Tesla's Full Self-Driving system misread speed limits and attempted to overtake cyclists illegally during a three-day test around Brussels, according to a Belgian road-safety group that is now urging regulators to reconsider the technology's European approvals.
The nonprofit Johanna.be tested a Tesla Model 3 over roughly 400 km in July, running FSD version 14.2.2.6 in Standard mode with the speed offset set to zero and the contextual maximum-speed setting switched off. Its 36-page report focuses on streets where pedestrians and cyclists are most exposed to risk.
The most striking finding concerns speed limits. On 29 tested road segments with a 30 km/h limit, FSD exceeded the limit on 16 of them. The car's highest speed on those segments averaged 44 km/h. In roughly 90 percent of tested segments, the system displayed an incorrect, higher speed limit to the supervising driver. In some cases, the screen briefly showed it had detected the 30 km/h sign before reverting to a displayed limit of 50 km/h.
The group also examined 12 residential home zones with a 20 km/h limit, where FSD exceeded the limit in five cases. On Belgian cycle streets, where drivers are not permitted to overtake cyclists, the system repeatedly attempted to pass them. The supervising driver had to intervene to stop several of those attempts.
The report does credit Tesla in some areas. It says FSD generally yielded to pedestrians and cyclists and behaved courteously around them. But the group argues that a car which gives its driver the wrong speed limit remains a problem, particularly on streets designed to protect vulnerable road users.
The findings carry weight because Tesla is seeking approval for FSD across the European Union. The Dutch regulator RDW approved the system for use in the Netherlands in April, and Belgium subsequently authorised it. Johanna.be has asked both authorities to revisit those approvals ahead of a possible vote on EU-wide use on 6 October.
RDW told Reuters it had received the report and would assess it in context. Tesla did not respond to the news agency's request for comment.
The test involved a single car, one software version and selected Belgian roads, so it cannot establish how often every FSD-equipped Tesla behaves this way. What it does provide is documented evidence of specific failures for regulators to examine as they weigh whether the supervised system is ready for broader European roads.
Drivers remain legally responsible for their vehicles while using FSD, but the report suggests that responsibility becomes harder to exercise when the car itself insists the limit is higher than it is. The group's intervention adds a new layer of scrutiny to a debate that will shape how autonomous driving features are approved across the continent.