Eleven motorists have filed a complaint in France, alleging their vehicles braked without warning while they were driving in incidents known as "phantom braking".
One driver says it happened when she was driving at 100km/h on a motorway with children in her car.
The plaintiffs all drive vehicles equipped with automatic emergency (AEB) systems.
AEB systems use radar and camera sensors to detect obstacles ahead and automatically apply braking to avoid a collision if a crash risk is identified.
However the drivers bringing the case say the system triggered sudden and severe braking without an obstacle in sight.
The case is now under investigation by the French market surveillance authority for vehicles and engines.
The French Ministry of Transport has also launched an investigation into whether software defects, sensor miscalibration, or system integration may be responsible for the incidents. Up until now, manufacturers have refused to acknowledge the issue.
Marie-Christine Pereira, one of the 11 who have filed a complaint, says she experienced violent and sudden braking while driving on holiday on a motorway at approximately 100km/h, with her children in the car in August 2025.
She said her Ford Focus (2020) abruptly stopped and veered towards a safety barrier.
“My car just stopped suddenly and pushed us toward the safety barrier on the motorway,” she told The Connexion.
Her 15-year-old son had to react instantly, forcefully turning the steering wheel to prevent the vehicle from entering into oncoming traffic and causing a far more serious collision.
Ms Pereira, who is registered as disabled and drives a specially adapted vehicle, says she immediately contacted Ford after the incident. According to her, the manufacturer did not acknowledge a defect.
“All the car brands say there is no problem. That’s why we are filing a complaint for endangering others,” she said.
She added that insurance classified her as responsible for the crash despite what she believes was a technical malfunction.
“We are the ones considered at fault. The issue is not recognised,” she said.
Banette Virginie, another one of the 11 plaintiffs, says she became part of the collective after discovering similar cases online, and reports a pattern of intermittent faults that eventually escalated into a full emergency braking incident.
She purchased a Dacia Sandero Stepway in 2023 and began experiencing repeated issues with cruise control and warning lights, followed by unexplained braking behaviour.
“Over several months, and even years, I didn’t realise it at first, but the car was braking unexpectedly, without any obstacle on the road,” she told The Connexion.
She then experienced a major incident while exiting a roundabout, where the vehicle activated multiple warning signals and came to a complete stop.
“The car suddenly lit up all the warning lights and braked sharply until it stopped completely,” she said. “I ended up alone on the road.”
Although no collision occurred in her case, she says the vehicle was immobilised and had to be towed after she was unable to restart it.
She says she continues to use the vehicle out of necessity, as she cannot afford a replacement.
“I have no choice. I’m leasing it, I still pay every month, so I still drive it,” she said.
She adds that she is regularly required to manually deactivate the emergency braking system before driving.
“I have to disable the emergency braking every time I use the car. That’s not normal for a vehicle I’m still paying for,” she said.
She says repeated visits to the dealership have not resolved the issue, and she is now pursuing legal action with the collective in the hope of obtaining either a solution or a replacement vehicle.
As the complaint moves forward, the group’s lawyer, Maître Anne-Sophie Charrieras, says the aim is “to identify all potential responsible parties. This could also involve certain suppliers of the devices integrated into vehicles currently in circulation,” as reported by France Info
Affected drivers have now begun organising online. A Facebook group titled ‘Collectif ‘Freinages fantômes’ automobiles’ has gathered around 3,000 members.
Different manufacturers, same issue
Christiane Balla-Montet, member of the Facebook group, described a frightening experience on the motorway near Lançon-Provence while travelling in a Skoda Kodiaq.
She said the vehicle suddenly behaved as if the ABS had activated, before swerving and coming to a complete stop across lanes, triggering multiple alarms and forcing the seatbelts to tighten automatically.
“We couldn’t do anything. The car completely stopped and the alarms went off everywhere,” she told The Connexion.
The couple eventually obtained a replacement vehicle after a seven-month dispute with the manufacturer, supported by consumer protection organisation Que Choisir.
Although no collision occurred, she said the incident left her shaken and lacking confidence in driving again.“I was very shaken. I still don’t trust the car anymore,” she said.
Lionel Cohen, a recent owner of a Cupra Formentor delivered in March 2026, also reported experiencing multiple sudden emergency braking events, including two full motorway stops.
He described a first incident at around 110km/h in the left lane, during which the vehicle activated a full emergency response.
“The SOS alarm went off, the seat belt tightened, the horn sounded, the warning lights activated, the windows closed, and the car came to a complete stop without me being able to steer,” he told The Connexion.
“I was in total panic. Cars were coming from everywhere. A truck ended up protecting me from behind,” he said.
The following week, a second identical incident occurred.
“This time the car crossed all three lanes and ended up sideways in the right lane,” he said.
He adds that, once again, no fault data or recorded event was found in the vehicle system.
“At this point the vehicle feels more dangerous than safe,” he said.
The Connexion has contacted the manufacturers regarding this issue.
