Consumer Reports said Tesla's Smart Summon feature worked inconsistently and questioned the benefits owners receive from it in a review published on Tuesday.
The publication found that the feature, which allows a vehicle to drive to its owner in a parking lot or driveway, would appear at times to be confused by its environment, stopping or deactivating without having a clear reason to do so. Sometimes, the feature directed the publication's Model 3 sedan to drive in the middle of a lane in a parking lot, rather than on the side of the lane closest to the parked cars, or steer erratically, "like a drunken or distracted driver." At one point, Smart Summon directed the Model 3 to drive in the wrong direction down a one-way lane.
Smart Summon did work as intended in some circumstances, Consumer Reports said, and drove conservatively, which the publication said had positive implications for safety.
Tesla did not respond to multiple requests for comment from Consumer Reports, the publication said. The electric-car maker also did not immediately respond to Business Insider's request for comment.
Tesla began to roll out Smart Summon as part of a software update at the end of September. Some Tesla owners have expressed excitement about the feature's performance, while others have posted videos showing the feature malfunctioning. Regulators have taken notice, as the National Highway Traffic Safety Administration (NHTSA) has said it is looking into the feature and communicating with Tesla.
"Safety is NHTSA's top priority and the agency will not hesitate to act if it finds evidence of a safety-related defect," a NHTSA representative said last week.
Tesla has attracted controversy over the ways it has marketed and discussed self-driving technology. The company's CEO, Elon Musk, has said the company will have autonomous-driving technology that requires no human intervention ready by the end of next year, a more aggressive timeline than those announced or suggested by other auto or tech companies.
Musk has also ignored Tesla's guidelines for customers when using its Autopilot feature — which can control steering, accelerating, and braking in some circumstances, but requires the driver to keep his hands on the wheel and eyes on the road — on television.