Free Shipping on all order over $99.99

6418 38mm Festoon LEDs

Replace compatible dome, map, glove box, footwell and license plate bulbs with Underground Lighting 6418 LEDs. The exact 38mm festoon design provides brighter output, lower power consumption and CANbus-ready operation for supported vehicle circuits.

View as

  • 45 Day Returns

    Hassle-free & easy

  • Talk to a Specialist

    Call us (561) 918-5225

  • Free Shipping

    On orders over $89.99

  • Ships Same Day

    If order is placed before 2PM EST

2000+ Verified Reviews

With a 4.95 average rating across Google and Judge.me, Underground Lighting has earned the trust of drivers looking for dependable LED lighting upgrades. See why customers choose us for fitment support, quality products, fast shipping, and brighter lighting solutions for cars, trucks, and SUVs.

6418 38mm Festoon LED Bulbs | Interior, Dome & License Plate LED Upgrades

The 6418 bulb is a 38mm festoon-style interior automotive bulb (C10W format) widely used in dome lights, glove box lights, map lights, footwell illumination, and license-plate lighting across many European and Japanese vehicles. It installs via bullet-shaped metal end caps that seat into spring-loaded festoon clip sockets, making exact 38mm length compatibility critical for electrical contact and retention.

  • SMD chip types: 2835 / 5050
  • Chip count: Typically 3–6 for a 38mm festoon
  • Voltage: 12V DC automotive
  • Power draw: Approximately 1–2W

This Underground Lighting collection contains 6418 LED replacement bulbs, upgrading the original approximately 5W incandescent festoon to a solid-state LED lighting system operating on the standard 12V DC automotive electrical circuit. LED festoon bulbs use surface-mount diode (SMD) chips such as 2835 or 5050 packages, delivering higher brightness while drawing only approximately 1–2W and producing minimal heat compared with filament bulbs.

The collection includes the core product:

6418 38mm 3-SMD CANbus Error-Free Festoon LED Bulbs

Compact 38mm LED festoon bulbs with integrated CANbus load circuitry to help prevent bulb-out warnings in license-plate or door-monitored lighting circuits. Designed for precise 38mm housings and interior applications requiring stable output and low heat.

Typical LED output for 6418 festoon bulbs ranges from approximately 80–220 lumens, depending on chip density and optical spread. Lower-output LEDs are recommended for map or glove-box lighting, while higher-output LEDs improve dome or footwell visibility.

Functional Applications & Housing Compatibility

Dome / Cabin Light
Ceiling-mounted interior lighting requiring a wide beam spread. Underground Lighting LED upgrades increase cabin brightness and longevity.

Glove Box Light
Small enclosed compartment lighting. LED festoon bulbs improve reach and clarity with lower heat buildup.

License Plate Light
Exterior rear plate illumination requiring white LED output, approximately 5000–6000K, for regulatory compliance. CANbus festoon LEDs help prevent dashboard bulb-out warnings.

Footwell / Courtesy Light
Under-dash or door-mounted lighting enhances entry visibility and interior styling.

Map / Reading Light
Directed overhead light for the driver or passenger. Diffused or lower-lumen LED output reduces glare in clear lenses.

All 6418 bulbs are installed using clip-in festoon mounting. Compress one end into the spring clip and seat the opposite end cap. Because festoon LEDs can be polarity-sensitive, rotate the bulb 180 degrees if it does not illuminate, unless using non-polarity circuitry.

Exact Size & Cross-Fit Clarification

Festoon bulbs are length-specific and not interchangeable:

  • 6418: 38mm
  • 6413: 36mm
  • 6411 / 578: 42mm
  • 212-2: 44mm

Even a 2mm variation can cause loose contact or non-fitment in festoon housings.

LED Technology & Color Options

Available LED color temperatures:

  • Warm white, approximately 3000K: Comfort or classic interior tone
  • Neutral white, approximately 5000K: Balanced OEM look
  • Cool white, approximately 6000K: Modern, crisp illumination

Exterior license plate use requires white only.

Explore our comprehensive lighting catalog, featuring HIDs, LEDs, and Forward Lighting solutions built for maximum brightness and durability.

From Headlight and Fog Light Bulbs to Reverse Lights and Brake/Tail Lights, we have every major lighting category covered.

Customize your vehicle with LED Strobes, LED Rolls, Rock Lights, Underground Lights, and Auxiliary lighting setups.

Complete your upgrade with HID Bulbs, Ballasts, Conversion Kits, and all essential lighting accessories.

Check compatibility with the Bulb Finder and upgrade your ride today.

Benefits of Underground Lighting 6418 38mm LED Festoon Bulb Upgrades

  • 2–4× Brighter Interior Illumination

    Underground Lighting 6418 festoon bulbs deliver approximately 80–220 lumens compared with around 40–70 lumens from halogen bulbs, improving dome, footwell and compartment visibility.

  • Up to 60 % Lower Power Consumption

    Underground Lighting LED festoon bulbs draw approximately 1–2W compared with around 5W for incandescent bulbs, reducing electrical load in compatible interior and license plate circuits.

  • Minimal Heat Protects Lens & Housing

    Cooler LED operation helps prevent plastic lens discoloration and deformation in compatible enclosed dome, glove-box and license plate fixtures.

  • Exact 38 mm Festoon Fitment Stability

    The correct 38mm Underground Lighting bulb length supports firm clip-mount contact, helping prevent flickering or intermittent connections caused by incorrectly sized festoon bulbs.

  • CANbus Error-Free License Plate Operation

    Integrated load circuitry helps reduce bulb-out warnings when Underground Lighting 6418 LEDs are installed in compatible BCM-monitored license plate or door-lighting systems.

  • Long LED Lifespan (20,000–50,000 Hours)

    Solid-state Underground Lighting festoon LEDs can last considerably longer than filament bulbs, reducing replacement frequency in frequently used interior and license plate fixtures.

How to Choose the Right 6418 38mm Festoon LED Bulb

Confirm the 38mm festoon size, then match the bulb to the housing, brightness needs, color, and vehicle electrical system.

  • Check length: Verify the bulb is exactly 38mm.
  • Confirm clearance: Make sure the LED board fits inside the housing.
  • Choose brightness: Higher output suits dome or footwell lights; lower output may be better for smaller fixtures.
  • Check orientation: Position flat LED panels toward the lens or reflector.
  • Use CANbus if needed: Monitored circuits may require an error-free bulb.
  • Choose the right white tone: Warm, neutral, or cool white based on the application.

Watch these helpful Underground Lighting videos for step-by-step guidance, product details, and real-world installation tips.

Find the Right 6418 LED Bulb for Your Vehicle

Vehicle Part Search

Call us at (561) 918-5225 or Send an Email

6418 38mm Festoon LED Bulb FAQs

A 6418 bulb is commonly cross-referenced with the C10W festoon format, but the C10W designation can cover similar festoon bulbs with different lengths. For correct fitment, confirm that the original bulb measures approximately 38mm from metal end cap to metal end cap and matches the vehicle socket.

6418 38mm festoon bulbs are commonly found in selected European and Japanese vehicles, particularly in dome lights, map lights, glove-box lights, courtesy lights, footwell lighting, and license plate housings. Fitment can vary by model year, trim, and lighting position, so the original bulb number and physical length should always be confirmed.

It may, depending on how the vehicle controls dimming. Some systems gradually reduce voltage, while others use pulse-width modulation.

An incompatible LED may flicker, switch off abruptly, or fade differently from the original filament bulb. In vehicles with theatre-style dimming, testing one bulb first is a practical way to confirm compatibility before replacing every interior light.

6418 38mm festoon LED bulbs typically cost around $10 to $20 per bulb, depending on LED-chip design, brightness, CANbus compatibility, integrated resistance, construction quality, and package quantity. Basic replacements are generally less expensive, while CANbus-ready or higher-output versions usually cost more.

Yes, in many cases a CANbus-style 6418 bulb can still operate in a standard 12V socket if the bulb size, polarity, and electrical specifications match. However, the added load circuitry is unnecessary in an unmonitored circuit and may generate additional heat.

A standard LED is usually sufficient when the vehicle does not produce bulb-out warnings or diagnostic pulses.

Yes, provided the fixture uses a compatible 38mm festoon socket and has enough clearance for the LED board and end caps. Higher-output bulbs can improve visibility in cargo or trunk areas, but the original bulb length should be checked carefully because some vehicles use 36mm, 42mm, or 44mm festoon bulbs instead.

No, not unless the specific bulb is rated for 24V operation. A 12V LED connected directly to a 24V circuit can be damaged by the higher supply voltage.

Always check the bulb voltage rating, fixture label, or vehicle documentation before installation, especially in commercial trucks, buses, trailers, and RV electrical systems. The 6418 product on this collection is specified for 12V DC automotive use.

Some vehicles send short diagnostic pulses through monitored lighting circuits to check whether a bulb is functioning. LEDs respond much faster than filament bulbs, so these pulses may appear as a brief flash.

This does not necessarily indicate a defective bulb. A compatible CANbus or error-free LED can help reduce this behavior in some monitored circuits.

No. Festoon bulbs are length-specific, and even a small difference can cause loose electrical contact or prevent the bulb from fitting properly. A 6418 replacement should match the original 38mm length rather than being substituted with a 36mm or 42mm festoon bulb.

Back to top
Compare /3