CURT 57004 LED-Compatible 7-Way RV Blade Vehicle-Side to 4-Way Flat Trailer-Side Trailer Wiring Adapter , Black

I replaced the original incandescent lights on my boat trailer with LED lights. I had all kinds of weird malfunctions on the trailer lights. Different things every I hooked the trailer up. From research, I found out that the computers in older vehicles that do not have LED lights do not detect the LEDs very well due to them having a much lower resistance than the incandescent bulbs. This item solved the problem of towing with my 1998 pickup by adding resisters in the light circuits.

This is what you need for 2024 2500 HD. Works perfectly.

I originally bought https://www.amazon.com/Oyviny-Trailer-Adapter-Connector-Waterproof/dp/B08MDW63DH for a 2021 Audi Q7, but it triggered a warning light on the dash for a faulty trailer light (even though all lights worked).After doing a little more research, I returned it and tried this Curt model instead. While it cost 2x as much, it has the features needed to work on cars like Audis.

This adapter works perfectly on my 2004 VW Touareg with the factory tow package. Before, the dash would chime every minute or two and warn that the trailer lights were not working, even though they were. Now, they not only work perfectly but the computer doesn’t complain about bad bulbs.

I bought a light bar that was wired for a 4 pin connector and a single wire for reverse. The light bar manufacturer stated that new GM truck owners would have to splice the wires to make it work. This is a no-go. An install video on Youtube mentioned a CURT 55384 would work (he had a different OEM truck). The 55384 however did not allow the truck trailer lighting control module to register enough resistance to allow the truck to power the 7 and 4 pin outlets. However I was referred to the Curt 57004 as a work around and it worked perfect! If you have a GM truck that wont register your LED lights on a accessory bar or your trailer, this is a perfect way to make it work.

I have a LED light bar on my bike carrier, and it worked flawlessly with my old car which had an aftermarket trailer hitch and wiring harness. New car has a factory-installed tow package and the light bar stopped working, not because it's LED (I tested LED trailer lights on the new car and they work) but because its internal circuitry (it runs brake lights and turn signals separately, with a regular 4-pin connector) was interfering with the car's trailer-sensing circuitry. This adapter has built-in resistors and brilliantly solved the problem.UPDATE: the old light bar broke and the replacement (same identical model) does NOT work with this adapter, The turn signals and tail lights work, but the brake light keeps flickering/flashing. No idea why, I guess it's a delicate balance of voltages and currents and the two "smart" circuits (the car and the light bar) are just not compatible. Too bad as I really liked the light bar...

No issues. Does what it's supposed to do. I have a custom trailer hitch that lights up as I drive. 2019 F-150

OLD REVIEW: This solved my problem with constant error messages. However, there is still a nuisance issue. It's not an issue with this product, but rather, with the truck. I have lighted trailer hitch covers. Unfortunately, the stupid computer in the truck thinks a trailer is attached and every time I start and restart the vehicle, I have to go through six button presses to exit the trailer setup screen return to my default speedometer screen. So whenever I use a lighted trailer hitch cover, I am set up as using the "default trailer."I hate all modern computers and electronics that try to do all the thinking for you and always get it wrong, or try to force you into settings you do not want. I would like to do my own damned thinking, thank you very much!!! Whew. Been wanting to get that out for a long time now.But as I said, that is not an issue with this product. Just something to be aware of if you buy this. You will have to go through the nuisance menus every time you start the vehicle.NEW REVIEW: Well, I spoke too soon. After checking out all the functions of my LED lighted trailer hitch cover, the turn signals DO NOT WORK. I get running lights and brake lights, but no turn signals.So, I went from five stars to one star.I don't have my LED trailer lights installed yet, so am concerned whether it will work correctly. I may be back for a third review. Stay tuned...If someone from the manufacturer reads these reviews, perhaps you can explain why my turn signals don't work with your adapter??? And don't try to blame my wiring. The old incandescent bulbs work fine. And my LED lighted cover works fine without your adapter, that is, until the truck's computer decides to "do it's thing."

This worked perfect on my 2024 model y. Had the hitch installed at dealer and LED lights on trailer work with this.

IT IS PERFECT TO MY ML 350 .

2019 silverado high country. New trailer with LED lighting. Truck wouldn't recognize the trailer due to the low draw LED lights. Dealer wanted $150 to 'diagnose' the issue. For $20 this fixed the issue.

I couldn’t get my led lights on my sled deck to work. This adapter worked!

Nothing wrong with it per se but not what I thought I was getting from the poor information on Amazon.