Mainstream Chinese automakers rarely publish official English versions of their underlying circuit diagrams. We can provide some models' original Chinese technical documents (PDF) for B2B clients, which you will need to translate for your local mechanics using translation software.

Absolutely prohibited. Chinese customs requires a "bare car" declaration for used car exports. If undeclared goods are found inside the vehicle, it could lead to inspection and detention, or even smuggling charges. We refuse any form of concealment requests.

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.