True MODS 4-Way Flat Trailer Light Tester 4-Pin Wiring Circuit Test

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.

Love it and use it on my truck and Jeep to make sure all the lights are working. Had one light out and picked up on a bad wire quickly. Good quality also. Highly recommend

This device works well. Currently have it inside the cab of my van so I can see which rear lights are activating.

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.

Helped me figure out my car fuse was the problem. I was ready to re-wire my trailer as the running lights were not working. Turns out it was the vehicle. For the price it is worth it and I recommend for anyone that has a trailer to get it to help save you time and sanity.

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

Used it to check the wiring on my 97 Tacoma. Did have a problem, which turned out to be dirt in the truck plug.