NHTSA Investigates Comma.ai Driver-Assistance System After 5 Crashes and 3 Deaths

September 28, 2026

comma.ai NHTSA investigation — NHTSA has opened Preliminary Evaluation PE26007 into comma.ai’s aftermarket driver-assistance products following five crashes involving stopped or slow-moving vehicles. The investigation covers an estimated 30,000 comma three, comma 3X and comma four devices and openpilot software, but regulators have not yet determined that a safety defect exists. Frame Stock Footage/Shutterstock

Federal safety regulators have opened an investigation into aftermarket driver-assistance technology from comma.ai following five crashes involving vehicles that struck stopped or slow-moving vehicles in their travel lanes.

The National Highway Traffic Safety Administration opened Preliminary Evaluation PE26007 on September 21, 2026. The investigation covers an estimated 30,000 comma three, comma 3X and comma four devices, along with the company’s openpilot software.

According to NHTSA’s opening investigation information, regulators identified five crashes involving vehicles equipped with comma devices that struck stopped or slow-moving vehicles in the same lane. Two of the crashes resulted in a total of three reported deaths, while four of the five crashes resulted in 11 nonfatal injuries, including serious injuries.

NHTSA’s Office of Defects Investigation says preliminary information suggests the comma system may not have adequately detected or responded to the vehicles in the travel lane. Investigators will seek additional information to determine the status of the comma system during each incident and evaluate both system performance and safeguards intended to help ensure safe operation.

The investigation does not mean NHTSA has concluded that comma.ai’s products contain a defect or that the technology caused the crashes. A Preliminary Evaluation is an early stage in NHTSA’s investigative process used to determine whether additional action is warranted.

Comma.ai sells aftermarket hardware that allows owners of compatible vehicles to run its open-source openpilot driver-assistance software. The company describes openpilot as an advanced driver-assistance system capable of adaptive cruise control and automated lane centering, including steering, acceleration and braking for other vehicles within the lane.

The company also makes clear that the technology does not eliminate the driver’s responsibilities. Comma.ai says drivers must remain alert, pay attention and be prepared to take manual control immediately.

The company’s current website says more than 30,000 vehicles are using comma technology, with more than 400 million miles driven. Comma.ai says openpilot works with hundreds of vehicle models, although compatibility and available functions differ by make, model and model year.

Unlike driver-assistance technology installed by an automaker at the factory, comma’s devices can be purchased separately and installed in compatible vehicles. The company says its hardware connects to a vehicle’s existing systems without requiring permanent vehicle modifications.

NHTSA’s investigation will also consider incidents involving modified versions, or “forks,” of openpilot when relevant, including components those versions share with comma’s software.

For consumers already using a comma device, the investigation does not currently amount to a recall or an instruction from NHTSA to stop using the product. Owners should nevertheless understand the limitations of the technology and follow the manufacturer’s requirement that the driver remain attentive and ready to take control.

Consumers who believe they’ve experienced a safety problem involving a comma device or other driver-assistance system can report a safety problem to NHTSA. Those complaints can provide federal investigators with additional information about possible defect trends.

NHTSA’s investigation remains open, and there is no guarantee it will result in a recall. Regulators could close the Preliminary Evaluation if the evidence doesn’t support additional action or escalate the matter if further investigation is warranted.

Consumers using comma.ai hardware should watch PE26007 for updates while continuing to treat openpilot as a driver-assistance system rather than autonomous driving technology. Even when automated steering, acceleration or braking is active, comma.ai says the driver must remain capable of immediately retaking manual control.