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.

Most new car manufacturers' e-SIMs are directly soldered onto the T-Box motherboard (surface-mounted) and cannot be removed and replaced like a phone. Unauthorized desoldering of the motherboard may cause complete communication failure in the vehicle, and we strictly prohibit this operation.

If the car has been maintained at an authorized dealer, we can extract the desensitized official maintenance history (including entry time, mileage, and maintenance items) through a paid third-party data provider and provide it to you. If some year records are missing, we will honestly inform you that the "records are incomplete."