According to Tom's Hardware, the devices connect to the car's CAN bus. The bypass works because Tesla installs the same computer in every car, including where the feature is not approved. Some suspects bought ready-made units from Europe and China, and one, an IT worker, built his own from information found on GitHub. The suspects also traded tips on hiding activation records.
Prosecutors are relying on the Motor Vehicle Management Act, which bans unauthorized software changes that could affect safety. The transport ministry flagged suspicious activations to police in April. Tesla has offered FSD (Supervised) in South Korea since late 2025, but only on US-built Model S, Model X and Cybertruck units. The Model 3 and Model Y come from Giga Shanghai and have not yet passed certification.
Tesla itself began remotely detecting unlock devices in April and disabling FSD on affected cars, and warned that such modifications could void the warranty.