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Daniel Gray - Mar 16, 2020 2:06 pm UTC

It might be stating the obvious, but your car's headlights are a safety device, and not all headlights are created equal. For a while, carmakers have been fitting powerful LED headlights to their high-end offerings, but more often than not, their cheaper cars—and particularly cheaper trim levels—get saddled with much-weaker illumination. But sometimes a commuter wants to see more of where they're going when the sun goes down. Eventually, they go looking for a solution, starting with their local automotive parts store. But stuffing aftermarket LED headlight bulbs into OEM housings designed for conventional halogen units results in dangerous glare for oncoming drivers. While LEDs can deliver more intense light at a higher end of the spectrum, most aftermarket units also create a hazardous condition.

The major brick-and-mortar auto parts stores know this, which is why they tend to shy away from aftermarket H11 LED bulbs, other than ones clearly marked for use in fog lamps or "for off-road use only." It's a different world online, with off-brand H11 LED bulb listings on Amazon, eBay, and Walmart websites failing to carry the same prominent warnings.

You can get pulled over for non-spec headlamps, and for a good reason. In addition to issuing a citation, the law enforcement officer may have the legal right to force you to remove the bulbs. More ominously, once the officer has pulled you over, you risk a vehicle search. With all that in mind, it would be wise to keep a set of securely packaged OEM bulbs in the glovebox or trunk if you are running aftermarket LEDs.

Although Consumer Reports tests new vehicle headlamps, it hasn't tackled the topic of LED replacement bulbs, despite Consumer Reports' extensive resources. A comprehensive Consumer Reports aftermarket LED replacement bulb test would go a long way to bring clarity to the market. Consumer Reports' testing of conventional replacement bulbs found that while aftermarket units can improve headlight brightness, there's much more to it than that. "Distance and how far a headlight illuminates is governed more by the reflector (behind the bulb) or the lens (ahead of the bulbs). While you can change the bulb, you are not changing the distance, i.e., not necessarily improving safety."

Do your lighting research before you make your next vehicle purchase. Headlamp technology has typically been bundled with the trim level. The base model would get fitted with reflector headlamps, with projectors offered in the mid-range and higher trim levels. Adaptive headlights have been the preserve of the top trim levels. All that means that less-expensive vehicles are often stuck with reflectors across the range in America. (IIHS recently changed its testing rules and will now only give its coveted Top Safety Pick+ to models that offer the best headlights across all trim levels.)

The Ford Fiesta is a case in point. While self-leveling projector headlamps are available in the Fiesta ST overseas, Ford saddled domestic Fiesta STs with poorly performing reflectors.

Fiesta owners got stuck between a rock and a dark place. While they can adapt an expensive imported OEM projector housing, those housings lack side marker lights, making them illegal for domestic use. The lack of a proper solution forces Fiesta ST owners looking for LEDs to stuff LED replacement bulbs into the original reflector housings, for better or for worse.

Although bulb replacement is relatively quick and easy, the crucial process of beam alignment often gets overlooked. Consumer Reports stressed that "headlamp alignment is key to limiting/controlling glare to oncoming and followed drivers."

LED bulbs make the problem worse. While halogen filaments deliver 360-degree illumination, LED bulbs typically emit light with a pair of back-to-back 180-degree planes. When LED alignment gets skipped, oncoming drivers are blinded, as are drivers ahead of them in traffic. Poorly aimed headlamps are especially bothersome with pickup trucks and SUVs due to the vehicle height.

If you choose to install aftermarket LEDs, do your homework. Find a reputable manufacturer and domestic retailer. Buy based on quality, not price. The optimal LED replacement bulbs mimic OEM halogen filament bulbs as closely as possible. The worst bulbs are a stab in the eyes. And don't skip alignment—take your time and do it right.

Aftermarket LED replacement bulbs are illegal, but there's little enforcement at the federal level. We checked in with NHTSA and a spokesperson told us the following:

"There are currently no LED headlamp replaceable bulbs that meet federal safety standards. NHTSA is aware of illegal retrofit kits that are being sold to consumers and works closely with US Customs and Border Protection to prevent shipments containing these non-compliant headlamp bulbs from entering the United States. NHTSA continuously researches emerging technologies with the potential to enhance roadway safety."

The legit aftermarket industry wants to do the right thing. As an example, Holley recently introduced a line of Bright Earth LED replacement headlamp bulbs. Holley's online sales pages include a proper and prominent disclaimer:

WARNING: THIS REPLACEMENT LED HEADLIGHT BULB SET IS SOLD FOR OFF-ROAD USE ONLY. This product should not be used on the road. This product has not been tested for compliance with United States Federal Motor Vehicle Safety Standard FHMVSS 108 or Canadian Standard CMVSS108. It should not be used on the road or in any other application requiring compliance with FHMVSS 108, CMVSS108, or Title 49 section 571.108, United States Code.

The biggest online retailers need to catch up. While some sellers include a disclaimer that aftermarket LED bulbs shouldn't be used on the street, Amazon sales pages do not.

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