U007688 - TroubleshootingU007688-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
U007688	ECAN/CANFD2 bus closedECAN/CANFD2总线关闭	1.CAN line or network failure1.CAN线或网络故障

Troubleshooting steps故障诊断步骤

①Power on check上电检查

1. Power on the vehicle again and check whether the fault code and symptoms are eliminated.车辆重新上电，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 Go to step 2.去步骤2。

②Check your surroundings检查周围环境

1. Check the surrounding environment for sources of magnetic fields.检查周围环境是否存在磁场源。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 3.去步骤3。 No否 Drive away from the current situation.驶离当前所处环境。

③Check wiring harness and connectors检查线束及接插件

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 4.去步骤4。 No否 Repair or replace faulty wiring harness or connector.维修或更换故障线束或接插件。

④Check 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 5.去步骤5。 No否 Check the ECAN communication harness; if normal, go to step 5.检查ECAN通讯线束；若正常，去步骤5。

⑤Check other related systems on the ECAN communication bus检查ECAN通讯总线上其他相关系统

1. Check whether other related systems on the ECAN bus are normal.检查ECAN总线上其他相关系统是否正常。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 6.去步骤6。 No否 Repair related faulty systems.维修相关故障系统。

⑥Replace the battery pack assembly更换电池组箱总成

1. Replace the battery pack assembly with a new one and check whether the fault code and symptoms are eliminated.更换新的电池组箱总成，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 battery pack assembly, you need to use a diagnostic tool to recalibrate the battery pack assembly.更换电池组箱总成后，需用诊断仪对电池组箱总成重新标定。