The National Highway Traffic Safety Administration (NHTSA) said Thursday it is upgrading its probe to 830,000 Tesla vehicles. (TSLA.O) Vehicles equipped with an advanced driver assistance system on autopilot, a required step before you can request a recall.

The Auto Safety Agency in August opened a preliminary assessment to assess system performance in 765,000 vehicles after about a dozen accidents in which Tesla vehicles collided with emergency stops — and Thursday said Six additional incidents have been identified.

NHTSA is upgrading its probe to engineering analysis, which it should do before calling for a recall if necessary.

The Automotive Safety Regulator is reviewing whether Tesla cars adequately warrant the attention of drivers. The agency added evidence indicating that drivers in most of the crashes under review complied with Tesla’s alert strategy that seeks to get the driver’s attention, raising questions about its effectiveness.

In 2020, . was released National Transportation Safety Board Tesla criticized “ineffective monitoring of driver participation” after the fatal 2018 autopilot accident and said the NHTSA provided “little oversight”.

NHTSA saidupgrade It is “to extend existing collision analysis, evaluate additional data sets, perform vehicle assessments, and explore the degree to which autopilot and associated Tesla systems may exacerbate human factors or behavioral safety risks by undermining the effectiveness of driver supervision.”

Tesla, which has disbanded its press offices, did not respond to a request for comment.

NHTSA said it has reported 16 accidents, including seven injuries and one death, involving Tesla vehicles on autopilot that collided with stationary first responder vehicles and road maintenance vehicles.

Democratic Senator Ed Markey praised the NHTSA promotion. “Every day that Tesla ignores safety rules and misleads the public about its ‘autopilot’ system, our roads become more dangerous,” he wrote on Twitter.

The NHTSA said its analysis indicated that forward collision warnings were activated in the majority of crashes just before a collision and that Automatic Post-Emergency Braking was involved in nearly half of all crashes.

“On average in these accidents, the autopilot aborts control of the vehicle less than one second before the first impact,” the agency added.

The NHTSA noted that “if accident video was available, the approach to the first responder’s sight was visible to the driver an average of 8 seconds prior to impact.”

The agency also reviewed 106 reported autopilot accidents and said, in nearly half, “there were indications that the driver was not responding adequately to the needs of the dynamic driving task.”

“The driver’s use or misuse of vehicle components, or the vehicle’s unintended operation, does not necessarily prevent a system malfunction,” the agency said.

The NHTSA also found that in about a quarter of its 106 crashes, the primary crash factor appears to be related to the operation of the system as Tesla says restrictions may exist in places such as roads other than highways with limited access, or while in visibility environments that include factors such as rain or Snow or ice.

Tesla Autopilot says It allows vehicles to brake and steer automatically within their lanes but does not make them able to drive themselves.

A NHTSA spokesperson said advanced driving assistance features can enhance safety “by helping drivers avoid collisions and mitigate accidents that do occur, but as with all technology and equipment in cars, drivers must use them correctly and responsibly.”

Last week, NHTSA She said she asked Tesla to answer questions by June 20 after it received 758 reports of unexpected brake activation linked to Autopilot in its separate investigation of 416,000 newer cars.

Separately, NHTSA 35 has opened a special investigation into Tesla vehicle crashes, in which it suspected the use of Autopilot or other advanced systems including 14 deaths reported since 2016, including a crash that killed three last month in California.

NHTSA has requested dozens of other automakers including General Motors (GM.N) Toyota Motor Corporation (7203.T) and Volkswagen (VOWG_p.DE) To answer questions about ‘driver engagement and attention strategies’ using driver assistance systems’ during a Tesla test but did not issue their responses.

David Shepardson News. Editing by Bill Bercrot, Bernadette Bohm and Chizu Nomiyama

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