4-Headlight Relay Wiring Harness H4 Headlamp Light Bulb

This was a retrofit for a 4th Gen firebird, using h1 and 9005 projectors. Plugs didn't matter since I would be changing them anyway. The wiring actually feels decent, no idea if it's OFC or AL clad. the relays seem decent. I ran a 3A diode on pins 87 to keep my low beams at the same time as my projector high beams, works great so far.

High and low beam OEM harness side was flip flopped. I quickly swap the pins around and it worked! I am happy with the purchase. It took 60 minutes to install and I had to temporarily remove both batteries.Squarebody1984 k30 crew cab dually 454

This harness enables your headlights to run directly off the battery. The harness just plugs into your existing headlight socket so your headlight switch still operates the headlights. The new harness has two wires that go to the battery and four ground wires, very simple. Take a picture of your headlights before and after, you will be amazed at the difference.

Harness is great so far, but time will tell. I installed this yesterday on 1962 Ford Thunderbird. A little surprised it came with zero instructions, but did a quick You Tube search for a tutorial for installation. I had installed halogen receptacles & bulbs for 4 headlights, but had some trouble with lights going off while on bright. Realized I needed this relay so increased amps would not be going through headlight switch & dimmer switch on floor. After installation I realized it had probably damaged $9 dimmer switch on floor, so replaced that too. So far headlight switch is working normally.

I would not recommend this product. I ordered it for my 71 GMC. Pictures look good but it feels very thin. I went ahead and installed it and got bright lights all the time. I traced down the instructions and it was installed as they showed. I removed it from the truck and was studying it and realized that one of the plugs is wired wrong from the manufacturer. I’m not reinstalling it. If it shipped from the factory with a Tested good sticker on it and it’s actually wired wrong, I don’t think I can trust the quality.

This worked great on our bus rewire.

It does what it says. Couple things could make it better. Had to change the pin outs on three plugs to get it to work correctly. It would be helpful to have a diagram in the instructions for how the plugs are wired to check against factory. Also the power lead could be longer.

Works as should now I just need to install my leds headlights. Took the flicker away from running off the alternator.