that is, the abnormal high voltage causes ECU to burn out. The high voltage comes from the generator, so the magnetic field line and armature line on the generator are removed, the new ECU is installed, the engine is started, the engine can start normally, but there is no idle speed. At the moment, the voltage of the magnetic field junction column is given to the generator, and the armature voltage of the generator is as high as 22.5V. It seems that the performance of the magnetic field or coil is unstable and the output voltage is too high. So the high voltage is bound to damage the ECU or other electronic components. The fault code is read by the OTC comprehensive Chinese engine integrated analyzer. There is still a fault code of "intake temperature / pressure sensor on the positive pole short circuit and open circuit". Troubleshooting: after the intake temperature / pressure sensor and generator are replaced, the engine operates normally, and the trouble is completely eliminated.