US ramps up probe of Teslas with Autopilot

DETROIT — Teslas with partially automated driving systems are a step closer to being recalled after the U.S. elevated its investigation into a series of collisions with parked emergency vehicles or trucks with warning signs.

The National Highway Traffic Safety Administration said Thursday that it is upgrading the probe to an engineering analysis, another sign of increased scrutiny of the electric vehicle maker and automated systems that perform at least some driving tasks.

An engineering analysis is the final stage of an investigation, and in most cases NHTSA decides within a year if there should be a recall or the probe should be closed.

Documents posted Thursday by the agency raise some serious issues about Tesla’s Autopilot system. The agency found that it’s being used in areas where its capabilities are limited, and that many drivers aren’t taking action to avoid crashes despite warnings from the vehicle.

NHTSA reported that it has found 16 crashes into emergency vehicles and trucks with warning signs, causing 15 injuries and one death.

Investigators will evaluate additional data, vehicle performance and “explore the degree to which Autopilot and associated Tesla systems may exacerbate human factors or behavioral safety risks undermining the effectiveness of the driver’s supervision,” the agency said.

The agency found in many cases, drivers had their hands on the steering wheel yet failed to take action to avoid a crash, suggesting they are complying with Tesla’s system, the agency wrote. Yet this doesn’t necessarily make sure they’re paying attention.