Curiously, the base-model headlights earn a 'good' rating while the more expensive Premium Triple Beam LEDs are rated 'marginal.'
The Lexus RC has returned to the Top Safety Pick+ ranks for the 2018 model year.
The nameplate has received 'good' ratings in all crash scenarios since its introduction in 2014. A few upgrades were required more recently, however, as the Insurance Institute for Highway Safety rolled out more stringent requirements for the TSP+ honor roll.
The 2018 RC adds a new front crash prevention system that moves from an 'advanced' to a 'superior' rating, completely avoiding collisions at 12mph and 25mph. It is also now a standard feature instead of an optional upgrade.
The sedan has also received standard high-beam assist, upgrading its base-model headlight performance from 'acceptable' to 'good.'
Most buyers will expect the optional Premium Triple Beam LED headlamps to offer better lighting to justify a higher price. The IIHS tests show that performance actually decreases, however.
"The more expensive headlights provide much less visibility than the standard ones, likely due to an aim problem," the institute said. "Vehicles that come out of the factory with misaimed headlights are a frequent problem, resulting sometimes in poor visibility and sometimes in excessive glare."