P164921 - TroubleshootingP164921-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
P164921	Low insulation resistance alarm (relay closed)绝缘阻值低告警（继电器闭合）	1. Abnormal insulation of the high-voltage part of the vehicle1.整车高压部分绝缘异常

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 external high-voltage electrical appliances检查外部高压电器

1. Check whether the external high-voltage electrical appliance is faulty.检查外部高压电器是否存在故障。 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 Replace faulty high-voltage components.更换故障高压部件。

③Check external high voltage circuit检查外部高压回路

1. Check whether there is a fault in the external high-voltage circuit.检查外部高压回路是否存在故障。 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 Replace the faulty high-voltage circuit harness.更换故障高压回路线束。

④Replace 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。