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Exterior Components› Lights and Components

Morimoto

HID Lighting Power Harness

Name: HID Lighting Power Harness
Brand: Morimoto
SKU: H40
Price: 66.00 USD
Availability: InStock

$66.00

SKU: H40

In Stock

Ships by Nov 7

Free Shipping over $200

$100 Minimum Order

Non-Returnable Item

DIY PRO SHOP

Easy — 1–2 hours

Overview

This harness is crucial for a reliable HID lighting upgrade, ensuring consistent power delivery.

Show original supplier description

The Morimoto HD Relay harness is an essential component for any HID lighting upgrade, ensuring steady and consistent voltage delivery directly from the vehicle's battery to your HID ballasts. This plug-and-play solution effectively eliminates headlight flicker and voltage drops that can occur when relying on factory headlight outputs, which are often insufficient for HID systems. Constructed with durability and performance in mind, the Morimoto HD Relay features wiring protected by abrasion-resistant Techflex mesh sleeving and OEM-style relay cubes. The relays themselves are sealed against the elements with ribbed silicone seals and include a flywheel diode for back-EMF protection, while other connections are secured with silicone grommets. This versatile harness is compatible with H11, H9, H8, and 880 bulb types and can be used for low beams, high beams, or fog lights. It utilizes industry-standard outputs for broad compatibility with most HID ballasts. For vehicles equipped with CANBUS systems or finicky pulsed headlight circuits, separate harnesses like the Standalone Canbus or Mopar Spec are required and not included. Additionally, BI-XENON projectors will require High Beam Splitters, and PWM pulsing signals necessitate a Capacitor Link, neither of which are included with this harness. The unit includes an inline 25A fuse for safety and is backed by a 2-year warranty.

Vehicle Symptoms

Headlights flicker at idle or startup
HID lights dimming under load
One headlight randomly shuts off
Flickering on cold start before warm-up
Headlight brightness drops when engine revs

Relevant Conversations

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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

Brand	Morimoto
Part Number	H40
Category	Exterior Components

Videos

MORIMOTO RELAY HARNESS INSTALLATION - ITS EASY!

TRS Tech: Morimoto Standalone Canbus Error-Cancelling HID Harnesses

TRS Tips: How to Install Morimoto Elite HID System with Standalone Canbus Harnesses

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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