H6054 LED Headlight H4 Relay Harness for Jeep Toyota Subaru 9003

I installed this kit on my '96 Tacoma over a year ago and it's been rock-solid ever since. I'm very happy with it. I bought it so that I could get away from the old old style sealed headlamps and adopt something more modern without changing the look of the vehicle. I opted for the Hella Vision Plus, which uses modern halogen bulbs that draw too much current for the original wiring. Enter this kit to solve the problem. Toyotas have a unique headlight wiring design that necessitates a compatible kit like this one, and it delivers. I like that the relays are totally solid, the wiring is easy, and the engine bay remains very clean. The components and wiring fit nicely right along the fender near the fuse box and the performance has been excellent, without any flickering and definitely without causing any stress to the original wiring, which carries far less current now -- just enough to power. The relays is all. Although this kit should work with any lighting solution you choose to add, I can also recommend the brightness and greater visibility provided by the Hella Vision Plus kit. I wish you the best of luck as you seek to upgrade the headlights on your vehicle.

Vehicle: 1996 Jeep Cherokee Classic Overview: My headlight switch failed because it provides power to the headlights high/low beams through a factory wiring harness which is underpowered. The factory wiring harness is also the culprit of your dim lights. In my case, the headlight switch burnt up leaving me with no lights. Solution: I replaced the faulty switch and decided to upgrade to the H4 wiring harness. The H4 harness re-routes power to the headlights from the switch to the battery making the lights much brighter and removing the electrical load from the switch (while the switch no longer powers the headlights it will still function as your headlight switch.) Installation notes: The H4 wiring harness is truly plug-and-play. The only additional components I used were self-tapping screws, a piece of sandpaper for cleaning up the locations where I terminated my grounds, standard electrical tape, and a few extra cable ties. The overall length of the harness was plenty long for me. There wasn’t a whole lot of extra space to mount the relays next to the battery but it was doable. Had I simply taken 5 minutes to remove the battery it would have been a breeze. Total install time was about 90 minutes. Results: Noticeably brighter OEM headlights. Happy headlight switch and your vehicle will be ready for H4 aftermarket LED headlights (which you’re going to eventually do anyway right?) The harness itself comes with an in-line 30-amp breaker for your battery hookup and 2-80 amp relays. As an electrician by trade, I was impressed with the overall product quality. The crimps were strong and secure. The only thing that concerns me about this entire project would be the fact that the relays are not water-proof which may be an issue for the 4x4 crowd who would much prefer driving through a creek than over it. Final note: There are great install videos on YouTube if you are new to these things. Even for a novice DIY project, trust me, this is as simple and straightforward as the reviews indicate. Last comment, terminate your grounds correctly. Years of experience as a sparky, it’s not the harness that’s not working it’s because you didn’t land your grounds right.

This product is fantastic, great quality easy to install worked perfectly in my 1965 Mustang.

Needed this harness for a 92 Toyota Celica. It was an easy install but for this/my car you have to place the harness and all of its relays/fuses with thought as there is not much room (pop up headlights made it harder). It was also me as I did not want to take off the front bumper to run it under that. I ran it behind/near the radiator. With some careful placement of the wires/relays I was able to get it in place as not to interfere with the headlight when they closed. The issue was not length but more of the fuses/relays getting in the way (for my car). The two big fuses (?) where loose on mines, had to zip tie them so that they will not fall off randomly. Time will tell if the harness will corrode or malfunction, but so far so good. I did not do a test to see if the LED headlight was brighter with or without the harness (I used an adapter to switch the wires around to get it to work without the harness), so I am not sure if the claim of having this will give you better power for the headlight/H4 style bulbs.

As an owner of a 1995 Toyota Tacoma, I’ve experienced my fair share of electrical issues, particularly with the headlights. Over the years, I noticed my headlights weren’t as bright as they should be, and I was dealing with dim, flickering lights that weren’t just frustrating—they were also unsafe. After a lot of research, I decided to try the H4 Relay Harness Kit for my Tacoma, and it’s made a world of difference. Why I Chose This Kit The primary issue I faced with my truck’s headlights was the dreaded dual ground problem that many older vehicles, particularly Toyotas, tend to suffer from. This problem stems from the headlights drawing power directly from the stock wiring, which isn’t built to handle the higher current demand of modern, brighter bulbs. Over time, this can lead to dim lighting, flickering, or even failure of the headlight bulbs. The H4 Relay Harness Kit is designed to fix this issue by bypassing the stock wiring entirely, providing a direct, stronger power source from the battery to the headlights. I was looking for a solution that would not only improve the lighting but also prevent future electrical problems, and this kit seemed to be exactly what I needed. First Impressions When the kit arrived, I was impressed with how well it was packaged. The H6054 7x6 Polycarbonate Headlights were clear and seemed very durable. I was a little intimidated by the wiring aspect since I’m not the most mechanically inclined, but the instructions were straightforward, and I quickly realized I could handle the installation myself. The H4 relay harness itself is well-built, with high-quality wires and connectors that felt secure and sturdy. The dual ground fix was a major selling point, as it addressed the key issue that had been causing my problems in the first place. Installation Process The installation was a bit time-consuming but not overly complicated. After removing my old headlights and stock wiring, I followed the step-by-step instructions to install the relay harness. The most important part was making sure I correctly connected the dual ground wires, which can sometimes be tricky if you’re unfamiliar with automotive electrical systems. I’d recommend taking your time to ensure everything is properly connected. Once the wiring was complete, I attached the new headlights, which fit my 1995 Tacoma perfectly. The connectors clicked into place with no issues, and the entire process took me about two hours. The Results After installation, I couldn’t believe the difference. The lights were significantly brighter, and they stayed steady with no flickering. The true benefit, however, was the reliability. With the relay bypassing the stock wiring and providing direct power from the battery, my headlights now operate with consistent brightness without the strain on the original system. Driving at night is now a much safer experience. The improvement in visibility is noticeable, and I no longer worry about my headlights failing or dimming during a long drive. Why This Kit Works The key to why the H4 Relay Harness Kit is so effective lies in its design. By sending the current directly to the headlights from the battery, it bypasses the weak stock wiring, which often struggles with higher currents. This avoids the common dual ground problem that leads to voltage drops and dim lights in older vehicles. Additionally, the polycarbonate headlights are tough, resistant to road debris, and maintain their clarity over time. Paired with the relay harness, they deliver a significant upgrade over my old, aging headlights. Final Thoughts As someone who’s not an expert in car modifications but loves keeping my truck in good working condition, the H4 Relay Harness Kit was a fantastic choice. It solved a major electrical issue and improved my night driving experience. If you’re dealing with dim or flickering headlights, especially in older Toyotas like mine, this kit will solve your problem. Rating: 5/5 This kit delivered on every promise, and I’m thrilled with the results. Not only have I solved the dual ground problem, but I’ve also ensured that my headlights will continue to function reliably for the long haul. Highly recommend!

Installed in 1987 Jeep Cherokee XJ. Works great. Took about an hour to install due to tight spaces. I had the flickering/dead headlight problem- internet search told me it was the classic full-amperage headlight switch. I replaced the switch but also read about and wanted to use one of these kits to move the amps over to a relay to prevent it from getting all melty again, which after replacing the switch it was clear this was not the first time this issue happened on this vehicle. The switch wiring plug had already been replaced by the previous owner assumingly due to meltage. As some other reviews mentioned my only complaint is this harness could be about a foot longer in all directions. It was a very tight fit into the passenger headlight/battery area, but it did fit after 30 minutes of swearing or so. Lamp connectors are ceramic. 80amp! relays. 40amp fuse. Wiring is as big or bigger than stock and I plan to switch to led lights anyway once these old ones burn out. But yeah, for how cheap it is I am surprised it works as good as it does. I did make sure to check all the connections and wiggle all the wires to make sure they were snug in the little sockets. I am sure some folks get one that was loose at the factory but mine was fine all over. 10/10 Would recommend. Only had it working a day so will update in a few months with how its holding up.

Seems good..all connection's worked.. Took pics of high and low beams using stock harness and KASLIGHT harness. No real difference with stock sealed halogens, but a must have for older Toyota LED conversion. You can see the fuller pattern and sharper cutoffs running LEDs. Concerned about wire gauge with this harness and your high beam dash bulb not working after LED light install? Read on. This will make you LED lights shine bright in your Toyota but there is a good chance your high beam indicator on your dash won't light up. The dash bulb isn't burnt, there is just not enough load to trip the bulb light with the lower power draw of LEDs. Simple fix is to crimp some male spade connectors on a 6 Ohm resistor and plug in to the open high beam circuit plug connector this harness replaces. (Open Driver side headlight plug on my 90s Toyota pickup.) Or use a piggy bag connector on the high beam circuit wire on the old harness. Bingo. Dash light. Seems to be working just fine now. A Lot of fuss about the wire gauge being chincy. While there isn't as much copper in strand one would expect given the size of the wire (insulation is cheap, copper is expensive after all) this doesn't present a fire hazard. FALSE ALARM. For two reasons: 1) the amount of actual copper is about the same compared to the stock Toyota wiring on my rig. The Toyota wire gauge is about 16ga. 2) incandescent bulbs draw more power than LEDs so if you are using this to convert to LEDs you have an added safety margin. See photos for proof and the fact a load resistor must be used to trip high beam indicator bulb since the LEDs don't draw the same power as stock lights. Disclaimer, I am not an electrical engineer, however I do have a basic knowledge of electrical circuits, amp draw/loads and I know how to turn a wrench. Buy with confidence, and to the would-be alarmists, stay in your lane.

This harness proved necessary because Toyota switches grounds while present day diode headlights switch power. This harness handles the conversion. I had no issues with the quality of construction and installation was as easy as it could be expected to be in the tight engine compartment and front end of this sports car. The headlights work fine. There is an issue however, which is why I have removed stars from my rating. Specifically, the car no longer has a high-beam indicator and, when I turn on the fog lamps, I am getting high beams out of the headlight rather than low beams. The problem appears to be that the low-beam side of the Toyota harness is expected to float high with current from the low-beam side of the headlight when the headlights are on in high beam, and it is this float-high that drives the high beam indicator AND turns off the fog lights when high beams are on. This relay package is disconnecting that section of wire and it is now open - neither high nor low - when the high beams are on. I did not generate a schematic of the harness before installing it, and to generate one now would pretty much require me to remove it in order to do that. This, I would rather not do. The problem should be simple enough to fix, but I really need a schematic of the harness in order to fix it. If the vendor will provide the schematic, I will update the review and add stars.

Great product. Made my headlights brighter and was easy to install.

Necesario para instalar luces principales Led en vehículos antiguos con polaridad inversa como Toyota Pickup 86 4x4

Funciona muy bien, Quedó en mi Toyota 1983

Easy to install and allowed me to upgrade my lights

Excellent wire harness..I'm.very happy... I've ordered new led headlights from.ebsy. please note. One connection end is broken. The wires and connectors pulled out of ceramic base. Feels very cheaply made?