Once the car system (especially in a closed ecosystem) undergoes a major version upgrade, its bootloader is usually locked, preventing downgrades. If this happens, there is basically no solution in an overseas environment. Therefore, we strongly warn: do not blindly insert a USB drive to upgrade while offline.

If your remitting bank requires verification of the transaction's authenticity, we will promptly provide: a commercial invoice (PI) signed and stamped by both parties, a scanned copy of the vehicle purchase contract, and our legal export enterprise registration certificate from the Ministry of Commerce in China.

Obtaining precise internal resistance at different SOC levels requires disassembling the battery pack and connecting it to a professional charge-discharge cabinet for several days of cycling tests. This is beyond the scope of non-destructive used car inspections; we only provide real-time estimated internal resistance data based on OBD port readings.