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Fitment Guaranteed for 2018 Acura RLX

What Size Bulbs Does a 2018 Acura RLX Use?

Correct headlight, fog light, and tail light bulb sizes. Sourced from OEM catalog data.

Installation Difficulty

Moderate (Dust covers often present)

Est. Replacement Cost

$15 - $40 (Halogen) / $30+ (LED)

What Lighting System Does the 2018 Acura RLX Have?

The 2018 Acura RLX features a comprehensive lighting system with 10 bulb positions. It uses factory LED technology with integrated LED headlight modules. The RLX has been available from 2014 to 2020, and the 2018 model falls in the mid-generation years.

Can You Put LED Bulbs in a 2018 Acura RLX?

Upgrading the 2018 Acura RLX to LED headlights is straightforward since it uses a single LED Headlights dual-filament bulb for both low and high beams. You only need one pair of LED bulbs to upgrade both functions. Look for a LED Headlights LED kit that specifically supports dual-filament operation to ensure both beams work correctly. For the fog lights, a LED Fog Lights LED bulb provides a clean white output that pairs well with LED headlights.

How to Replace Bulbs on a 2018 Acura RLX

To remove the headlight bulb, disconnect the wiring harness, then twist the bulb counter-clockwise and pull it straight out of the housing. On the 2018 RLX, you will likely encounter rubber dust covers behind the headlight housing. These pull off by hand or unscrew depending on the design. Allow about 15 to 20 minutes per side. This vehicle has factory-integrated LED headlight modules. These are not user-serviceable bulbs. If your LED headlights fail, the entire headlight assembly or LED module may need to be replaced by a dealer or qualified technician. The fog lights are accessed from underneath the front bumper. You may need to remove a few plastic clips or screws from the fender liner to reach the LED Fog Lights fog light socket.

Full Upgrade Bundle

Upgrade All 10 Positions at Once

Low Beam: LED HeadlightsHigh Beam: LED HeadlightsFog Light: LED Fog LightsBrake Light: Brake Light AssemblySide Marker: LED BulbTurn Signal Front: LED BulbParking Light: LED BulbTurn Signal Rear: LED BulbReverse Light: LED BulbTrunk Light: 168
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How Long Do 2018 Acura RLX Headlight Bulbs Last?

Factory LED headlights on the 2018 Acura RLX are rated for approximately 25,000 to 50,000 hours of use, which translates to roughly 10 to 15 years of normal driving. LED modules rarely burn out suddenly. Instead, they gradually dim over time or develop dead zones within the LED array. At 8 years old, the original bulbs on your RLX are likely overdue for replacement, though LED modules may still have life left. Even if they still illuminate, reduced brightness significantly impacts nighttime safety. When one headlight burns out, replace both sides at the same time. Bulbs from the same batch age at similar rates, and mismatched brightness is distracting to oncoming drivers.

What Bulbs Are Compatible with the 2018 Acura RLX?

Using the wrong bulb size can cause improper beam patterns that reduce your visibility and blind other drivers. It can also cause overheating inside the headlight housing, potentially warping the plastic lens or reflector. Always verify the bulb number before purchasing.

2018 Acura RLX Headlight FAQ

The 2018 Acura RLX uses a LED Headlights bulb for the low beam headlights. We recommend upgrading to LED for better visibility.

The high beam bulb size for the 2018 Acura RLX is LED Headlights.

The 2018 Acura RLX uses a single bulb (dual filament) headlight system. This means one bulb controls both high and low beams.

Yes, the 2018 Acura RLX comes with standard halogen bulbs from the factory, but they can be upgraded to LED. You will need a LED Headlights LED conversion kit for the low beams.

Yes, the 2018 Acura RLX takes a LED Fog Lights bulb for the fog light position.

Turn off the vehicle and open the hood. Locate the headlight assembly from behind, remove the dust cover or retaining clip, disconnect the wiring harness, twist the old LED Headlights bulb counter-clockwise to remove it, then insert the new bulb and reassemble. The whole process typically takes 10 to 30 minutes per side depending on accessibility.

LED bulbs used off-road or in auxiliary lights are legal everywhere. For on-road headlight use, legality varies by state. Many states allow LED retrofits as long as the beam pattern meets DOT standards. For the best legal compliance, choose a DOT-approved LED Headlights LED kit that is designed as a direct replacement and produces a proper cutoff pattern without excessive glare.

A pair of halogen LED Headlights bulbs costs $15 to $40, while LED conversion kits run $25 to $60 per pair. If you have a shop do the work, expect an additional $20 to $50 in labor per bulb. Replacing them yourself at home saves the labor cost and usually takes under 30 minutes.

Halogen bulbs produce a warm yellow light (around 3200K), last 500 to 1000 hours, and draw more power. LED bulbs emit a brighter white light (5000-6000K), last 25,000+ hours, and use less energy. LED upgrades for the LED Headlights position are available as direct plug-and-play replacements.

Did Acura RLX Bulb Sizes Change Over the Years?

Over its production run from 2014 to 2020, the Acura RLX has seen bulb size changes in the Brake Light, Turn Signal Front and Parking Light positions. The 2018 model uses the newer bulb specification introduced around 2017. Always verify the exact bulb size for your specific 2018 model year using the chart above, as using the wrong size can result in poor fitment or reduced light output.

Other RLX Years