Regulators Launch Probe of GM’s Cruise Autonomous-Driving System

The agency said it received three reports of crashes involving Cruise vehicles braking hard in response to another road user approaching from behind. NHTSA learned about the incidents in which cars became immobilized through a variety of sources, it said, but the specific number of instances that occurred is unknown.

“Although the two types of incidents appear to be distinct, they each result in the Cruise vehicles becoming unexpected roadway obstacles,” NHTSA said in the filing. The investigation covers 242 vehicles from Cruise’s fleet.

Cruise said it is cooperating with NHTSA. The company said its cars have logged nearly 700,000 fully autonomous miles in what it described as a complex, urban environment, with no life-threatening injuries or fatalities.

“There’s always a balance between healthy regulatory scrutiny and the innovation we desperately need to save lives,” a Cruise spokesman said.

Cruise began offering driverless rides in June to paying customers in parts of San Francisco, after receiving its final approval from state regulators. The company on Thursday said it got clearance from the California Department of Motor Vehicles to expand the service citywide, although it still needs approval from utilities regulators.

The examination of Cruise’s operations represents the third formal probe NHTSA has opened into a developer of automated driving systems, NHTSA said. The agency has previously investigated a startup backed by the Toyota Motor Co., Pony.ai, over its handling of an earlier safety issue, a spokeswoman said.

The agency has stepped up its oversight of advanced driver-assistance features over the past year, in particular by requiring companies to submit reports of crashes. Those reports in part led NHTSA to begin its probe, the regulator said in its filing.

In recent years, Cruise and other driverless-car developers pushed back their timelines to commercialize robotaxi services, citing technical complexity and regulatory hurdles. Cruise is among a handful of companies working to expand service in U.S. cities.

Alphabet Inc.’s

Waymo division is offering fully autonomous rides in the Phoenix area.

Cruise’s commercial operations experienced setbacks within weeks of launching in San Francisco. The company had trouble with cars clustering at intersections and blocking traffic, incidents that were captured on video and posted on social media. Employees had to then manually retrieve some of the vehicles, a Cruise spokesman said.

A Cruise spokesman said safety is Cruise’s priority. If its cars encounter situations where they aren’t able to safely proceed, they pull over and turn their hazard lights on. A team is typically on site in 10 minutes, he said.

In September, Cruise said it recalled the software used in its driverless Bolts after a crash that resulted in minor injuries. Cruise said it updated the software, and the action didn’t affect or change its on-road operations.

Despite the setbacks, Cruise, which is majority owned by GM, has said it is expanding to Phoenix and Austin, Texas, by the end of this year and plans to launch in more U.S. cities next year. The company has targeted $1 billion in annual revenue by 2025 and as much as $50 billion by the end of the decade.

Cruise, meanwhile, has sought approval from California regulators to begin public testing of a shuttle called the Origin that has no steering wheel or manual controls, The Wall Street Journal has reported.

Federal regulations allow GM to deploy the Origin for testing purposes. But Cruise needs an exemption to federal motor-vehicle-standards to launch the Origin for commercial services.

GM asked NHTSA in February to grant it a temporary exemption to allow it to operate a limited number of vehicles without steering wheels or manual controls on public roadways, according to a petition submitted to regulators. The request remains pending.

Write to Ryan Felton at ryan.felton@wsj.com