U007388 - TroubleshootingU007388-故障诊断

Fault code description故障码说明

DTC故障码(DTC)	Fault code description故障码描述	Possible cause of failure可能故障原因
U007388	Vehicle CAN BusOff整车CAN BusOff	1. Short circuit in wiring harness1.线束短路
		2. Connector short circuit2.连接器短路
		3. Random hardware failure of network nodes3.网络节点随机硬件失效

Troubleshooting steps故障诊断步骤

①General inspection一般检查

1. Power state is "OFF", disconnect the negative terminal of the 12V battery.电源状态“OFF”，断开蓄电池负极。 2. Check whether the ECAN communication harness is damaged or broken.检查ECAN通讯线束是否存在损坏、断裂等现象。 3. Check the ECAN communication harness connector for loose connections or damage.检查ECAN通讯线束接插件是否存在虚接、损坏等现象。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 2.去步骤2。 No否 Repair or replace the ECAN communication harness or connector.维修或更换ECAN通讯线束或接插件。

②Check ECAN communication waveform检查ECAN通讯波形

1. Power status "OFF".电源状态“OFF”。 2. Connect the oscilloscope.连接示波器。 3. Power status "ON".电源状态“ON”。 4. Use an oscilloscope to measure the waveforms of ECAN-H and ECAN-L.用示波器测量ECAN-H和ECAN-L的波形。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 4.去步骤4。 No否 Check the ECAN communication harness; if normal, go to step 3.检查ECAN通讯线束；若正常，去步骤3。

③Check other systems on the ECAN communication harness检查ECAN通讯线束上其他系统

1. Check whether other systems on the ECAN communication harness are normal.检查ECAN通讯线束上其他系统是否正常。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 4.去步骤4。 No否 Troubleshoot faulty systems.检修故障系统。

④Replacing the integrated electric drive assembly更换集成电力驱动总成

1. Replace the integrated electric drive assembly with a new one and check whether the fault code and symptoms are eliminated.更换新的集成电力驱动总成，检查故障码及症状是否排除。 Are the test results normal?检查结果是否正常？ Yes是 Fault resolved.故障排除。 No否 Look for causes from other symptoms.从其他症状查找原因。   Caution:注意： ♦  After replacing the integrated electric drive assembly, you need to use a diagnostic tool to recalibrate the integrated electric drive assembly.更换集成电力驱动总成后，需用诊断仪对集成电力驱动总成重新标定。