U041781 - TroubleshootingU041781-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
U041781	Invalid data received from EPB (0x397)从EPB收到无效数据(0x397)	1. Bus interference1.总线干扰
		2.EPB damaged2.EPB损坏
		3. EPB CAN communication abnormality3.EPB的CAN通信异常

Troubleshooting steps故障诊断步骤

①General inspection一般检查

Check whether the PCAN communication harness is damaged or broken.检查PCAN通讯线束是否存在损坏、断裂等现象。

Check the PCAN wiring harness connector for loose connections or damage.检查PCAN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 faulty communication harness.维修或更换故障通讯线束。

②Power on check上电检查

Repower the vehicle, use the diagnostic tool to read and clear the fault codes, and check whether the fault codes and symptoms are eliminated.车辆重新上电，使用诊断仪读取并清除故障码，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 3.去步骤3。

③Check for electromagnetic interference检查电磁干扰

Check for sources of magnetic fields around the vehicle.检查车辆周围是否存在磁场源。

Are the test results normal?检查结果是否正常？

Yes是

Go to step 4.去步骤4。

No否

Move the vehicle away from its current environment.使车辆驶离当前环境。

④Check EPB fault code检查EPB故障码

Use the diagnostic tool to read the EPB fault code and check whether there is a fault in the electronic parking control unit.使用诊断仪读取EPB故障码，检查电子驻车控制单元是否存在故障。

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

Troubleshoot the electronic parking control unit according to the fault code.根据故障码排除电子驻车控制单元故障。

⑤Replace airbag electronic control unit更换安全气囊电控单元

Replace the airbag electronic control unit with a new one and check whether the fault code and symptoms are eliminated.更换新的安全气囊电控单元，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 airbag electronic control unit, you need to use a diagnostic tool to recalibrate the airbag electronic control unit.更换安全气囊电控单元后，需用诊断仪对安全气囊电控单元重新标定。