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.

We can purchase the hardware (diagnostic device) on your behalf. However, the original online diagnostic accounts (especially those involving anti-theft programming and module matching) have strict domestic IP location and real-name authentication restrictions, making it very difficult to log in stably from overseas for a long time, and we cannot guarantee technical support for this.

We thoroughly rule them out by checking if the cabin wiring harness is melted, if the seat belts have water stains or mold, if there is unusual rust or debris in the seat tracks and cigarette lighter, and by verifying with the insurance company for any "total loss claims." These two types of cars are an absolute sales ban for us.