Funded by the insurance industry, the IIHS-which operates independently of the federal government-says that neither the BMW i3 nor the Tesla Model S performed well enough in its barrage of instrumented and measured tests to earn its top award. Those which also come with good or acceptable headlights, earn a "Top Safety Pick+" award. But it earned a lower rating in a small overlap frontal crash test, which replicates what happens when the front corner of the vehicle collides with a tree or telephone pole at 40 miles per hour. These features are essential in awarding a vehicle the Top Safety Pick + rating.
Despite changes made to its side curtain airbags, the Model S ranked only as "Acceptable" in the IIHS' demanding small overlap test.
Tesla told IIHS that it made a production change on January 23 to address the head-contact problem and IIHS will test the updated Model S for small overlap protection as soon as it can be delivered.
David Zuby, IIHS executive vice president and chief research officer, said the insurance group hopes Tesla and BMW will make improvements.
In the 2017 model year, 38 vehicles have won the "Top Safety Pick-Plus" designation, including two plug-in hybrids: the Toyota Prius Prime and the Chevrolet Volt.
However, the IIHS says that the i3 and Model S won't require extensive modifications like the up-for-a-redesign Leaf does.
The i3, a small auto, fails to reach the winner's circle because it rates only acceptable in the head restraint and seat evaluation, which measures a vehicle's ability to protect against neck injuries in a rear crash. There's a problem with the seat belt, apparently, because it allowed the dummy to move too much forward.
Unfortunately for Tesla, the 2017 Model S only achieved an "acceptable" rating in that particular test. The poor performance there is actually a side-effect of the car's longer range: Tesla added more batteries and thus increased the weight of the auto, IIHS argues, and thus even though the P100D has the same roof as its lighter range-mates, it will do worse in the vital strength-to-weight ratio that judges how well occupants might do in a rollover situation. The 2017 BMW i3 also failed to meet the institute's stringent standards.
One version of the Model S, the P100D, also falls short on roof strength, which is important for protecting people in a rollover crash.
Tesla's auto also wasn't judged on front crash protection, since the automaker is still in the process of activating the feature across HW2 cars. Tesla confirmed that it had fixed the problem, and wrote in an email that it would be beefing up its crash safety even further with an "automatic emergency breaking" feature, which will be rolled out as an over-the-air software update "in the coming weeks". IIHS will evaluate the new ones when they are available. The system reduced the impact speed by an average of 9 mph in the 12 mph track test and by 7 mph in the 25 mph test.
Ratings for crashworthiness and headlights are good, acceptable, marginal and poor. It's a shame that it missed the mark on head restraints, which is something most of today's vehicles get right.
The IIHS says it plans to test the Chevrolet Bolt EV electric auto soon.