故障现象一辆上海通用别克GL8车,累计行驶里程约30万km,出现起动发动机时起动机不工作,而且在接通点火开关时,仪表盘上的挡位指示灯不指示。故障诊断经过了解得知,该车因发动机工作时出现异响而对发动机进行了检查,发现机油泵和气门摇臂有问题,就将发动机拆下,更换了机油泵和气门摇臂。发动机在下面修好后装车,试车中发现了上述故障。当时就用故障检测仪检测,发现故障检测仪无法与发动机系统进行通讯。检查诊 Symptom A Shanghai GM Buick GL8 car, the cumulative mileage of about 300,000 km, the starter does not start when the engine does not work, but also in the ignition switch, the instrument panel gear indicator does not indicate. Troubleshooting Knowing that the car was abnormal noise due to engine work and the engine was checked and found that the oil pump and valve rocker arm problem, the engine removed, replaced the oil pump and valve rocker arm. After the engine is installed in the following loading, the test found the above failure. At that time, the fault detector was used to detect and found that the fault detector could not communicate with the engine system. Check the doctor