Instant Trailer Circuit Diagnoser

Instantly Diagnose Trailer Wiring Faults
A plug-and-play solution for quickly checking circuits on RVs, trucks, and trailers with 7-pin European standard connectors. No more guesswork.


Synchronized Dual-Side Testing with Clear LED Indicators
This tester connects directly between your towing vehicle and trailer, simultaneously checking the light circuits on both sides. The intuitive LED panel provides immediate, synchronized feedback for each of the 7 pins, clearly indicating any faults according to the ISO 1724 standard.

Simple Plug-and-Play Operation
Forget complex setups, wire cutting, or splicing. Simply plug the tester into the sockets, press the side button to test the trailer side, and observe the lights. Its straightforward design makes it easy for anyone to perform a pre-trip safety check in seconds.

Built Tough for Wide Compatibility
Engineered for broad application, this unit works with most 12V commercial vehicles, RVs, caravans, and trailers equipped with standard 7-pin round connectors. The housing is made from durable ABS plastic, and the contacts are premium copper for high conductivity and longevity.
Technical Specifications
| Connector Type | 7-Pin European Standard (Round) |
|---|---|
| Voltage | 12V DC |
| Standard | ISO 1724 |
| Housing Material | ABS Plastic |
| Contact Material | Copper |
| Display | 6-LED Indicator Panel |
| Power Source | Vehicle Battery (Car Side) / 9V Battery (Trailer Side - Not Included) |
Frequently Asked Questions