True Mods 4-Way Flat Trailer Wiring Tester [Nickel-Plated Copper Terminals] [Male & Female] [Continuity Test] 4-Pin Trailer Light Wire Circuit Tester

The True Mods 4-Way Flat Trailer Wiring Tester is not just a useful tool—it is an absolutely essential piece of equipment for any trailer owner. This compact, clever unit completely changes the way you troubleshoot trailer lighting issues, making what is usually a frustrating process quick and straightforward. The Problem Solver The biggest pain point with trailer wiring is having to constantly hook up and unhook your tow vehicle just to see if a light is working. This tester eliminates that hassle entirely. This unit allows you to diagnose your entire lighting system without ever connecting the trailer to your car or truck. All you need is a simple 12-volt battery and a couple of wires to power the tester. Once connected, you can perform comprehensive checks on: Running Lights Brake Lights Turn Signals (Flashers) Emergency Blinkers Operation and Effectiveness The design is simple and highly effective. By providing power directly to the trailer plug through the tester, you can isolate and test each circuit individually. I was personally able to diagnose and repair my trailer lights quickly thanks to this invaluable tool. Instead of playing the frustrating "guess-and-check" game with the vehicle, I could pinpoint exactly which wire or connection was faulty on the trailer itself. This not only saved me considerable time but also prevented wear and tear on my vehicle's electrical system. Final Verdict If you own a trailer of any kind, the True Mods 4-Way Flat Trailer Wiring Tester is a must-have addition to your toolbox. It is a small investment that pays massive dividends in time and frustration saved. Its ability to turn a complicated diagnostic task into a simple bench test is brilliant. Rating: 5 out of 5 Stars. This tool is a true game-changer for trailer maintenance.

Does exactly what it says. Easy to read. Bright lamps. Has saved me a LOT of time troubleshooting trailers wiring. Recommended.

This 4-Way Flat Trailer Wiring Tester was exactly what I needed to troubleshoot a wiring issue on my Dodge truck. The LED lights are bright and clearly labeled, making it really easy to see which functions (turn signals, brake lights, etc.) were working properly. It plugged right into the trailer connector with no hassle and helped me diagnose the problem in just a few minutes. Solid little tool—simple, effective, and a real time-saver. Definitely a must-have if you tow or work on trailer wiring regularly.

Works well and is good to have with you. You can verify if your trailer is getting power and if it is going to the correct blinker side.

just installed a hitch and utilized a wiring harness kit for the lighting. I got this so I could test the trailer wiring hook ups. worked fine. I had actually bought one before but had lost it and used it on a few other installs. it's inexpensive, easy to use and serves its purpose by letting you know all the lights/wiring will work correctly.

I chose a different brand first because it used colored LEDs, mistake. The other brand was spurious and I had to return it. This one has all red LEDs but they are super bright, and after trying both I actually found that the multi-colored ones were more distracting. I like these better, and they work great. I like the pass-through design, I leave it plugged into my cars wiring all the time and it has its own dust cover when the trailer isn't plugged in.

A1 seller good item

Works just like it claims, does what it’s supposed too.

Très efficace pour trouver un problème de connection. En moins d’une minute tout était réglé.

Worked as described

The fact that it works if a trailer is plugged in or not

I tried this item and none the lights lit up. I checked and followed the instructions and nothing lit up.

When I plug it in to the truck and trailer the lights are upside down so it's kind of hard to see but still works.