Tesla blocks full self-driving access on hacked vehicles

Tesla has started blocking cars that use unapproved hardware to unlock its Full Self-Driving (FSD) feature outside licensed regions. The company says these illegal devices pose a security risk and is removing access for vehicles caught using them.

This affects owners in countries where FSD hasn’t received regulatory clearance, including Europe, China, Turkey, and South Korea. Tesla has confirmed that it can detect and disable vehicles fitted with such third-party modules.

The €500 hack

A small device selling for about €500, roughly $540, is at the center of the problem. These plug into the car’s Controller Area Network (CAN) bus, the system that handles steering, braking, and throttle signals.

By manipulating data traffic within the vehicle, the hardware tricks Tesla’s software into bypassing location locks. People use it to activate FSD (Supervised) in regions where Tesla cannot legally offer it.

Warning message to owners

Earlier this month, owners who used these devices started receiving alerts inside the Tesla app. The message said:

“Your vehicle has detected an unauthorized third-party device. As a precaution, some driver assistance functions have been disabled for safety reasons.”

Several drivers shared screenshots on X. Many found their FSD access removed permanently.

Tesla appears to be reverting those cars to standard Autopilot. Some owners are now learning that their warranties could be voided.

The company calls these modifications dangerous, saying the devices interfere with secure vehicle systems and could create safety risks.

South Korea faces legal trouble

South Korea has become one of the hardest-hit regions. U.S.-made Tesla models such as the Model S, Model X, and Cybertruck can use FSD through trade exemptions. But China-built Model Y vehicles, which dominate local sales, remain blocked by regulation.

Local authorities stepped in after reports of jailbroken hardware spread. The South Korean Ministry of Land, Infrastructure and Transport warned that installing or using these devices is a criminal act. Under the country’s Motor Vehicle Management Act, breaking these rules can lead to prison time or large fines, up to two years behind bars or 20 million won (about $14,500 USD).

Some drivers say they resorted to these devices out of frustration. In Europe, people paid thousands for FSD years ago, but regulators have delayed official approval.

That may soon change. A major step forward could come soon through Dutch vehicle regulator RDW. Approval in the Netherlands might trigger an EU-wide rollout soon after, ending years of waiting for legal use.

Tesla’s position

Tesla says its Full Self-Driving software is a supervised system that needs verified hardware for safety. The company plans a software update that will close the loophole used by the CAN bus devices.

Using illegal hardware could result in losing FSD forever, invalidating warranties, or facing criminal penalties. The company insists the security of its vehicles can’t be compromised for unauthorized access.