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Trailer Light Tester, 7-Way Trailer Plug Testerwith Red LED, Testerfor Diagnosing and Fixing Trailer Socket Circuit Problems

4.6 (8) Write Review
Free shipping on orders over $29.99

$13.99

$ 6 .99 $6.99

In Stock

About this item

  • Detection function: GRZWAYS trailer connector tester can quickly help you correctly determine the electrical functions of the vehicle and trailer, and can help you diagnose and repair trailer socket circuit problems in a short period of time.
  • Simple design: Plug and play design, simply insert the 7-way trailer plug tester into the connector, turn on the vehicle lights and signals, and then observe the LED lights on the tester. Each LED light has a clear label that can tell you which towing vehicle lights are working or not working. No need for other tools or batteries, simple and easy to use.
  • Durable and sturdy: The plastic body has excellent corrosion resistance, UV protection, and impact resistance, and can be used for a long time. Nickel plated copper test pins have the advantages of strong conductivity, wear resistance, and corrosion resistance.
  • Multi purpose: This tester is used to test tail lights, brake controller output, reverse or reverse circuit center pole, right turn/brake, left turn/brake, and 12 volt power supply. Test the functionality of 6 independent trailer lights.
  • Wide adaptability and practical design: small size, easy to carry, can be stored in glove boxes or toolboxes, without occupying extra space. It is suitable for almost all common 7-way trailer plugs, used for most SUVs, trucks, boats, trailer campers, caravans, food trucks, and other trailers. In addition, the 7-pin trailer plug tester comes with a 1-year warranty. Both are very practical for drivers.


LED indicator for circuit continuity tests. Features 6 LEDs, testing circuit for the tail lights, brake lights, reserve lights, left turn signal, right turn signal and auxiliary power. Made to provide excellent impact resistance and corrosion resistance for long-lasting performance. Compatible with standard 7-way blade trailer sockets. Small size for easy carrying, this trailer light tester can be stored in a glove box or tool box, no spare space need to be taken up. Function Codes BU: back up or auxiliary RT: right turn/brake T/M: taillights LT: left turn/brake BK: Brake controller output 12V: 12-volt power feed


Tammie Chancey
Reviewed in the United States on May 3, 2025
Worked great!
Chad C
Reviewed in the United States on March 14, 2025
If you've had many trailers or campers, you probably know it's not uncommon to have lights just stop working. This is a neat little tool that quickly helps you determine if it is the fault of the trailer lights, or the truck/SUV wiring that is at fault.I am happy with this product, especially for the price. The only reason I am deducting 1 star is because the 2 letter labeling is not very intuitive and it doesn't even come with instructions that let you know what these stand for. The listing does have an image that explains this better, but you shouldn't have to refer back to a product listing to make sense of all the 2 letter abbreviations.
Anonymous
Reviewed in the United States on February 19, 2025
The media could not be loaded.
Danny
Reviewed in the United States on February 1, 2025
We own a bunch of trailers that we work on throughout the year. The first step in diagnosis for us is making sure the vehicle plug is working properly. This make pretty quick work of checking off that box. We left on a vehicle by accident for about a week which didn't seem to effect it at all.
Randy from the U-P
Reviewed in the United States on January 31, 2025
The media could not be loaded.
twofouroh
Reviewed in the United States on January 18, 2025
This is really good for making sure the connector on my truck is right -before- I hook a trailer to it. It's so much easier to fix when nothing is hooked up. After testing the truck, I hook up the trailer,and if it isn't working, I know it's the trailer. I also like the turnable display so I can point it where my backup camera can see it.It's great!
Adad
Reviewed in the United States on December 28, 2024
The 7-Way Trailer Plug Tester is an essential tool for anyone who tows. It’s straightforward to use and highly effective at diagnosing wiring issues, making it a great addition to your towing toolkit.Pros:Effective Diagnosis: This tester works perfectly, helping me quickly identify a wiring problem in my truck’s 7-pin trailer harness.Red LED Indicators: The clear and bright LED lights provide instant feedback on circuit functionality, making troubleshooting fast and easy.Affordable: Given its utility, the price is a bargain. It’s a small investment that can save a lot of time and frustration.Must-Have for Towing: If you plan to tow regularly, this tool is indispensable for ensuring your trailer lights are working correctly.Cons:Short Length: The tester may be too short to comfortably use if the trailer harness socket is in a deeper or less accessible location. An extension might be needed in such cases.Conclusion:This trailer light tester is a simple, reliable, and affordable solution for diagnosing trailer socket circuit problems. This tool is a must-have to ensure safety and proper functionality. While its short length could pose challenges in some setups, it’s still a highly valuable and reliable product.
duckslayer
Reviewed in the United States on December 15, 2024
I tried this on my 2020 GMC 2500HD and all it would show was bright green LED on 12V and a faint flashing green LED for RT and LT at the same time. Hooked up the truck to my boat trailer and confirmed that all the trailer lights work just as they should. Looks like I got a bad one......