Some drivers who complained their Toyotas suffered from unintended acceleration may have been mistaking the throttle pedal for the brake.
The initial investigation by US authorities studied the data recorders on cars involved in accidents and discovered that in many cases the brakes had not been engaged prior to a collision.
The early findings of a National Highway Traffic Safety Administration study do not absolve Toyota from the sticking accelerator pedals and faulty floor mats that triggered its global recalls, but they do suggest that reports of sudden unintended acceleration were not due to a technical fault.
Despite thousands of complaints and several high profile accidents, the Japanese manufacturer has maintained that there was no issue with the computer-controlled throttle on its cars.
Toyota has not been involved in the recent findings, and it is unclear how many data recorders the NHTSA has studied, but it is thought to be focusing on recent accidents where the driver claimed to have stepped on the brakes before a collision.
The agency has refused to comment on the results of its investigation until the wider study (conducted with NASA) is published, but the NHTSA's associate administrator for enforcement, Daniel Smith, told the National Academy of Sciences that they had not yet found any defects on the cars beyond the faults already acknowledged by Toyota.
The probe is expected to take months to complete.
Source: The Wall Street Journal