This circuit tester plugs into the four-way trailer connector on the vehicle. The bright LED lights analyze the trailer connections and indicate which functions (tail, left turn and stop, right turn and stop) are working properly and which are not.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hey everybody, Ryan here at etrailer. Today, we're going to be taking a look at the Curt four-pole vehicle side trailer, wiring tester. So, if you guys have ever towed a trailer before I'm sure you have encountered this problem. You get all hooked up, and kind of do a walk around, you know you kind of do a pre-trip before you hit the road. You check a few things out, one of them being the lights. And, of course, you turn your blinkers on.
Maybe you have a light out at the trailer. You hit the brakes or the tail lights and something's wrong. And then this kind of turns into a headache. You know, you're, you're checking your vehicle side, checking fuses, making sure everything's good there. Then, you get the going on the trailer side.
It's kind of just a big mess. And one thing you can do to isolate that problem is use a vehicle side tester like this. So, the way this is going to work, is it's going to plug into your vehicles four way flat connector. All right, and then that's going to isolate the problem. So, once you plug this in, you can run through all of your signals and your lighting functions.
And if they all work back here, then you know, okay something's going on with my trailer and you can focus your time on that. If you don't have all your functions back here chances are good. You could say, okay, trailer's probably okay. I probably have an issue with my vehicle side and you can focus your energy there. So, at the end of the day, if you do have an issue, it's a great little tool that can potentially save you a ton of energy.
So, whenever you are plugged in to your vehicle side, you can test the function. So we're going to have our left turn signal, our right turn signal, our taillights, and our brakes. So, since these lights are LEDs, really easy to see, even on a sunny day like today, which is convenient, especially if you're by yourself, kind of trying to, you know if you have miring stored inside you can hold it up or mount it up and check it while you're in the driver's seat, so you ain't got to get out of the car every time. But, since we don't have any labels or anything here, I figured it'd be useful to share what lighting function illuminates the light on the test, or if that makes sense. So, this light here should turn on when you use your right turn signal, the one next to it should turn on when you use your left turn signal, both of these lights should illuminate when you apply the brakes, and this one should come on whenever you have on your tail lights. So, let's say if you're, you know, testing your, your right turn signal, this one should be flashing. See, this one isn't, but this one is, okay So, you're still getting something to happen, but on the wrong circuit. So, that could help kind of direct you as well to get it figured out. You may have a short or something like that in the electrical system, and that could be looked at. So, when it comes to this tester, honestly, this is probably the last one you'll ever need, unless you lose it or something like that. Things are actually pretty, pretty stout. They're pretty solid. These are actually the exact ones we use here at the shop. And we use them day in and day out, all the time, and we've had them for years. They still work like they should every day and they really take a beating, and they just continue to work. So, for the average person to use them, occasionally, I mean this should last for the life of your vehicle or the life of your trailer, and then some. So, really nice, you know, it does have a key ring holder on the top there. And what we do, here at the shop, is usually put a zip tie or some type of key chain on there just to make a little larger so we can hang it up. If I had, you know, if I was going to keep one in my personal vehicle, something like that, you know, I'd probably end up using a key chain with my trailer lock and everything else on it, throw it in the glove box, so you always have it. So, it's a little nice touch and something I thought was worth mentioning. So, as I mentioned, this could work for your four way flat type connectors and it just plugs right in, just how you'd plug into the trailer side. And if you have multiple vehicles or different trailers, things like that and you need a different type of tester, not a big deal. We offer other ones as well. Whether you have a five way or a round seven-pole something like that. There's going to be a tester similar to this available here. That way you can use it for that wiring as well. And that'll finish up our look at of the Curt four way flat trailer, wiring tester..
Average Customer Rating: 4.8 out of 5 stars (1681 Customer Reviews)
Made it easy to test that my wiring harness was installed properly. Worked perfectly. The only reason I didn't give it five stars is because there were no instructions to explain what each LED means on the tester. I just plugged it in and made sure something lit up when I used my turn signals, brakes, and headlights.
Handy had to check brother’s car harness also. Used the old connector cover on the pins just turn it around.
Works great for testing your lights on your vehicle before hooking up your trailer.
Only took me an hour to install on my 2023 telluride by myself! I didn’t jack the car up, it was a little bit tight but was able to get under it with a creeper. I used the spare tire (donut) to support the exhaust, so no need to tie it up. Mine had a heat shield over the muffler which made it difficult to get a socket on but was able to work one on without removing the shield. I used a jack stand to support one side of the hitch while getting a bolt in the other side to hold it. I used a multi tool to notch out the plastic on the bumper. Check the other comments for the measurement, not sure what the instructions say but comments say they are wrong???
Overall a very smooth install without any major surprises!!
works exactly as intended/described. Great way to double check my trailer wiring harness installation before putting everything back together again.
Super easy to install! Instead of reading the paper installation instructions, I played and paused the eTrailer installation video at each step!! The videos from eTrailer are super helpful!!!
Just what I needed, worked great with new Hopkins Dual Connector on my 2019 Colorado
A must have if you are pulling a trailer. Sure, you can plug your electrical line into your trailer to ensure everything is operating properly, but it's nice to have a simple tool to help diagnosis a problem if you have one.
The Curt LED 4-Way Flat Connector Tester was a very easy way for me to confirm that I correctly installed the wiring harness that I purchased.
Inexpensive way to make sure the wiring was done correctly BEFORE I went to pick up the trailer...
Good tool to have. Much easier than a voltmeter or test light!
Just the right gadget when working on trailer lighting systems.
Excellent product choices, reasonable pricing, and great communication.
I would buy again from eTrailer!
Bought this tester to get to the free shipping threshold as I recall, but no matter, this is THE fast and easy way to test the vehicle side of your trailer harness. I use it before every tow. This way if there’s an issue I know it must be with the trailer wiring. Small price to pay to save what’s left of my sanity lol.
Handy little tool to have on hand to verify your wiring. Quick and painless testing for wiring up a 4 pin connector. Did require a 2nd pair of hands to hold it up while I tested all the lights and functions.
A handy, simple tester worth the price. Small size makes it easy to keep in car by the end of the wiring harness.
Awesome product. Installed hitch and wiring today, and was able to test the plug points with this. Made it easy to test without having to hook up anything.
I have not encountered any issues or quality concerns with this product thus far. Product quality is good for price point.
This wiring tester is very useful and the price very reasonable.
This thing is cool. I saw it on one of the etrailer Subaru videos. Figured why not. It’s $10 for solid peace of mind. Plugged it in. Tested the lights. All is well. Thanks!
This tester helped with testing my install, also use it to make sure my harness is correct.
This is a nice little tool for making sure the harness works, before you button up your interior panels.
Does what it says. It shows what the trailer should show without connecting it up. It’s worth it.
So great to have the piece of mind that all your electrics are working as they should before you load up to tow. For this price, definitely worth having kicking about in the trunk.
Picking up a trailer in another state and need to check my new installation beforehand. It work's, now I'm ready for trip and safely bring my trailer back.
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