The report issued on Thursday by the National Transportation Safety Board (NTSB) said Walter Huang, the driver of the 2017 Model X using Autopilot, had been given two visual alerts and one auditory alert to place his hands on the steering wheel during the trip - but those alerts came more than 15 minutes before the March 23 crash. After hitting the attenuator, the Tesla hit two other cars.
According to the NTSB report, the driver did not put his hands on the steering wheel of the vehicle for six seconds prior to the crash, despite having had his hand on the wheel for 34 seconds of the preceding minute.
He died in hospital soon after the crash.
The NTSB report notes some other significant details about the vehicle and how fast it was going.
Four seconds before the crash, the Tesla no longer detected a vehicle in front of it, and with the cruise control engaged and set at 75 mph, it began speeding up, from 62 mph three seconds before impact to 70.8 mph at the time of impact. Consumer groups argue Tesla's marketing - and even the name "Autopilot", which calls to mind a free-flying jet - contributes to a unsafe misunderstanding for drivers, suggesting they can take their hands off the steering wheel.
In the days after the crash, Huang's wife Savonne said her husband had complained about the system not working properly near the area where the crash occurred.
"The Autopilot system should never have caused this to happen".
The video poster says a friend filmed the video earlier this week near Fremont, California where Tesla is based.
A Tesla spokeswoman pointed to passages in the company's owner's manual that warn that automatic emergency braking may not work all the time, and won't save the driver from an accident.
On Tesla's website, it describes upcoming features - including the ability for a vehicle to change lanes without driver input, move from one freeway to another, and exit a freeway near the driver's destination - that are not available in Autopilot's current iteration. In January, a Tesla Model S that may have been on autopilot hit a parked firetruck on Interstate 405 near Los Angeles.
Federal investigators determined the car's semi-autonomous Autopilot driving system accelerated to 71 miles per hour seconds before the crash in California, killing its driver Walter Huang, 38.
On Tuesday, Musk said Tesla would give free trials of Autopilot to Tesla owners who didn't purchase the feature (it costs between $5,000-$6,000) and have the necessary hardware to run it "hopefully next month". The SUV also was equipped with automatic emergency braking, which is always on in Tesla vehicles unless customers deactivate it by taking several steps on the vehicle touch screen.
Tesla declined to comment on the NTSB report and did not immediately comment Friday, but said in March that Huang had not braked or taken actions to avoid the crash in the final seconds before the accident.
The report said the SUV was operating with "traffic-aware cruise control" before the crash.
"The impact rotated the Tesla counter clockwise and caused a separation of the front portion of the vehicle", the report said. 'The focus is on what led to this crash and how do we prevent it from happening again'.