1979-86 Mustang Headlight Relay Harness by 5.0 Resto

Price: 44.99 USD
Availability: InStock

***79-85 Mustang Wiring Layout***

***1986 Mustang Wiring Layout***

5.0 Resto's headlight relay harness is a must for all 1979-1986 Fox Body Mustang owners to prevent dim lights and melted connectors.

Item #LRS-14489-HR79

Everyday Low Price: $44.99

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***79-85 Mustang Wiring Layout***

***1986 Mustang Wiring Layout***

LMR showroom & will call pickup service will be closed beginning Monday 9/21/26 for renovations until further notice. Need help? Contact Us.

Benefits

Reduces Headlight Circuit Amp Draw
Plug & Play Design
Easy Installation

Features

Durable Plastic Connectors
Flexible Polyethylene Tubing
Insulated Wiring

What's in the Box

(1) Headlight Relay Harness

5.0 Resto Headlight Relay Harness
From the factory, there was a slight overload on the headlight circuit that, over time, can cause serious damage to the headlight switch connector that plugs into the back of the headlight switch due to the large amp draw. The connector can melt, which can cause damage to the switch, dash wiring, and intermittent headlight function. Well, thanks to 5.0 Resto, you no longer have to worry about that; the headlight relay harness will prevent this issue in the future. The 5.0 Resto headlight relay harness shifts the load away from that connector into two relays, one for the low beam and one for the high beams. Reducing amp draw anywhere from 5-10 amps per circuit greatly decreasing the demand on the factory wiring. Regardless of whether you have good factory wiring, are doing a mild restoration, or are just working on making your Fox Body further updated, this harness is a fantastic option for your Mustang. We believe every single 1979-1986 Mustang needs this harness, as this is how it should have been wired from the factory.

5.0 Resto Quality
5.0 Resto products are designed and manufactured with OEM fit and finish in mind, and this headlight relay harness is no exception. Prewired using two 40-amp relays with individual fuses for each relay in their own protective case. Featuring thick crosslink automotive-grade wire to carry the load throughout with durable protective insulation. All of the connectors are constructed from durable plastic with the proper tabs, seals, and alignment slots for easy installation. The entire harness is wrapped in protective flexible polyethylene tubing, maintaining a factory-correct look. Finished off with high-quality heat shrink on all of the ring terminals helping protect them from corrosion.

Simple Installation
The 5.0 Resto headlight relay harness main red power wire hooks directly up to the battery side of the starter relay, and the harness will snake down along the frame rail exiting the front of the core support. This is where you can choose the location to mount the relays, using an existing location on the core support or driver-side inner fender. The female connector will plug directly into the driver-side factory headlight sockets, and the new driver-side male connectors will plug into the headlights. The passenger-side relay harness connectors will go across the core support, where they connect to the headlights. The ground wires on each side snake up to the top of the core support, where they attach to the factory grounds. All that is left is to wrap and seal up the factory passenger-side headlight sockets.

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About This Brand

5.0 Resto - Dedicated To The Preservation Of The Fox Body Mustang
5.0 Resto® is the one and only brand dedicated to the restoration and preservation of 1979-1993 Fox Body Mustangs. Specializing in designing and manufacturing problem-solving solutions, 5.0 Resto® provides superior restoration products for the Fox Body Mustang community to ease the restoration of the beloved platform. A brand built on automotive enthusiasts, 5.0 Resto® is driven to deliver convenience by offering premium products that save the customer time and money with a complete solution to eliminate all uncertainty. Through extensive research and development, rest assured that each and every 5.0 Resto® product is made from the highest quality materials for an industry-leading fit and finish.

Be sure to shop for all 5.0 Resto® Fox Body Mustang Parts exclusively at LMR.com