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 use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).

Under FOB or CIF terms, all risks before crossing the ship's rail are borne by the seller (us). For minor scratches, we will provide a price discount based on the damage assessment; for serious damage, we will immediately terminate the vehicle delivery, refund the full amount, or replace it with a vehicle of equivalent configuration.