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Curt LED 4-Way Flat Connector (Vehicle End) Tester

Curt LED 4-Way Flat Connector (Vehicle End) Tester

Item # I26
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Lowest Prices for the best wiring from Curt. Curt LED 4-Way Flat Connector (Vehicle End) Tester part number I26 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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Curt Wiring - I26

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Curt LED 4-Way Flat Connector Tester

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.

I-26 Curt LED 4-Way Flat Connector Circuit Tester



58260 Curt LED 4-Way Flat Connector (Vehicle End) Tester





Video of Curt LED 4-Way Flat Connector (Vehicle End) Tester

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Curt Wiring - Tools for Wiring - I26 Review

Speaker 1: Today, we're taking a look at the CURT LED 4-Way Flat Connector Tester for the vehicle end. This small compact circuit tester plugs into the four-way trailer connector on your vehicle. It has the bright LED lights that analyze the trailer connections and indicate which functions are working properly and which are not. That way, you can take care of the problem. The LEDs have a protective casing over them to ensure that they don't get damaged. When you plug this in, this LED light right here will light up for the taillights.

This one right here is for the left turn and this one is for the right turn. Then when you apply the brakes, both the left turn and the right turn LEDs will light up. That's if everything is working as it should.Now, the housing is made from a durable plastic construction, does have the little holder here so you could put it directly on a key chain or you could hang it on a nail in your shop or garage. Terminals are corrosion resistant and it does have a nice easy grip design, so that way you can easily grab on to it and makes for simple connecting and disconnecting. That's going to do it for today's look at the CURT LED 4-Way Flat Connector Tester for the vehicle end..


Customer Reviews

Curt LED 4-Way Flat Connector (Vehicle End) Tester - I26

Average Customer Rating:  4.9 out of 5 stars   (563 Customer Reviews)


- I26
by:

Another great product from Etrailer.com Do yourself a favor, buy one of these to keep handy in your glovebox. They work great. 703362



- I26
by:

I had placed an order from etrailer for a trailer wiring kit, as I'm going to be renting a uhaul trailer to move some stuff. The wiring kit looked fairly easy to install (based on a video on etrailer), but it then occurred to me that I wouldn't know if I installed it correctly until I picked up the rental trailer, and then it would be too late to do anything about it. So I looked at various testing tools and this looked like the easiest (and cheapest). It worked exactly as promised. (Turned out I installed the wiring kit correctly.) My only suggestion is that there should be a tag (or label, etc) on the tester indicating what light should light up for what function. I know the etrailer website shows which light is for which function (ie brakes, lights, turn signals), but it would make sense to enclose this info with the device. That said, this was easy to use and did exactly what it should. 141483


Comments
The wiring kit I bought continues to work just fine. Im also glad to have purchased the small wiring tester at the time - the first time I rented a trailer the lights werent working without the tester, I would have assumed the problem had to do with the installation of the new wiring, but this gave me the confidence to know the problem was with the rented trailer and I could insist they come and fix it which they did.Anyway, still very pleased with the purchase, and would continue to recommend it.
BJB - 07/20/2015

13497

- I26
by:

Works as expected 567965



- I26
by:

I got this as an inexpensive add on to check out the installation. It did that fine but the unexpected need came in several months later when a trailer light would not work. I pulled out the tester and confirmed the circuit was working which resulted in me finding a burnt out bulb in the trailer. It just made tracing the problem easier and confirmed the vehicle wiring was good. 695587



- I26
by:

After wiring up the harness this tester shows various lights when brakes, running lights and turn signals are activated. The only problem is that the lights are not labeled so you don't know what light circuit is being activated. With the harness I wired there was no way to wire it wrong ( just plug n play) so it should be correct. Have to wait until trailer is attached to be sure. 617603


Comments
The tester has one socket and three pins. The pin closest to the socket is the Running Lamp circuit, next is the Left TurnBrake Lamp circuit and last is the Right TurnBrake Lamp circuit.
-- Mike L - 04/06/2019

51537

- I26
by:

Works great. Beats heck out of hooking up a trailer just to see if you have everything wired right. For the price, I think everyone should have one. Thanks. 418938


Comments
This may have been a one-time use piece of equipment. Not too sure when I might wire another vehicle for a trailer. But It is WORTH EVERY PENNY!
Harry M - 08/18/2018

42527

- I26
by:

This works great the same as everything I have ever gotten from etrailer. This place is my go to place 852503



- I26
by:

Worked great to test the new harness before going to pick up the trailer- pretty basic but quite functional. 851062



- I26
by:

Worked as advertised. 850764



- I26
by:

Great little tester that rides neatly in the glove box. 850405



- I26
by:

Great service, arrived on time and everything fit perfect. Etrailer came through again. Thank you. 853258



- I26
by:

Work perfect, its the utem i was needed .. Thanks 848368



- I26
by:

Great addition for regular checking... 845940



- I26
by:

This is a great little tester: all it's lacking is a small card or sticker telling you what the LED lights mean. (Tail/Running lights, left blinker/brake, right blinker/brake--although I might have the left and right mixed up.) 845513



- I26
by:

Work great easy use and very handy when trailer is not around! 840096



- I26
by:

Pretty painless install, I was able to do it with out extra hands, with the rear of the car up on ramps. If installing on a CRV, removing the exhaust hanger in front of the rear wheels made this go much more smoothly. 848934



- I26
by:

OK, this one does the job. There is nothing wrong with it. I was going to take a star away, but then decided not to because my complaint only warrants at most taking away a half-star. Here's why: I think the lights are on the wrong side. If you are using this with a 4pin/7pin connector like part HM40975, then the lights are facing inside (the cover of the 4pin/7pin connector fold over and partially cover the lights) - so you have bend over and open up the door cover to peek in to take a look at what lights are lit up. If the lights were on the other side, it would much better accommodate testing a 4pin/7pin connector. I didn't think that warranted losing a star though - I guess I would have preferred to give it a 4.5 stars out of 5 if I could have. 831299



- I26
by:

Tested my new harness. Works great 831277



- I26
by:

NICE PRODUCT SO YOU CAN TEST LIGHTS BEFORE HOOKING UP TRAILER TO MAKE SURE EVERYTHING IS GOOD 830890



- I26
by:

A simple and cheap way to make sure your trailer lights are working properly. 830198



- I26
by:

1Excellent addition to my tool kit! 828990



- I26
by:

One of the best shopping experiences on the web. Great service and communication. Easy to follow directions and love the [installation] tutorials. Thank you! 831011



- I26
by:

Does what it says, and sure beats having to use the trailer as a test rig. Get one of these for each tow vehicle and just keep it in the glove box. 828120



- I26
by:

Much better then using a light tester. 827545



- I26
by:

Smart choice to make sure You did it Ri ght 825616


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Ask the Experts about this Curt Wiring

  • Troubleshooting Vehicle-Side Trailer Connector Right Turn Signal Staying On
    If you are putting a test light like the Curt # I26 on your vehicle-side 4-Way then you may have installed your vehicle-side 4-Way incorrectly. Is your running light indicator blinking when you put your right turn signal on? If this is the case then you simply need to swap out the wires for your right hand and running lights (see attached photo). Another possibility is that you have a bad ground or your vehicle connector is full of corrosion. Check both of these while you are at it and...
    view full answer...
  • What are the Different Circuits on a 4-Way
    The jacketed circuit is the ground. The one right next to that one is the tail light circuit, next to that one is the left turn circuit. And then the last one on the end is the right turn circuit. Check out the picture I attached to see the circuits labeled. I attached an FAQ article on trailer wiring that you might find informative also.
    view full answer...
  • Can Curt LED 4-Way Flat Connector # I26 be Left on Vehicle Indefinetely
    Leaving the Curt LED 4-Way Flat Connector # I26 plugged into a 4-way for an extended period of time would not be an issue at all. Since you used dielectric grease like the part # 11755 you wouldn't have to worry about corrosion either.
    view full answer...
  • What are the Functions of the Lights for Trailer Wiring 4 Pole Flat LED Tester # I26
    From left to right the first light tests running lights, the middle light tests left turn and brake lights, and the last light tests right turn and brake lights. On a 4-Way flat vehicle connector, the one exposed pin is the ground, next to that is running lights, then left turn and brake, and the last pin is right turn and brake.
    view full answer...
  • Is There a Way to Trick Parktronic Sensors on a 2016 Mercedes-Benz Sprinter for a Bike Rack
    I am not sure if this will have enough draw but we have testers like the Curt LED Tester # I26 which puts a small load on a 4-Way Flat connector. This is used to make sure that your wiring is working correctly but it may be enough to trick your sensors. If you have a 7-Way then I recommend using the Tow Ready # 20142 as it will simulate a draw as well. Please note that both of these products are designed to be plugged in for short periods of time and haven't been tested for prolonged...
    view full answer...
  • Turn Signal Shows Hot all the Time with Plug-In Trailer Connector Tester
    If a 4-way trailer connector tester like part # I26 shows that the drivers side turn signal on the Curt T-Connector Vehicle Wiring Harness part # C56344 for your 2014 Jeep Compass is constantly hot then you would first want to remove the driver's side tail light assembly. Once this is done you would then need to remove the connector to the harness and inspect the pins making sure none of them are bent and or corroded. If they are then you will need to clean them up with some electrical...
    view full answer...
  • Why Would Circuits of the I26 Partially Glow When No Trailer Wiring Circuits are Activated
    It sounds like your trailer wiring setup is fine. The thing about LEDs (like what the # I26 has), is that they require such a tiny amount of amperage to partially illuminate that when they are used in trailer wiring situations they can partially glow like you described if there is any amperage at all bleeding out of the circuit. What I would do is connect the 4-way of your 2014 Ford Explorer up to a trailer and see if it functions properly. If it checks out then you would be good to go.
    view full answer...
  • Fuse Blows on 4-Way Harness When Using Circuit Tester 2013 Jeep Compass
    It sounds like the 4-way tester you are using like part # I26 has a short somewhere which is in turn causing the 10 amp fuse on the Curt T-Connector Vehicle Wiring Harness part # C56344 for your 2013 Jeep Compass to blow. What I recommend doing is testing each circuit with a standard test light like part # 40376 to check for function. If all is good then you know the problem was in the 4-way tester you are using. All of the converter boxes used in Curt's wiring harnesses are tested...
    view full answer...
  • Which Lights will Illuminate on the Tester # I26 When Brakes are Applied
    When your brake lights are pressed and you are using the # I26 as a tester the two pins opposite of the jacketed (ground) pin will illuminate. These are the left and right turn/brake light circuits.
    view full answer...
  • Comprehensive Vehicle Side Trailer Connector and Wiring Tester
    Most of the vehicle end trailer connectors we have will test for voltage on the circuits. If there was a short to ground then all of the lights would light up on the tester and you would know there is a problem. We do have a comprehensive trailer side tester, # 8010, which goes much further than any of the regular testers like # I26. But it is not designed for the vehicle side. For the vehicle side we have # HM50918 that can test multiple connector types on a vehicle (4-Flat, 6-Way round,...
    view full answer...
  • Recommended Trailer Wiring For 2020 Jeep Grand Cherokee Without Tow Package
    For your 2020 Jeep Grand Cherokee I recommend the Tekonsha T-One Vehicle Wiring Harness part # 118727. It's custom made for your Jeep and it gives you a 4 way flat trailer connector so you have all the lights to tow a trailer safely and legally. It gives you your tail light functions, turn signals, and brake lights. The wiring installs behind your tail lights and plugs inline between the factory connector and the light assembly. There is no cutting or splicing of the factory wires, however...
    view full answer...
  • Recommended Trailer Wiring Harness for 2020 Toyota RAV4 Hybrid
    The trailer wiring harness I recommend for your 2020 Toyota RAV4 Hybrid is the Tekonsha Kit part # 118801. It provides you with a 4 flat trailer connector, and has a plug in design; so it does not require any cutting or splicing. I also like the kit because the converter box in the kit has a reputation for being very reliable and has a higher amperage rating than similar wiring kits.The wiring kit installs behind the trim panels in the rear hatch on each side, where you can mount the converter...
    view full answer...
  • Is Dealer Activation Required for Trailer Wiring Harness # C55384 on 2015 Jeep Grand Cherokee
    When you install the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector # C55384, it may be necessary to see a local Jeep dealer to activate the tow package wiring circuit. Some vehicles have the active tow package wiring and others do not, so you will know as soon as it is installed if this is required or not. If you test the function using a tester like # I26, a circuit tester like # PTW2993, or connect it to a trailer, you will be able to...
    view full answer...
  • Right Turn Signal Always Has Power When Testing 4-Way with Circuit Tester
    It sounds like you have a classic ground issue with the Curt T-Connector Vehicle Wiring Harness part # C56277. When testing the 4-Way with a tester like Curt LED 4-Way Flat Connector (Vehicle End) Tester part # I26 the right turn like should only light up when you activate the right turn function. If it is always illuminated like you mentioned, I recommend to make sure the ground wire of the harness is attached to a clean bare metal surface on the frame. If you don't have a proper ground...
    view full answer...
  • How to Wire LED Replacement Trailer Lights
    If you are looking at and LED Trailer Tail Light like part # STL8RB, then you will not need a converter to make it compatible with the 4-Way Wiring Harness on your truck. You will need to figure out the wiring on your trailer to make sure that you get all of the wiring done correctly. You can use a Circuit Tester # I26 for that purpose. All you have to do is hook up your new LED lights using the following information. Brown is for tail lights Green is for stop and turn White is...
    view full answer...
  • Taillights and Turn Signals Working But No Brake Lights on Trailer
    Almost every trailer in the U.S. uses a 2-wire or combined wire tail light setup. This means that the turn signals and brake lights are on the same circuit and use the same bulb in the trailer tail light assembly. Because of this, virtually every trailer wiring adapter is designed to carry the turn signal and brake lights on the same pin circuit, so I would assume that this is the case for your 7 to 4 way adapter. It sounds like with working turn signals and taillights, that the problem...
    view full answer...
  • No Function on any Right Side Lights on Trailer Behind 2010 Subaru Forester
    I have found the best way to find a bug in an electrical system is by process of elimination. Eliminating possible sources will eventually lead to the right spot. First thing I would do, is check the 4-Way connector on your Subaru Forester. Using a circuit tester like part # 40376 or a 4-Way tester like part # F5CT or part # I26. The white wire is ground, the yellow wire is left turn and brake, the green wire is right turn and brake, and the brown wire is tail lights. Chances are, the...
    view full answer...
  • Trailer Hitch and Wiring Recommendation for 2014 Toyota RAV4
    For a trailer hitch for your 2014 Toyota RAV4 we have the Draw Tite hitch part # 75235 that you referenced which is a confirmed fit and would work well. This would have been what I would have recommended you since it has the best capacities and price so you are on the right track. Then for trailer wiring the Tekonsha kit part # 118578 that you referenced is the best choice as it is the most reliable option we offer too so it's the way to go. To test this 4-way we have the # I26 that...
    view full answer...
  • Recommendation on a Trailer Light Tester
    I found a solution for you. The Tow Ready 7-Way Trailer Vehicle Tester, # TR20117, will allow you to test the lighting functions on your vehicle's 7-way trailer connector. The plug connects and used LED lights that will display if you have a properly functioning 7-way or if there is an issue with the vehicles signal output at the connector. Also, if you are needing to test a 4-way flat connecter, I recommend the Curt LED 4-Way Tester, # I26.
    view full answer...
  • 4 and 5 Pole Trailer End Connectors
    We have trailer end connectors in both 4 and 5 pole configurations. Also, we do carry covers that can be added to 4 pole connectors and boxes that can be mounted on the trailer to store connectors in. We also have circuit testers that can be put in line with the vehicle and trailer or just plugged into the vehicle. The 5 way circuit tester, 20115, is an in-line model and should work for both 4 and 5 pole connectors. I have posted links below for your convenience.
    view full answer...
  • Vehicle Side 4-Way Trailer Connector Plug-in Circuit Tester Lights Light Up when Connected
    If the lights on a 4-Way trailer connector tester such as # I26 light up when connected that means that those circuits are receiving power. It doesn't take much power to light up these small LED lights so even residual current could set them off. This is typically more likely on aftermarket installed trailer wiring harnesses that have a connection to the battery to power the trailer lights. It could also indicate a short circuit if the lights stay on all the time. The likely cause is...
    view full answer...
  • Malfunction Turn Signal Light on Sunline Travel Trailer
    The first step would be to check the wiring from the malfunctioning light all the way up to the connector. Make sure all the connections are reasonably clean and secure, and check for frayed wires. If everything looks good from there, I would begin to look at the tow vehicle wiring. Check to make sure your connections are clean and secure. We have a few handy devices that could help you check all this. You could use a circuit tester like part # 40376 to check to see what connections...
    view full answer...
  • No Trailer Lights on a 2018 Honda Pilot with Tekonsha 7-Way Harness Part # 118760
    What type of tester are you using? If it is one like the Curt LED 4-Way Flat Connector part # I26 then that may be part of the problem as these are not foolproof and do not always work with all wiring harnesses. Therefore, I would check each of the pins with an actual circuit tester while the respective signals are active. These are much more accurate than the above testers. In regards to the T-One Vehicle Wiring Harness part # 118760 which is a fit for your 2018 Honda Pilot, there...
    view full answer...
  • Troubleshooting Trailer Running/Parking Lights Not Working on Truck Wiring Harness
    From the sounds of it, you have a truck issue. Since you have used a multimeter like # BTMT15 as well as a lighted tester like # I26 or # TR20117, it does sound like you aren't getting that running light power. This is often a separate circuit in trucks, so you will want to check your owners manual for fuses or relays that state trailer running lights or parking lights. Fuses don't always look bad so you will want to use your meter to check for power on both sides of fuses and then...
    view full answer...
  • Will Wiring Harness # 118534 Work with Power Lead Disconnected or Damaged?
    The T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118534 will not function without the power lead. It may function with a slightly damaged power lead, so I recommend using a tester like # I26 to test your wiring functions and simply visually inspect your power wire to your battery.
    view full answer...
  • Testing the Hopkins 4-Way Connector Not Showing Power on a 2009 Chevrolet Equinox
    You can test the Hopkins # HM11141265 by using a circuit tester like part # I26 while you have a helper activate the various light functions on your 2009 Chevrolet Equinox to make sure that the correct signals are coming through. If they aren't then you have some bad wiring on your Equinox (granted you installed the fuses and relays and they are okay). If you do get signals then you have a wiring issue on your trailer. This can be traced back to a faulty ground or damaged wiring. Make...
    view full answer...




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Info for this part was:

Test Fit:
Joe V
Video by:
Andrew K
Expert Research:
Jameson C
Installed by:
Cole B
Video Edited:
Chris R
Updated by:
Kristina F
Updated by:
Isabelle B

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