If the instrument can display normally and correctly reflect whether the fault exists, it means that the insulation monitoring module of the high-voltage control system BMS itself is working normally;
If the meter shows that the insulation is not connected and there is a corresponding fault code, then the problem of the low-voltage control circuit should be eliminated first, including confirming whether the wiring harness and connectors of the low-voltage circuit are loose or poorly fixed, whether there is a problem with the communication CAN line, and check the terminal. Is the resistance value normal?
After eliminating the possibility of high-voltage wiring harness connection problems, check the high-voltage components one by one.
Disconnect the connectors of all high-voltage components, supply high-voltage power to the power battery pack, and measure the insulation resistance of the positive and negative poles of the battery pack to the chassis in turn. If the resistance is too low, it means that the battery pack has insulation problems and needs to be opened. Confirm the battery pack