South Korean police have referred 80 drivers to prosecutors for using unauthorized devices to switch on Tesla‘s Full Self-Driving (FSD) driver-assistance system in cars that are not approved to run it.
Tesla launched FSD (Supervised) in South Korea in November 2025, initially for US-built cars with its latest HW4 hardware. The Cybertruck, Model S and Model X were expected to be the first to get it.
The Seoul Metropolitan Police Agency’s traffic crime investigation team said on Tuesday that it had apprehended the 80 on suspicion of violating the Motor Vehicle Management Act and seized 21 of the devices.
The suspects bought FSD activation devices sold abroad, including in Europe and China, or built their own and connected them to their cars, police said. They enabled FSD without going through the software updates or certification procedures the manufacturer officially provides.
Features activated this way pose safety risks, police said, including the possibility that they fail to properly recognize driving conditions or behave differently from what the driver intends.
Two different cases
Police described two of the cases.
One suspect bought an unauthorized activation device sold in Europe and connected it to the car, using FSD without the official software update or certification, according to police.
Another one built a device using technical knowledge of vehicle electronic control systems, police said. The device was based on open-source code obtained from the developer platform GitHub.
Some suspects shared on online communities not only how to activate FSD without permission but also how to avoid leaving related records in their cars, police said. Investigators secured the posts and chat records to establish what happened.
Police said no accidents had been linked to the unauthorized activations, Kyunghyang Shinmun reported.
How the case began
The Seoul police opened the investigation after the Ministry of Land, Infrastructure and Transport requested it in April. They sought technical advice from the ministry and the Korea Transportation Safety Authority on illegal structural modifications involving FSD.
Tesla Korea had reported a vehicle cybersecurity threat stemming from a software vulnerability to the ministry on March 31, and remotely disabled the feature on cars where it had been illegally switched on, Digital Daily reported. The ministry turned to police as attempts continued, according to the report.
The ministry and Tesla Korea identified 93 vehicles suspected of illegal FSD activation, Hankyung reported. Police referred the 80 drivers without detaining them.
Violations of the law can bring up to two years in prison or a fine of up to 20 million won ($15,100), according to several Korean news reports.
“We will continue to work with relevant agencies to investigate illegal acts that threaten safety on the road,” a Seoul police official said.
FSD in Korea
Only some US-built Teslas can legally use FSD in South Korea, under a provision of the Korea-US free trade agreement that lets cars meeting US federal safety standards be sold without separate Korean certification. Cars built in China, which make up most of Tesla’s Korean fleet, do not qualify.
Of the 238,968 Teslas registered in South Korea at the end of September, 53,477, or 22.4%, could use FSD, according to data Tesla Korea provided to Democratic Party lawmaker Jang Jong-tae, Hankyung reported. China-built Model 3 and Model Y vehicles accounted for 183,407 of those that could not.
Tesla Korea applied to the ministry on October 22 for FSD conformity approval under a special provision that lets the minister allow technology regardless of current safety standards if it is judged to be an advanced new technology or necessary for safety, Hankyung reported.
A wider market
The devices seized in Seoul are part of a broader trade.
Tesla warned owners in April that anyone using such devices would bear full responsibility for any accident, and that it could refuse warranty repairs and end service for their cars, according to emails to owners reported by Chinese tech outlet Bianews. The devices typically sold for about 500 euros ($600), the report said.
Tesla described the devices as a cybersecurity threat that could open vulnerabilities for hackers, according to the same report.
In Europe, the official route has only recently opened. The Dutch vehicle authority RDW granted a European type approval for FSD Supervised valid for use in the Netherlands, it said in June.
Nearly 40,000 Teslas with the system had driven about 24 million kilometers (14.9 million miles) there since the approval with no relevant incidents, the RDW said, and it raised Tesla’s mandatory reporting from annual to monthly for the time being.
FSD’s official path in Korea
Tesla Korea then began rolling out FSD v14 Lite to US-built Model 3 and Model Y cars with older HW3 hardware on July 10, making Korea the second market after North America to receive it.
On August 21, Tesla replaced the one-time FSD purchase price of 9,043,000 won ($6,800) with a subscription of 150,000 won ($113) a month, or 75,000 won ($57) for owners of its Enhanced Autopilot package. Cars in Korea had driven 50 million kilometers (31.1 million miles) on FSD by then, Tesla Korea said.
The China-built cars that dominate Tesla’s Korean sales remain shut out. They do not qualify for the trade-agreement exemption and would have to meet Korean safety standards, which restrict lane changes outside specified conditions, Yucca Post reported.
Leading the import market
Tesla has led South Korea’s imported car market for eight straight months. It registered 12,372 vehicles in September, about 35% of all imported passenger cars, according to the Korea Automobile Importers and Distributors Association (KAIDA).
BMW was second with 6,066 and Mercedes-Benz third with 5,477.
The Model Y was the best-selling imported model with 11,421 registrations, including 8,690 of the six-seat Model Y L. That was only 208 fewer than Hyundai’s Grandeur, the best-selling domestic model.
From January through September, Tesla registered 89,148 vehicles in South Korea, 31.9% of the import market, according to KAIDA data.
Earlier this year, the brand captured 30% of South Korea’s imported car market and in April it outsold BMW and Mercedes-Benz combined.
