US to probe Tesla's 'Full Self-Driving' system after pedestrian killed in low visibility conditions

The video discusses Tesla's Full Self Driving feature, an $8000 upgrade requiring drivers to remain attentive. The National Highway Traffic Safety Administration (NHTSA) is investigating four accidents involving this feature, including a fatal pedestrian incident. Each accident occurred in areas with reduced visibility.

Describe the circumstances of the accident where a Tesla vehicle struck a pedestrian.

What common factor was present in each accident involving the Full Self Driving feature?