HD Relay: H11

1 Review

Brand: Morimoto


$44.63 Original Price:$52.5015% OFF


PART #: 1 x H40

Easy Return


Introducing the HD Relay Harness - the ultimate solution for your HID lighting upgrade. Say goodbye to flickering headlights and subpar wiring issues. Our relay harness delivers a steady voltage directly from your car battery to the HID ballasts, ensuring a consistent and powerful light output. Don't compromise on quality; choose a harness that's designed to match the performance of your premium ballasts and bulbs. Installing the HD Relay Harness is a breeze, thanks to its plug-and-play design. Whether you drive a compact car or an SUV, the harness's versatile wire lengths have you covered. With one relay per side, this harness guarantees fail-safe operation, even in challenging weather conditions. Elevate your vehicle's lighting game with the HD Relay Harness - where reliability and performance meet style under the hood.


  • Steady Voltage: Ensure consistent HID ballast performance with direct battery power.
  • Flicker-Free Illumination: Bid farewell to bothersome headlight flickering.
  • Plug-and-Play Installation: Effortlessly set up with simple connections, no splicing required.
  • Fail-Safe Design: Individual relays per side prevent complete headlight blackout.
  • Wide Compatibility: Suitable for low beams, high beams, and fog lights in most vehicles.


  • Harness: 1x HD Relay Harness

  • Input Adapter: 1x H11/H8/H9 Harness Input Adapter

  • Note: One harness controls both headlights


This Morimoto product includes a 2 Year limited warranty, serviced and supported by the Morimoto team in Atlanta, GA. This warranty does not cover modifications, alterations, or misuse. For additional information, Click Here.


  • Input: 1x H11 Male

  • Output: 2x 9006 Female

  • 12V Power: 1x Nickel-Plated Ring Terminal

  • Fuse: Inline 20A



  • HID SYSTEMS: Low Beams, High Beams, or Fog Lights

  • BI-XENON PROJECTORS?: You'll need High Beam Splitters

  • PWM PULSING SIGNAL?: You'll need a Capacitor Link

  • CANBUS SYSTEM?: Use Standalone Canbus or the Mopar Spec harnesses


Reality Check: Customers often ask, Do I really need a harness? Yes! A relay harness is designed to deliver steady voltage to your HID ballasts directly from the car battery. Nobody likes a flickering headlight, so why risk it? Factory headlight outputs are really only designed to power a halogen light bulb, not an HID ballast.

Don't Skimp: As one of the most important parts in any HID lighting upgrade; don't skimp out when it comes to your wiring. It doesn't matter how good your ballasts are. how good your bulbs are. If your harness is a piece of crap: when it gives out your headlights are gonezo. The Morimoto HD Relay harness is easily worth the premium price compared to cheaper alternatives.

Plug n Play: The layout of the harness makes it easy to install. With just a few simple connections, even your mom could set this thing up! Wire lengths are long enough to be used in everything from compact cars to SUVs and it's designed to be 100% plug and play (no cutting or splicing needed). Its connections are explained in this video.

Compatible: The HD relay can be used for low beams, high beams, or fog lights on most vehicles. The harness uses industry-standard outputs for compatibility with 99% of ballasts out there, and all of the ones we offer here at TRS. Note, if your vehicle has a can-bus system or a finicky pulsed headlight circuit - check out our Standalone Canbus or the Mopar Spec harnesses.

Fail-Safe: Unlike most generic harnesses out there that rely on a single low-quality relay to power both headlights, the Morimoto Harness utilizes one relay per side- so if one did happen fail, you wouldn't be left completely in the dark. Each 40A relay is completely sealed against the elements using ribbed silicone upper and lower seals, and has an flywheel diode for back-EMF protection. Every other connection harness-wide is sealed with the proper silicone grommets. Live somewhere with weather that regularly sucks? No problem.

OEM Grade: Aside from being ahead of the game from a technical standpoint, the HD relay is also a work of art. With it's wiring protected by abrasion-resistant Techflex mesh sleeving and OEM-style relay cubes held together by a mounting bracket cut from polished stainless - the HD relay will look factory fresh under the hood!

Overview Video: Check out this helpful video to see how easy a relay harness install is!

Ratings & Reviews

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Now thats a relay hardness


This hardness has saved me once before, glad I had it to begin with, a must have for that safety net you need. Great quality.

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