Walter Huang, an Apple engineer, died after his car hit a barrier.
Tesla had also revealed that logs from the vehicle's computer had indicated that the 38-year-old's hands were not on the steering wheel in the six seconds prior to the collision on California's Route 101. It said the car had provided several "hands-on" warnings earlier in the journey.
In addition, it said that the safety barrier involved had been crushed and not replaced after an earlier accident, meaning it would not have been able to reduce the force of the impact as intended.
"At this time the NTSB needs the assistance of Tesla to decode the data the vehicle recorded," responded the agency's spokesman Chris O'Neil in a statement first published by the Washington Post.
"In each of our investigations involving a Tesla vehicle, Tesla has been extremely co-operative on assisting with the vehicle data.
"However, the NTSB is unhappy with the release of investigative information by Tesla."
"We've been doing a thorough search of our service records and we cannot find anything suggesting that the customer ever complained to Tesla about the performance of Autopilot," a spokeswoman told the BBC.
"There was a concern raised once about navigation not working correctly, but Autopilot's performance is unrelated to navigation."