These features are essential in awarding a auto the Top Safety Pick + rating. However, the results showed that Model S got an "Acceptable" rating in the small overlap front crash. The test is created to highlight any issues in front structural protection.
The vehicles headlights also fell extremely short, recording a "poor" rating when tested.
For its part, Tesla says that a fix which should address the problem is already in the pipeline.
Tesla says it made a production change on January 23 to address the problem.
It's the little things that brought misfortune to the Model S and i3 in this round of IIHS tests.
Still, it's not the only blot on Tesla's score book.
One version of the Model S, the P100D, also falls short on roof strength, which is important for protecting people in a rollover crash. This is due to the added weight of the P100D's larger battery, since this test uses the weight of the vehicle to determine how much force the roof can withstand.
Former minister E Ahamed suffers heart attack in Parliament, critical
He was rushed to Ram Manohar Lohia Hospital, where he has been under intensive care and on life support. E Ahmed has been a Lok Sabha member from Malappuram Lok Sabha constituency of Kerala since 1991.
The group, which represents the insurance industry, measures crashworthiness in five areas - small-overlap front, moderate overlap front, side, roof strength and head restraint. That began at the beginning of 2017, and is expected to roll-out progressively as Tesla monitors real-world feedback for any signs of potential problems. However, the Insurance Institute for Highway Safety (IIHS) says that it failed to meet the requirements of the fifth test, which apparently is the most demanding.
It's not just Tesla which is having a bad day courtesy of the IIHS, mind. That looks at how well a vehicle protects against neck injuries, in the case of a rear crash.
The government hasn't yet reported crash-test results for the i3. For its headlights, the i3 earned the rating of "acceptable", which is the second highest level. The plug-in hybrids came out on top.
Two of the most prominent electric cars have missed out on the highest award given for vehicle safety by the influential IIHS: Top Safety Pick+. Toyota's hybrid does well with all its standard safety systems.
"The seatbelt force limiter and airbag did not work together quite the way we think is good for this type of crash", said David Zuby, IIHS' chief research officer.
This Sept. 20, 2016, photo provided by the Insurance Institute for Highway Safety shows a 2017 BMW i3 before crash safety testing. They can be just as safe as any other vehicle on the road.
The IIHS was otherwise more complimentary of the i3, which it says has LED headlights that rank as "Acceptable" (enough to qualify for Top Safety Pick+) and an automatic emergency braking system rated as "Advanced". In the other four tests conducted, the auto managed to get a "good" rating.